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[PATCH v4 00/24] OpenRISC patches for 4.11

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  [PATCH v4 00/24] OpenRISC patches for 4.11 Stafford Horne <shorne@gmail.com> - 2017-02-24 05:40 +0100
    [PATCH v4 23/24] openrisc: Export ioremap symbols used by modules Stafford Horne <shorne@gmail.com> - 2017-02-24 05:40 +0100
    [PATCH v4 13/24] openrisc: Initial support for the idle state Stafford Horne <shorne@gmail.com> - 2017-02-24 05:40 +0100
    [PATCH v4 18/24] scripts/checkstack.pl: Add openrisc support Stafford Horne <shorne@gmail.com> - 2017-02-24 05:40 +0100
      Re: [PATCH v4 18/24] scripts/checkstack.pl: Add openrisc support Tobias Klauser <tklauser@distanz.ch> - 2017-02-24 16:00 +0100
        Re: [PATCH v4 18/24] scripts/checkstack.pl: Add openrisc support Stafford Horne <shorne@gmail.com> - 2017-02-24 20:40 +0100
    [PATCH v4 22/24] arch/openrisc/lib/memcpy.c: use correct OR1200 option Stafford Horne <shorne@gmail.com> - 2017-02-24 05:40 +0100
      Re: [PATCH v4 22/24] arch/openrisc/lib/memcpy.c: use correct OR1200  option Jonas Bonn <jonas@southpole.se> - 2017-02-24 10:50 +0100
        Re: [PATCH v4 22/24] arch/openrisc/lib/memcpy.c: use correct OR1200  option Stafford Horne <shorne@gmail.com> - 2017-02-24 21:00 +0100
    [PATCH v4 08/24] openrisc: add cmpxchg and xchg implementations Stafford Horne <shorne@gmail.com> - 2017-02-24 05:40 +0100
    [PATCH v4 20/24] openrisc: entry: Fix delay slot detection Stafford Horne <shorne@gmail.com> - 2017-02-24 05:40 +0100
      Re: [PATCH v4 20/24] openrisc: entry: Fix delay slot detection Jonas Bonn <jonas@southpole.se> - 2017-02-24 11:00 +0100
        Re: [PATCH v4 20/24] openrisc: entry: Fix delay slot detection Stafford Horne <shorne@gmail.com> - 2017-02-24 21:20 +0100
    [PATCH v4 09/24] openrisc: add optimized atomic operations Stafford Horne <shorne@gmail.com> - 2017-02-24 05:40 +0100
    [PATCH v4 04/24] openrisc: head: use THREAD_SIZE instead of magic constant Stafford Horne <shorne@gmail.com> - 2017-02-24 05:40 +0100
    [PATCH v4 07/24] openrisc: add atomic bitops Stafford Horne <shorne@gmail.com> - 2017-02-24 05:40 +0100
      Re: [PATCH v4 07/24] openrisc: add atomic bitops Peter Zijlstra <peterz@infradead.org> - 2017-02-24 12:00 +0100
        Re: [PATCH v4 07/24] openrisc: add atomic bitops Stafford Horne <shorne@gmail.com> - 2017-02-24 20:30 +0100
    [PATCH v4 11/24] openrisc: remove unnecessary stddef.h include Stafford Horne <shorne@gmail.com> - 2017-02-24 05:40 +0100
    [PATCH v4 01/24] openrisc: use SPARSE_IRQ Stafford Horne <shorne@gmail.com> - 2017-02-24 05:40 +0100
    [PATCH v4 21/24] openrisc: head: Move init strings to rodata section Stafford Horne <shorne@gmail.com> - 2017-02-24 05:40 +0100
      Re: [PATCH v4 21/24] openrisc: head: Move init strings to rodata  section Jonas Bonn <jonas@southpole.se> - 2017-02-24 11:00 +0100
        Re: [PATCH v4 21/24] openrisc: head: Move init strings to rodata  section Stafford Horne <shorne@gmail.com> - 2017-02-24 21:20 +0100
    [PATCH v4 05/24] openrisc: head: refactor out tlb flush into it's own function Stafford Horne <shorne@gmail.com> - 2017-02-24 05:40 +0100
      Re: [PATCH v4 05/24] openrisc: head: refactor out tlb flush into it's  own function Jonas Bonn <jonas@southpole.se> - 2017-02-24 11:00 +0100
        Re: [PATCH v4 05/24] openrisc: head: refactor out tlb flush into  it's own function Stefan Kristiansson <stefan.kristiansson@saunalahti.fi> - 2017-02-24 12:10 +0100
          Re: [PATCH v4 05/24] openrisc: head: refactor out tlb flush into it's  own function Jonas Bonn <jonas@southpole.se> - 2017-02-24 13:50 +0100
            Re: [PATCH v4 05/24] openrisc: head: refactor out tlb flush into  it's own function Stefan Kristiansson <stefan.kristiansson@saunalahti.fi> - 2017-02-24 15:00 +0100
              Re: [PATCH v4 05/24] openrisc: head: refactor out tlb flush into  it's own function Stafford Horne <shorne@gmail.com> - 2017-02-24 20:30 +0100
    [PATCH v4 24/24] openrisc: head: Init r0 to 0 on start Stafford Horne <shorne@gmail.com> - 2017-02-24 05:40 +0100
      Re: [PATCH v4 24/24] openrisc: head: Init r0 to 0 on start Jonas Bonn <jonas@southpole.se> - 2017-02-24 11:10 +0100
        Re: [PATCH v4 24/24] openrisc: head: Init r0 to 0 on start Stafford Horne <shorne@gmail.com> - 2017-02-24 20:40 +0100
    [PATCH v4 17/24] MAINTAINERS: Add the openrisc official repository Stafford Horne <shorne@gmail.com> - 2017-02-24 05:40 +0100
    [PATCH v4 12/24] openrisc: Fix the bitmask for the unit present register Stafford Horne <shorne@gmail.com> - 2017-02-24 05:40 +0100
    [PATCH v4 06/24] openrisc: add l.lwa/l.swa emulation Stafford Horne <shorne@gmail.com> - 2017-02-24 05:40 +0100
      Re: [PATCH v4 06/24] openrisc: add l.lwa/l.swa emulation Jonas Bonn <jonas@southpole.se> - 2017-02-24 10:50 +0100
        Re: [PATCH v4 06/24] openrisc: add l.lwa/l.swa emulation Stafford Horne <shorne@gmail.com> - 2017-02-24 21:00 +0100
    [PATCH v4 10/24] openrisc: add futex_atomic_* implementations Stafford Horne <shorne@gmail.com> - 2017-02-24 05:40 +0100
    [PATCH v4 03/24] openrisc: tlb miss handler optimizations Stafford Horne <shorne@gmail.com> - 2017-02-24 05:40 +0100
    [PATCH v4 19/24] openrisc: entry: Whitespace and comment cleanups Stafford Horne <shorne@gmail.com> - 2017-02-24 05:40 +0100
      Re: [PATCH v4 19/24] openrisc: entry: Whitespace and comment cleanups Jonas Bonn <jonas@southpole.se> - 2017-02-24 10:50 +0100
        Re: [PATCH v4 19/24] openrisc: entry: Whitespace and comment cleanups Stafford Horne <shorne@gmail.com> - 2017-02-24 21:40 +0100
    [PATCH v4 15/24] openrisc: Add optimized memcpy routine Stafford Horne <shorne@gmail.com> - 2017-02-24 05:50 +0100
    [PATCH v4 16/24] openrisc: Add .gitignore Stafford Horne <shorne@gmail.com> - 2017-02-24 05:50 +0100
    [PATCH v4 14/24] openrisc: Add optimized memset Stafford Horne <shorne@gmail.com> - 2017-02-24 05:50 +0100

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#1587289 — [PATCH v4 21/24] openrisc: head: Move init strings to rodata section

The strings used during the head/init phase of openrisc bootup were
stored in the executable section of the binary.

This causes compilation to fail when using CONFIG_DEBUG_INFO with
error:
 Error: unaligned opcodes detected in executable segment

Also, this patch removes unused strings.

Signed-off-by: Stafford Horne <shorne@gmail.com>
---
 arch/openrisc/kernel/head.S | 12 +-----------
 1 file changed, 1 insertion(+), 11 deletions(-)

diff --git a/arch/openrisc/kernel/head.S b/arch/openrisc/kernel/head.S
index a22f1fc..573e131 100644
--- a/arch/openrisc/kernel/head.S
+++ b/arch/openrisc/kernel/head.S
@@ -1530,11 +1530,7 @@ ENTRY(_early_uart_init)
 	l.jr	r9
 	l.nop
 
-_string_copying_linux:
-	.string "\n\n\n\n\n\rCopying Linux... \0"
-
-_string_ok_booting:
-	.string "Ok, booting the kernel.\n\r\0"
+	.section .rodata
 
 _string_unhandled_exception:
 	.string "\n\rRunarunaround: Unhandled exception 0x\0"
@@ -1545,12 +1541,6 @@ _string_epc_prefix:
 _string_nl:
 	.string "\n\r\0"
 
-	.global	_string_esr_irq_bug
-_string_esr_irq_bug:
-	.string "\n\rESR external interrupt bug, for details look into entry.S\n\r\0"
-
-
-
 /* ========================================[ page aligned structures ]=== */
 
 /*
-- 
2.9.3

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#1587483 — Re: [PATCH v4 21/24] openrisc: head: Move init strings to rodata section

On 02/24/2017 05:32 AM, Stafford Horne wrote:
> The strings used during the head/init phase of openrisc bootup were
> stored in the executable section of the binary.
>
> This causes compilation to fail when using CONFIG_DEBUG_INFO with
> error:
>   Error: unaligned opcodes detected in executable segment
>
> Also, this patch removes unused strings.
This should be two patches:  one that removes unused strings and one 
that switches the data section.

Works like "Also" usually indicate that you are doing too much in your 
patch and you need to split it up.

/Jonas

>
> Signed-off-by: Stafford Horne <shorne@gmail.com>
> ---
>   arch/openrisc/kernel/head.S | 12 +-----------
>   1 file changed, 1 insertion(+), 11 deletions(-)
>
> diff --git a/arch/openrisc/kernel/head.S b/arch/openrisc/kernel/head.S
> index a22f1fc..573e131 100644
> --- a/arch/openrisc/kernel/head.S
> +++ b/arch/openrisc/kernel/head.S
> @@ -1530,11 +1530,7 @@ ENTRY(_early_uart_init)
>   	l.jr	r9
>   	l.nop
>   
> -_string_copying_linux:
> -	.string "\n\n\n\n\n\rCopying Linux... \0"
> -
> -_string_ok_booting:
> -	.string "Ok, booting the kernel.\n\r\0"
> +	.section .rodata
>   
>   _string_unhandled_exception:
>   	.string "\n\rRunarunaround: Unhandled exception 0x\0"
> @@ -1545,12 +1541,6 @@ _string_epc_prefix:
>   _string_nl:
>   	.string "\n\r\0"
>   
> -	.global	_string_esr_irq_bug
> -_string_esr_irq_bug:
> -	.string "\n\rESR external interrupt bug, for details look into entry.S\n\r\0"
> -
> -
> -
>   /* ========================================[ page aligned structures ]=== */
>   
>   /*

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#1587915 — Re: [PATCH v4 21/24] openrisc: head: Move init strings to rodata section

On Fri, Feb 24, 2017 at 10:28:46AM +0100, Jonas Bonn wrote:
> On 02/24/2017 05:32 AM, Stafford Horne wrote:
> > The strings used during the head/init phase of openrisc bootup were
> > stored in the executable section of the binary.
> > 
> > This causes compilation to fail when using CONFIG_DEBUG_INFO with
> > error:
> >   Error: unaligned opcodes detected in executable segment
> > 
> > Also, this patch removes unused strings.
> This should be two patches:  one that removes unused strings and one that
> switches the data section.
> 
> Works like "Also" usually indicate that you are doing too much in your patch
> and you need to split it up.

Hi Jonas,

Right, I'll split this one.  I was debating that due to the size. But
it would be right in this case.

Also, I use the word also a lot :)

-Stafford

> > 
> > Signed-off-by: Stafford Horne <shorne@gmail.com>
> > ---
> >   arch/openrisc/kernel/head.S | 12 +-----------
> >   1 file changed, 1 insertion(+), 11 deletions(-)
> > 
> > diff --git a/arch/openrisc/kernel/head.S b/arch/openrisc/kernel/head.S
> > index a22f1fc..573e131 100644
> > --- a/arch/openrisc/kernel/head.S
> > +++ b/arch/openrisc/kernel/head.S
> > @@ -1530,11 +1530,7 @@ ENTRY(_early_uart_init)
> >   	l.jr	r9
> >   	l.nop
> > -_string_copying_linux:
> > -	.string "\n\n\n\n\n\rCopying Linux... \0"
> > -
> > -_string_ok_booting:
> > -	.string "Ok, booting the kernel.\n\r\0"
> > +	.section .rodata
> >   _string_unhandled_exception:
> >   	.string "\n\rRunarunaround: Unhandled exception 0x\0"
> > @@ -1545,12 +1541,6 @@ _string_epc_prefix:
> >   _string_nl:
> >   	.string "\n\r\0"
> > -	.global	_string_esr_irq_bug
> > -_string_esr_irq_bug:
> > -	.string "\n\rESR external interrupt bug, for details look into entry.S\n\r\0"
> > -
> > -
> > -
> >   /* ========================================[ page aligned structures ]=== */
> >   /*
> 
> 

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#1587290 — [PATCH v4 05/24] openrisc: head: refactor out tlb flush into it's own function

From: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>

This brings it inline with the other setup oprations done like the cache
enables _ic_enable and _dc_enable.  Also, this is going to make it
easier to initialize additional cpu's when smp is introduced.

Signed-off-by: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
[shorne@gmail.com: Added commit body]
Signed-off-by: Stafford Horne <shorne@gmail.com>
---
 arch/openrisc/kernel/head.S | 38 ++++++++++++++++++++++----------------
 1 file changed, 22 insertions(+), 16 deletions(-)

diff --git a/arch/openrisc/kernel/head.S b/arch/openrisc/kernel/head.S
index 63ba2d9..a22f1fc 100644
--- a/arch/openrisc/kernel/head.S
+++ b/arch/openrisc/kernel/head.S
@@ -522,22 +522,8 @@ enable_dc:
 	 l.nop
 
 flush_tlb:
-	/*
-	 *  I N V A L I D A T E   T L B   e n t r i e s
-	 */
-	LOAD_SYMBOL_2_GPR(r5,SPR_DTLBMR_BASE(0))
-	LOAD_SYMBOL_2_GPR(r6,SPR_ITLBMR_BASE(0))
-	l.addi	r7,r0,128 /* Maximum number of sets */
-1:
-	l.mtspr	r5,r0,0x0
-	l.mtspr	r6,r0,0x0
-
-	l.addi	r5,r5,1
-	l.addi	r6,r6,1
-	l.sfeq	r7,r0
-	l.bnf	1b
-	 l.addi	r7,r7,-1
-
+	l.jal	_flush_tlb
+	 l.nop
 
 /* The MMU needs to be enabled before or32_early_setup is called */
 
@@ -629,6 +615,26 @@ jump_start_kernel:
 	l.jr    r30
 	 l.nop
 
+_flush_tlb:
+	/*
+	 *  I N V A L I D A T E   T L B   e n t r i e s
+	 */
+	LOAD_SYMBOL_2_GPR(r5,SPR_DTLBMR_BASE(0))
+	LOAD_SYMBOL_2_GPR(r6,SPR_ITLBMR_BASE(0))
+	l.addi	r7,r0,128 /* Maximum number of sets */
+1:
+	l.mtspr	r5,r0,0x0
+	l.mtspr	r6,r0,0x0
+
+	l.addi	r5,r5,1
+	l.addi	r6,r6,1
+	l.sfeq	r7,r0
+	l.bnf	1b
+	 l.addi	r7,r7,-1
+
+	l.jr	r9
+	 l.nop
+
 /* ========================================[ cache ]=== */
 
 	/* aligment here so we don't change memory offsets with
-- 
2.9.3

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#1587477 — Re: [PATCH v4 05/24] openrisc: head: refactor out tlb flush into it's own function

On 02/24/2017 05:32 AM, Stafford Horne wrote:
> From: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
>
> This brings it inline with the other setup oprations done like the cache
> enables _ic_enable and _dc_enable.  Also, this is going to make it
> easier to initialize additional cpu's when smp is introduced.

This patch confuses me.  The TLB flush is moved to a point after MMU's 
are enabled.  The TLB flush should happen before enabling the MMU, 
shouldn't it?

/Jonas

>
> Signed-off-by: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
> [shorne@gmail.com: Added commit body]
> Signed-off-by: Stafford Horne <shorne@gmail.com>
> ---
>   arch/openrisc/kernel/head.S | 38 ++++++++++++++++++++++----------------
>   1 file changed, 22 insertions(+), 16 deletions(-)
>
> diff --git a/arch/openrisc/kernel/head.S b/arch/openrisc/kernel/head.S
> index 63ba2d9..a22f1fc 100644
> --- a/arch/openrisc/kernel/head.S
> +++ b/arch/openrisc/kernel/head.S
> @@ -522,22 +522,8 @@ enable_dc:
>   	 l.nop
>   
>   flush_tlb:
> -	/*
> -	 *  I N V A L I D A T E   T L B   e n t r i e s
> -	 */
> -	LOAD_SYMBOL_2_GPR(r5,SPR_DTLBMR_BASE(0))
> -	LOAD_SYMBOL_2_GPR(r6,SPR_ITLBMR_BASE(0))
> -	l.addi	r7,r0,128 /* Maximum number of sets */
> -1:
> -	l.mtspr	r5,r0,0x0
> -	l.mtspr	r6,r0,0x0
> -
> -	l.addi	r5,r5,1
> -	l.addi	r6,r6,1
> -	l.sfeq	r7,r0
> -	l.bnf	1b
> -	 l.addi	r7,r7,-1
> -
> +	l.jal	_flush_tlb
> +	 l.nop
>   
>   /* The MMU needs to be enabled before or32_early_setup is called */
>   
> @@ -629,6 +615,26 @@ jump_start_kernel:
>   	l.jr    r30
>   	 l.nop
>   
> +_flush_tlb:
> +	/*
> +	 *  I N V A L I D A T E   T L B   e n t r i e s
> +	 */
> +	LOAD_SYMBOL_2_GPR(r5,SPR_DTLBMR_BASE(0))
> +	LOAD_SYMBOL_2_GPR(r6,SPR_ITLBMR_BASE(0))
> +	l.addi	r7,r0,128 /* Maximum number of sets */
> +1:
> +	l.mtspr	r5,r0,0x0
> +	l.mtspr	r6,r0,0x0
> +
> +	l.addi	r5,r5,1
> +	l.addi	r6,r6,1
> +	l.sfeq	r7,r0
> +	l.bnf	1b
> +	 l.addi	r7,r7,-1
> +
> +	l.jr	r9
> +	 l.nop
> +
>   /* ========================================[ cache ]=== */
>   
>   	/* aligment here so we don't change memory offsets with

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#1587520 — Re: [PATCH v4 05/24] openrisc: head: refactor out tlb flush into it's own function

eOn Fri, Feb 24, 2017 at 10:57:19AM +0100, Jonas Bonn wrote:
> On 02/24/2017 05:32 AM, Stafford Horne wrote:
> >From: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
> >
> >This brings it inline with the other setup oprations done like the cache
> >enables _ic_enable and _dc_enable.  Also, this is going to make it
> >easier to initialize additional cpu's when smp is introduced.
> 
> This patch confuses me.  The TLB flush is moved to a point after MMU's are
> enabled.  The TLB flush should happen before enabling the MMU, shouldn't it?
> 

It still happens before the MMUs are enabled, the patch only refactors the code
out into a function that is called from the place where it was open coded
before.

Stefan

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#1587569 — Re: [PATCH v4 05/24] openrisc: head: refactor out tlb flush into it's own function

On 02/24/2017 11:54 AM, Stefan Kristiansson wrote:
> eOn Fri, Feb 24, 2017 at 10:57:19AM +0100, Jonas Bonn wrote:
>> On 02/24/2017 05:32 AM, Stafford Horne wrote:
>>> From: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
>>>
>>> This brings it inline with the other setup oprations done like the cache
>>> enables _ic_enable and _dc_enable.  Also, this is going to make it
>>> easier to initialize additional cpu's when smp is introduced.
>> This patch confuses me.  The TLB flush is moved to a point after MMU's are
>> enabled.  The TLB flush should happen before enabling the MMU, shouldn't it?
>>
> It still happens before the MMUs are enabled, the patch only refactors the code
> out into a function that is called from the place where it was open coded
> before.

Right.  What's the point of moving it then?

/Jonas

>
> Stefan

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#1587679 — Re: [PATCH v4 05/24] openrisc: head: refactor out tlb flush into it's own function

On Fri, Feb 24, 2017 at 01:48:10PM +0100, Jonas Bonn wrote:
> On 02/24/2017 11:54 AM, Stefan Kristiansson wrote:
> >eOn Fri, Feb 24, 2017 at 10:57:19AM +0100, Jonas Bonn wrote:
> >>On 02/24/2017 05:32 AM, Stafford Horne wrote:
> >>>From: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
> >>>
> >>>This brings it inline with the other setup oprations done like the cache
> >>>enables _ic_enable and _dc_enable.  Also, this is going to make it
> >>>easier to initialize additional cpu's when smp is introduced.
> >>This patch confuses me.  The TLB flush is moved to a point after MMU's are
> >>enabled.  The TLB flush should happen before enabling the MMU, shouldn't it?
> >>
> >It still happens before the MMUs are enabled, the patch only refactors the code
> >out into a function that is called from the place where it was open coded
> >before.
> 
> Right.  What's the point of moving it then?
> 

As the commit message mentions, it's a preparation patch for initialisation
of secondary cpus, which also will call this function.

Perhaps this patch should be bundled with those patches.

Stefan

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#1587878 — Re: [PATCH v4 05/24] openrisc: head: refactor out tlb flush into it's own function

On Fri, Feb 24, 2017 at 03:54:02PM +0200, Stefan Kristiansson wrote:
> On Fri, Feb 24, 2017 at 01:48:10PM +0100, Jonas Bonn wrote:
> > On 02/24/2017 11:54 AM, Stefan Kristiansson wrote:
> > >eOn Fri, Feb 24, 2017 at 10:57:19AM +0100, Jonas Bonn wrote:
> > >>On 02/24/2017 05:32 AM, Stafford Horne wrote:
> > >>>From: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
> > >>>
> > >>>This brings it inline with the other setup oprations done like the cache
> > >>>enables _ic_enable and _dc_enable.  Also, this is going to make it
> > >>>easier to initialize additional cpu's when smp is introduced.
> > >>This patch confuses me.  The TLB flush is moved to a point after MMU's are
> > >>enabled.  The TLB flush should happen before enabling the MMU, shouldn't it?
> > >>
> > >It still happens before the MMUs are enabled, the patch only refactors the code
> > >out into a function that is called from the place where it was open coded
> > >before.
> > 
> > Right.  What's the point of moving it then?
> > 
> 
> As the commit message mentions, it's a preparation patch for initialisation
> of secondary cpus, which also will call this function.
> 
> Perhaps this patch should be bundled with those patches.
> 

Thanks for replying on this patch, I think keeping this patch here is
ok.  Since part of the theme of this series is preparing for SMP (which
will be another big series) I think its ok have any non SMP specific
work into here.  Its going to make my life a bit easier going forward.

Also, as this is good refactor to get it structurally in sync with other
initializations I think its not completely out of place.

-Stafford

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#1587291 — [PATCH v4 24/24] openrisc: head: Init r0 to 0 on start

Originally openrisc spec 0 specified that r0 would be wired to ground.
This is no longer the case.  r0 is not guaranteed to be 0 at init, so we
need to initialize it to 0 before using it.

Also, if we are clearing r0 we cant use r0 to clear itself. Change the
the CLEAR_GPR macro to use movhi for clearing.

Signed-off-by: Stafford Horne <shorne@gmail.com>
---
 arch/openrisc/kernel/head.S | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/arch/openrisc/kernel/head.S b/arch/openrisc/kernel/head.S
index 573e131..e8a1784 100644
--- a/arch/openrisc/kernel/head.S
+++ b/arch/openrisc/kernel/head.S
@@ -35,7 +35,7 @@
 	l.add	rd,rd,rs
 
 #define CLEAR_GPR(gpr)				\
-	l.or    gpr,r0,r0
+	l.movhi	gpr,0x0
 
 #define LOAD_SYMBOL_2_GPR(gpr,symbol)		\
 	l.movhi gpr,hi(symbol)			;\
@@ -443,6 +443,9 @@ _dispatch_do_ipage_fault:
 	__HEAD
 	.global _start
 _start:
+	/* Init r0 to zero as per spec */
+	CLEAR_GPR(r0)
+
 	/* save kernel parameters */
 	l.or	r25,r0,r3	/* pointer to fdt */
 
-- 
2.9.3

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#1587485 — Re: [PATCH v4 24/24] openrisc: head: Init r0 to 0 on start

On 02/24/2017 05:32 AM, Stafford Horne wrote:
> Originally openrisc spec 0 specified that r0 would be wired to ground.
> This is no longer the case.  r0 is not guaranteed to be 0 at init, so we
> need to initialize it to 0 before using it.
>
> Also, if we are clearing r0 we cant use r0 to clear itself. Change the
> the CLEAR_GPR macro to use movhi for clearing.

Use the Reported-by: tag here since you are taking the time to mention 
him in the summary mail.

Reported-by:  Jakob...
> Signed-off-by: Stafford Horne <shorne@gmail.com>
> ---
>   arch/openrisc/kernel/head.S | 5 ++++-
>   1 file changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/arch/openrisc/kernel/head.S b/arch/openrisc/kernel/head.S
> index 573e131..e8a1784 100644
> --- a/arch/openrisc/kernel/head.S
> +++ b/arch/openrisc/kernel/head.S
> @@ -35,7 +35,7 @@
>   	l.add	rd,rd,rs
>   
>   #define CLEAR_GPR(gpr)				\
> -	l.or    gpr,r0,r0
> +	l.movhi	gpr,0x0
>   
>   #define LOAD_SYMBOL_2_GPR(gpr,symbol)		\
>   	l.movhi gpr,hi(symbol)			;\
> @@ -443,6 +443,9 @@ _dispatch_do_ipage_fault:
>   	__HEAD
>   	.global _start
>   _start:
> +	/* Init r0 to zero as per spec */
> +	CLEAR_GPR(r0)
> +
>   	/* save kernel parameters */
>   	l.or	r25,r0,r3	/* pointer to fdt */
>   

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#1587887 — Re: [PATCH v4 24/24] openrisc: head: Init r0 to 0 on start

On Fri, Feb 24, 2017 at 10:21:50AM +0100, Jonas Bonn wrote:
> On 02/24/2017 05:32 AM, Stafford Horne wrote:
> > Originally openrisc spec 0 specified that r0 would be wired to ground.
> > This is no longer the case.  r0 is not guaranteed to be 0 at init, so we
> > need to initialize it to 0 before using it.
> > 
> > Also, if we are clearing r0 we cant use r0 to clear itself. Change the
> > the CLEAR_GPR macro to use movhi for clearing.
> 
> Use the Reported-by: tag here since you are taking the time to mention him
> in the summary mail.

Right, added.

Thanks.

> Reported-by:  Jakob...
> > Signed-off-by: Stafford Horne <shorne@gmail.com>
> > ---
> >   arch/openrisc/kernel/head.S | 5 ++++-
> >   1 file changed, 4 insertions(+), 1 deletion(-)
> > 
> > diff --git a/arch/openrisc/kernel/head.S b/arch/openrisc/kernel/head.S
> > index 573e131..e8a1784 100644
> > --- a/arch/openrisc/kernel/head.S
> > +++ b/arch/openrisc/kernel/head.S
> > @@ -35,7 +35,7 @@
> >   	l.add	rd,rd,rs
> >   #define CLEAR_GPR(gpr)				\
> > -	l.or    gpr,r0,r0
> > +	l.movhi	gpr,0x0
> >   #define LOAD_SYMBOL_2_GPR(gpr,symbol)		\
> >   	l.movhi gpr,hi(symbol)			;\
> > @@ -443,6 +443,9 @@ _dispatch_do_ipage_fault:
> >   	__HEAD
> >   	.global _start
> >   _start:
> > +	/* Init r0 to zero as per spec */
> > +	CLEAR_GPR(r0)
> > +
> >   	/* save kernel parameters */
> >   	l.or	r25,r0,r3	/* pointer to fdt */
> 
> 

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#1587292 — [PATCH v4 17/24] MAINTAINERS: Add the openrisc official repository

The openrisc official repository and patch work happens currently on
github. Add the repo for reference.

Signed-off-by: Stafford Horne <shorne@gmail.com>
---
 MAINTAINERS | 1 +
 1 file changed, 1 insertion(+)

diff --git a/MAINTAINERS b/MAINTAINERS
index 187b961..57809d6 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -9187,6 +9187,7 @@ OPENRISC ARCHITECTURE
 M:	Jonas Bonn <jonas@southpole.se>
 M:	Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
 M:	Stafford Horne <shorne@gmail.com>
+T:	git git://github.com/openrisc/linux.git
 L:	openrisc@lists.librecores.org
 W:	http://openrisc.io
 S:	Maintained
-- 
2.9.3

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#1587294 — [PATCH v4 12/24] openrisc: Fix the bitmask for the unit present register

From: Sebastian Macke <sebastian@macke.de>

The bits were swapped, as per spec and processor implementation the
power management present bit is 9 and PIC bit is 8. This patch brings
the definitions into spec.

Signed-off-by: Sebastian Macke <sebastian@macke.de>
[shorne@gmail.com: Added commit body]
Signed-off-by: Stafford Horne <shorne@gmail.com>
---
 arch/openrisc/include/asm/spr_defs.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/openrisc/include/asm/spr_defs.h b/arch/openrisc/include/asm/spr_defs.h
index 5dbc668..367dac7 100644
--- a/arch/openrisc/include/asm/spr_defs.h
+++ b/arch/openrisc/include/asm/spr_defs.h
@@ -152,8 +152,8 @@
 #define SPR_UPR_MP	   0x00000020  /* MAC present */
 #define SPR_UPR_DUP	   0x00000040  /* Debug unit present */
 #define SPR_UPR_PCUP	   0x00000080  /* Performance counters unit present */
-#define SPR_UPR_PMP	   0x00000100  /* Power management present */
-#define SPR_UPR_PICP	   0x00000200  /* PIC present */
+#define SPR_UPR_PICP	   0x00000100  /* PIC present */
+#define SPR_UPR_PMP	   0x00000200  /* Power management present */
 #define SPR_UPR_TTP	   0x00000400  /* Tick timer present */
 #define SPR_UPR_RES	   0x00fe0000  /* Reserved */
 #define SPR_UPR_CUP	   0xff000000  /* Context units present */
-- 
2.9.3

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#1587295 — [PATCH v4 06/24] openrisc: add l.lwa/l.swa emulation

From: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>

This adds an emulation layer for implementations
that lack the l.lwa and l.swa instructions.
It handles these instructions both in kernel space and
user space.

Signed-off-by: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
[shorne@gmail.com: Added delay slot pc adjust logic]
Signed-off-by: Stafford Horne <shorne@gmail.com>
---
 arch/openrisc/kernel/entry.S   |  22 ++++-
 arch/openrisc/kernel/process.c |   3 +
 arch/openrisc/kernel/traps.c   | 183 +++++++++++++++++++++++++++++++++++++++++
 3 files changed, 206 insertions(+), 2 deletions(-)

diff --git a/arch/openrisc/kernel/entry.S b/arch/openrisc/kernel/entry.S
index aac0bde..ba1a361 100644
--- a/arch/openrisc/kernel/entry.S
+++ b/arch/openrisc/kernel/entry.S
@@ -173,6 +173,11 @@ handler:							;\
 	l.j	_ret_from_exception				;\
 	 l.nop
 
+/* clobbers 'reg' */
+#define CLEAR_LWA_FLAG(reg)		\
+	l.movhi	reg,hi(lwa_flag)	;\
+	l.ori	reg,reg,lo(lwa_flag)	;\
+	l.sw	0(reg),r0
 /*
  * NOTE: one should never assume that SPR_EPC, SPR_ESR, SPR_EEAR
  *       contain the same values as when exception we're handling
@@ -193,6 +198,7 @@ EXCEPTION_ENTRY(_tng_kernel_start)
 /* ---[ 0x200: BUS exception ]------------------------------------------- */
 
 EXCEPTION_ENTRY(_bus_fault_handler)
+	CLEAR_LWA_FLAG(r3)
 	/* r4: EA of fault (set by EXCEPTION_HANDLE) */
 	l.jal   do_bus_fault
 	 l.addi  r3,r1,0 /* pt_regs */
@@ -202,11 +208,13 @@ EXCEPTION_ENTRY(_bus_fault_handler)
 
 /* ---[ 0x300: Data Page Fault exception ]------------------------------- */
 EXCEPTION_ENTRY(_dtlb_miss_page_fault_handler)
+	CLEAR_LWA_FLAG(r3)
 	l.and	r5,r5,r0
 	l.j	1f
 	 l.nop
 
 EXCEPTION_ENTRY(_data_page_fault_handler)
+	CLEAR_LWA_FLAG(r3)
 	/* set up parameters for do_page_fault */
 	l.ori	r5,r0,0x300		   // exception vector
 1:
@@ -282,11 +290,13 @@ EXCEPTION_ENTRY(_data_page_fault_handler)
 
 /* ---[ 0x400: Insn Page Fault exception ]------------------------------- */
 EXCEPTION_ENTRY(_itlb_miss_page_fault_handler)
+	CLEAR_LWA_FLAG(r3)
 	l.and	r5,r5,r0
 	l.j	1f
 	 l.nop
 
 EXCEPTION_ENTRY(_insn_page_fault_handler)
+	CLEAR_LWA_FLAG(r3)
 	/* set up parameters for do_page_fault */
 	l.ori	r5,r0,0x400		   // exception vector
 1:
@@ -304,6 +314,7 @@ EXCEPTION_ENTRY(_insn_page_fault_handler)
 /* ---[ 0x500: Timer exception ]----------------------------------------- */
 
 EXCEPTION_ENTRY(_timer_handler)
+	CLEAR_LWA_FLAG(r3)
 	l.jal	timer_interrupt
 	 l.addi r3,r1,0 /* pt_regs */
 
@@ -313,6 +324,7 @@ EXCEPTION_ENTRY(_timer_handler)
 /* ---[ 0x600: Aligment exception ]-------------------------------------- */
 
 EXCEPTION_ENTRY(_alignment_handler)
+	CLEAR_LWA_FLAG(r3)
 	/* r4: EA of fault (set by EXCEPTION_HANDLE) */
 	l.jal   do_unaligned_access
 	 l.addi  r3,r1,0 /* pt_regs */
@@ -509,6 +521,7 @@ EXCEPTION_ENTRY(_external_irq_handler)
 //	l.sw	PT_SR(r1),r4
 1:
 #endif
+	CLEAR_LWA_FLAG(r3)
 	l.addi	r3,r1,0
 	l.movhi	r8,hi(do_IRQ)
 	l.ori	r8,r8,lo(do_IRQ)
@@ -556,8 +569,12 @@ ENTRY(_sys_call_handler)
 	 * they should be clobbered, otherwise
 	 */
 	l.sw    PT_GPR3(r1),r3
-	/* r4 already saved */
-	/* r4 holds the EEAR address of the fault, load the original r4 */
+	/*
+	 * r4 already saved
+	 * r4 holds the EEAR address of the fault, use it as screatch reg and
+	 * then load the original r4
+	 */
+	CLEAR_LWA_FLAG(r4)
 	l.lwz	r4,PT_GPR4(r1)
 	l.sw    PT_GPR5(r1),r5
 	l.sw    PT_GPR6(r1),r6
@@ -776,6 +793,7 @@ UNHANDLED_EXCEPTION(_vector_0xd00,0xd00)
 /* ---[ 0xe00: Trap exception ]------------------------------------------ */
 
 EXCEPTION_ENTRY(_trap_handler)
+	CLEAR_LWA_FLAG(r3)
 	/* r4: EA of fault (set by EXCEPTION_HANDLE) */
 	l.jal   do_trap
 	 l.addi  r3,r1,0 /* pt_regs */
diff --git a/arch/openrisc/kernel/process.c b/arch/openrisc/kernel/process.c
index d7990df..c49350b 100644
--- a/arch/openrisc/kernel/process.c
+++ b/arch/openrisc/kernel/process.c
@@ -226,6 +226,7 @@ int dump_fpu(struct pt_regs *regs, elf_fpregset_t * fpu)
 
 extern struct thread_info *_switch(struct thread_info *old_ti,
 				   struct thread_info *new_ti);
+extern int lwa_flag;
 
 struct task_struct *__switch_to(struct task_struct *old,
 				struct task_struct *new)
@@ -243,6 +244,8 @@ struct task_struct *__switch_to(struct task_struct *old,
 	new_ti = new->stack;
 	old_ti = old->stack;
 
+	lwa_flag = 0;
+
 	current_thread_info_set[smp_processor_id()] = new_ti;
 	last = (_switch(old_ti, new_ti))->task;
 
diff --git a/arch/openrisc/kernel/traps.c b/arch/openrisc/kernel/traps.c
index a4574cb..7907b6c 100644
--- a/arch/openrisc/kernel/traps.c
+++ b/arch/openrisc/kernel/traps.c
@@ -40,6 +40,8 @@
 extern char _etext, _stext;
 
 int kstack_depth_to_print = 0x180;
+int lwa_flag;
+unsigned long __user *lwa_addr;
 
 static inline int valid_stack_ptr(struct thread_info *tinfo, void *p)
 {
@@ -334,10 +336,191 @@ asmlinkage void do_bus_fault(struct pt_regs *regs, unsigned long address)
 	}
 }
 
+static inline int in_delay_slot(struct pt_regs *regs)
+{
+#ifdef CONFIG_OPENRISC_NO_SPR_SR_DSX
+	/* No delay slot flag, do the old way */
+	unsigned int op, insn;
+
+	insn = *((unsigned int *)regs->pc);
+	op = insn >> 26;
+	switch (op) {
+	case 0x00: /* l.j */
+	case 0x01: /* l.jal */
+	case 0x03: /* l.bnf */
+	case 0x04: /* l.bf */
+	case 0x11: /* l.jr */
+	case 0x12: /* l.jalr */
+		return 1;
+	default:
+		return 0;
+	}
+#else
+	return regs->sr & SPR_SR_DSX;
+#endif
+}
+
+static inline void adjust_pc(struct pt_regs *regs, unsigned long address)
+{
+	int displacement;
+	unsigned int rb, op, jmp;
+
+	if (unlikely(in_delay_slot(regs))) {
+		/* In delay slot, instruction at pc is a branch, simulate it */
+		jmp = *((unsigned int *)regs->pc);
+
+		displacement = sign_extend32(((jmp) & 0x3ffffff) << 2, 27);
+		rb = (jmp & 0x0000ffff) >> 11;
+		op = jmp >> 26;
+
+		switch (op) {
+		case 0x00: /* l.j */
+			regs->pc += displacement;
+			return;
+		case 0x01: /* l.jal */
+			regs->pc += displacement;
+			regs->gpr[9] = regs->pc + 8;
+			return;
+		case 0x03: /* l.bnf */
+			if (regs->sr & SPR_SR_F)
+				regs->pc += 8;
+			else
+				regs->pc += displacement;
+			return;
+		case 0x04: /* l.bf */
+			if (regs->sr & SPR_SR_F)
+				regs->pc += displacement;
+			else
+				regs->pc += 8;
+			return;
+		case 0x11: /* l.jr */
+			regs->pc = regs->gpr[rb];
+			return;
+		case 0x12: /* l.jalr */
+			regs->pc = regs->gpr[rb];
+			regs->gpr[9] = regs->pc + 8;
+			return;
+		default:
+			break;
+		}
+	} else {
+		regs->pc += 4;
+	}
+}
+
+static inline void simulate_lwa(struct pt_regs *regs, unsigned long address,
+				unsigned int insn)
+{
+	unsigned int ra, rd;
+	unsigned long value;
+	unsigned long orig_pc;
+	long imm;
+
+	const struct exception_table_entry *entry;
+
+	orig_pc = regs->pc;
+	adjust_pc(regs, address);
+
+	ra = (insn >> 16) & 0x1f;
+	rd = (insn >> 21) & 0x1f;
+	imm = (short)insn;
+	lwa_addr = (unsigned long __user *)(regs->gpr[ra] + imm);
+
+	if ((unsigned long)lwa_addr & 0x3) {
+		do_unaligned_access(regs, address);
+		return;
+	}
+
+	if (get_user(value, lwa_addr)) {
+		if (user_mode(regs)) {
+			force_sig(SIGSEGV, current);
+			return;
+		}
+
+		if ((entry = search_exception_tables(orig_pc))) {
+			regs->pc = entry->fixup;
+			return;
+		}
+
+		/* kernel access in kernel space, load it directly */
+		value = *((unsigned long *)lwa_addr);
+	}
+
+	lwa_flag = 1;
+	regs->gpr[rd] = value;
+}
+
+static inline void simulate_swa(struct pt_regs *regs, unsigned long address,
+				unsigned int insn)
+{
+	unsigned long __user *vaddr;
+	unsigned long orig_pc;
+	unsigned int ra, rb;
+	long imm;
+
+	const struct exception_table_entry *entry;
+
+	orig_pc = regs->pc;
+	adjust_pc(regs, address);
+
+	ra = (insn >> 16) & 0x1f;
+	rb = (insn >> 11) & 0x1f;
+	imm = (short)(((insn & 0x2200000) >> 10) | (insn & 0x7ff));
+	vaddr = (unsigned long __user *)(regs->gpr[ra] + imm);
+
+	if (!lwa_flag || vaddr != lwa_addr) {
+		regs->sr &= ~SPR_SR_F;
+		return;
+	}
+
+	if ((unsigned long)vaddr & 0x3) {
+		do_unaligned_access(regs, address);
+		return;
+	}
+
+	if (put_user(regs->gpr[rb], vaddr)) {
+		if (user_mode(regs)) {
+			force_sig(SIGSEGV, current);
+			return;
+		}
+
+		if ((entry = search_exception_tables(orig_pc))) {
+			regs->pc = entry->fixup;
+			return;
+		}
+
+		/* kernel access in kernel space, store it directly */
+		*((unsigned long *)vaddr) = regs->gpr[rb];
+	}
+
+	lwa_flag = 0;
+	regs->sr |= SPR_SR_F;
+}
+
+#define INSN_LWA	0x1b
+#define INSN_SWA	0x33
+
 asmlinkage void do_illegal_instruction(struct pt_regs *regs,
 				       unsigned long address)
 {
 	siginfo_t info;
+	unsigned int op;
+	unsigned int insn = *((unsigned int *)address);
+
+	op = insn >> 26;
+
+	switch (op) {
+	case INSN_LWA:
+		simulate_lwa(regs, address, insn);
+		return;
+
+	case INSN_SWA:
+		simulate_swa(regs, address, insn);
+		return;
+
+	default:
+		break;
+	}
 
 	if (user_mode(regs)) {
 		/* Send a SIGILL */
-- 
2.9.3

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#1587475 — Re: [PATCH v4 06/24] openrisc: add l.lwa/l.swa emulation

On 02/24/2017 05:32 AM, Stafford Horne wrote:
> From: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
>
> This adds an emulation layer for implementations
> that lack the l.lwa and l.swa instructions.
> It handles these instructions both in kernel space and
> user space.
>
> Signed-off-by: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
> [shorne@gmail.com: Added delay slot pc adjust logic]
> Signed-off-by: Stafford Horne <shorne@gmail.com>
What happened here?  A bit of junk has slunk in among your Sign-offs!

/Jonas

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#1587902 — Re: [PATCH v4 06/24] openrisc: add l.lwa/l.swa emulation

On Fri, Feb 24, 2017 at 10:27:37AM +0100, Jonas Bonn wrote:
> On 02/24/2017 05:32 AM, Stafford Horne wrote:
> > From: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
> > 
> > This adds an emulation layer for implementations
> > that lack the l.lwa and l.swa instructions.
> > It handles these instructions both in kernel space and
> > user space.
> > 
> > Signed-off-by: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
> > [shorne@gmail.com: Added delay slot pc adjust logic]
> > Signed-off-by: Stafford Horne <shorne@gmail.com>
> What happened here?  A bit of junk has slunk in among your Sign-offs!

Hi Jonas,

I think this is standard notation for noting that the maintainer updated
the original patch.

In Documentions/process/submitting-patches.rst around line 480. Maybe
this is not a slight modification, but I didn't want split or take full
credit.

-Stafford

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#1587296 — [PATCH v4 10/24] openrisc: add futex_atomic_* implementations

From: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>

Support for the futex_atomic_* operations by using the
load-link/store-conditional l.lwa/l.swa instructions.
Most openrisc cores provide these instructions now if not available,
emulation is provided.

Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
[shorne@gmail.com: remove OPENRISC_HAVE_INST_LWA_SWA config suggesed by
Alan Cox https://lkml.org/lkml/2014/7/23/666]
Signed-off-by: Stafford Horne <shorne@gmail.com>
---
 arch/openrisc/include/asm/Kbuild  |   1 -
 arch/openrisc/include/asm/futex.h | 135 ++++++++++++++++++++++++++++++++++++++
 2 files changed, 135 insertions(+), 1 deletion(-)
 create mode 100644 arch/openrisc/include/asm/futex.h

diff --git a/arch/openrisc/include/asm/Kbuild b/arch/openrisc/include/asm/Kbuild
index 1cedd63..a669c14 100644
--- a/arch/openrisc/include/asm/Kbuild
+++ b/arch/openrisc/include/asm/Kbuild
@@ -20,7 +20,6 @@ generic-y += exec.h
 generic-y += fb.h
 generic-y += fcntl.h
 generic-y += ftrace.h
-generic-y += futex.h
 generic-y += hardirq.h
 generic-y += hw_irq.h
 generic-y += ioctl.h
diff --git a/arch/openrisc/include/asm/futex.h b/arch/openrisc/include/asm/futex.h
new file mode 100644
index 0000000..7780873
--- /dev/null
+++ b/arch/openrisc/include/asm/futex.h
@@ -0,0 +1,135 @@
+#ifndef __ASM_OPENRISC_FUTEX_H
+#define __ASM_OPENRISC_FUTEX_H
+
+#ifdef __KERNEL__
+
+#include <linux/futex.h>
+#include <linux/uaccess.h>
+#include <asm/errno.h>
+
+#define __futex_atomic_op(insn, ret, oldval, uaddr, oparg) \
+({								\
+	__asm__ __volatile__ (					\
+		"1:	l.lwa	%0, %2			\n"	\
+			insn				"\n"	\
+		"2:	l.swa	%2, %1			\n"	\
+		"	l.bnf	1b			\n"	\
+		"	 l.ori	%1, r0, 0		\n"	\
+		"3:					\n"	\
+		".section .fixup,\"ax\"			\n"	\
+		"4:	l.j	3b			\n"	\
+		"	 l.addi	%1, r0, %3		\n"	\
+		".previous				\n"	\
+		".section __ex_table,\"a\"		\n"	\
+		".word	1b,4b,2b,4b			\n"	\
+		".previous				\n"	\
+		: "=&r" (oldval), "=&r" (ret), "+m" (*uaddr)	\
+		: "i" (-EFAULT), "r" (oparg)			\
+		: "cc", "memory"				\
+		);						\
+})
+
+static inline int
+futex_atomic_op_inuser(int encoded_op, u32 __user *uaddr)
+{
+	int op = (encoded_op >> 28) & 7;
+	int cmp = (encoded_op >> 24) & 15;
+	int oparg = (encoded_op << 8) >> 20;
+	int cmparg = (encoded_op << 20) >> 20;
+	int oldval = 0, ret;
+
+	if (encoded_op & (FUTEX_OP_OPARG_SHIFT << 28))
+		oparg = 1 << oparg;
+
+	if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32)))
+		return -EFAULT;
+
+	pagefault_disable();
+
+	switch (op) {
+	case FUTEX_OP_SET:
+		__futex_atomic_op("l.or %1,%4,%4", ret, oldval, uaddr, oparg);
+		break;
+	case FUTEX_OP_ADD:
+		__futex_atomic_op("l.add %1,%0,%4", ret, oldval, uaddr, oparg);
+		break;
+	case FUTEX_OP_OR:
+		__futex_atomic_op("l.or %1,%0,%4", ret, oldval, uaddr, oparg);
+		break;
+	case FUTEX_OP_ANDN:
+		__futex_atomic_op("l.and %1,%0,%4", ret, oldval, uaddr, ~oparg);
+		break;
+	case FUTEX_OP_XOR:
+		__futex_atomic_op("l.xor %1,%0,%4", ret, oldval, uaddr, oparg);
+		break;
+	default:
+		ret = -ENOSYS;
+	}
+
+	pagefault_enable();
+
+	if (!ret) {
+		switch (cmp) {
+		case FUTEX_OP_CMP_EQ:
+			ret = (oldval == cmparg);
+			break;
+		case FUTEX_OP_CMP_NE:
+			ret = (oldval != cmparg);
+			break;
+		case FUTEX_OP_CMP_LT:
+			ret = (oldval < cmparg);
+			break;
+		case FUTEX_OP_CMP_GE:
+			ret = (oldval >= cmparg);
+			break;
+		case FUTEX_OP_CMP_LE:
+			ret = (oldval <= cmparg);
+			break;
+		case FUTEX_OP_CMP_GT:
+			ret = (oldval > cmparg);
+			break;
+		default:
+			ret = -ENOSYS;
+		}
+	}
+	return ret;
+}
+
+static inline int
+futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
+			      u32 oldval, u32 newval)
+{
+	int ret = 0;
+	u32 prev;
+
+	if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32)))
+		return -EFAULT;
+
+	__asm__ __volatile__ (				\
+		"1:	l.lwa	%1, %2		\n"	\
+		"	l.sfeq	%1, %3		\n"	\
+		"	l.bnf	3f		\n"	\
+		"	 l.nop			\n"	\
+		"2:	l.swa	%2, %4		\n"	\
+		"	l.bnf	1b		\n"	\
+		"	 l.nop			\n"	\
+		"3:				\n"	\
+		".section .fixup,\"ax\"		\n"	\
+		"4:	l.j	3b		\n"	\
+		"	 l.addi	%0, r0, %5	\n"	\
+		".previous			\n"	\
+		".section __ex_table,\"a\"	\n"	\
+		".word	1b,4b,2b,4b		\n"	\
+		".previous			\n"	\
+		: "+r" (ret), "=&r" (prev), "+m" (*uaddr) \
+		: "r" (oldval), "r" (newval), "i" (-EFAULT) \
+		: "cc",	"memory"			\
+		);
+
+	*uval = prev;
+	return ret;
+}
+
+#endif /* __KERNEL__ */
+
+#endif /* __ASM_OPENRISC_FUTEX_H */
-- 
2.9.3

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#1587297 — [PATCH v4 03/24] openrisc: tlb miss handler optimizations

From: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>

By slightly reorganizing the code, the number of registers
used in the tlb miss handlers can be reduced by two,
thus removing the need to save them to memory.

Also, some dead and commented out code is removed.

No functional change.

Signed-off-by: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
Signed-off-by: Jonas Bonn <jonas@southpole.se>
Signed-off-by: Stafford Horne <shorne@gmail.com>
---
 arch/openrisc/kernel/head.S | 141 +++++++++++++++-----------------------------
 1 file changed, 46 insertions(+), 95 deletions(-)

diff --git a/arch/openrisc/kernel/head.S b/arch/openrisc/kernel/head.S
index f147933..2346c5b 100644
--- a/arch/openrisc/kernel/head.S
+++ b/arch/openrisc/kernel/head.S
@@ -971,8 +971,6 @@ ENTRY(dtlb_miss_handler)
 	EXCEPTION_STORE_GPR2
 	EXCEPTION_STORE_GPR3
 	EXCEPTION_STORE_GPR4
-	EXCEPTION_STORE_GPR5
-	EXCEPTION_STORE_GPR6
 	/*
 	 * get EA of the miss
 	 */
@@ -980,91 +978,70 @@ ENTRY(dtlb_miss_handler)
 	/*
 	 * pmd = (pmd_t *)(current_pgd + pgd_index(daddr));
 	 */
-	GET_CURRENT_PGD(r3,r5)		// r3 is current_pgd, r5 is temp
+	GET_CURRENT_PGD(r3,r4)		// r3 is current_pgd, r4 is temp
 	l.srli	r4,r2,0x18		// >> PAGE_SHIFT + (PAGE_SHIFT - 2)
 	l.slli	r4,r4,0x2		// to get address << 2
-	l.add	r5,r4,r3		// r4 is pgd_index(daddr)
+	l.add	r3,r4,r3		// r4 is pgd_index(daddr)
 	/*
 	 * if (pmd_none(*pmd))
 	 *   goto pmd_none:
 	 */
-	tophys	(r4,r5)
+	tophys	(r4,r3)
 	l.lwz	r3,0x0(r4)		// get *pmd value
 	l.sfne	r3,r0
 	l.bnf	d_pmd_none
-	 l.andi	r3,r3,~PAGE_MASK //0x1fff		// ~PAGE_MASK
-	/*
-	 * if (pmd_bad(*pmd))
-	 *   pmd_clear(pmd)
-	 *   goto pmd_bad:
-	 */
-//	l.sfeq	r3,r0			// check *pmd value
-//	l.bf	d_pmd_good
-	l.addi	r3,r0,0xffffe000	// PAGE_MASK
-//	l.j	d_pmd_bad
-//	l.sw	0x0(r4),r0		// clear pmd
+	 l.addi	r3,r0,0xffffe000	// PAGE_MASK
+
 d_pmd_good:
 	/*
 	 * pte = *pte_offset(pmd, daddr);
 	 */
 	l.lwz	r4,0x0(r4)		// get **pmd value
 	l.and	r4,r4,r3		// & PAGE_MASK
-	l.srli	r5,r2,0xd		// >> PAGE_SHIFT, r2 == EEAR
-	l.andi	r3,r5,0x7ff		// (1UL << PAGE_SHIFT - 2) - 1
+	l.srli	r2,r2,0xd		// >> PAGE_SHIFT, r2 == EEAR
+	l.andi	r3,r2,0x7ff		// (1UL << PAGE_SHIFT - 2) - 1
 	l.slli	r3,r3,0x2		// to get address << 2
 	l.add	r3,r3,r4
-	l.lwz	r2,0x0(r3)		// this is pte at last
+	l.lwz	r3,0x0(r3)		// this is pte at last
 	/*
 	 * if (!pte_present(pte))
 	 */
-	l.andi	r4,r2,0x1
+	l.andi	r4,r3,0x1
 	l.sfne	r4,r0			// is pte present
 	l.bnf	d_pte_not_present
-	l.addi	r3,r0,0xffffe3fa	// PAGE_MASK | DTLB_UP_CONVERT_MASK
+	l.addi	r4,r0,0xffffe3fa	// PAGE_MASK | DTLB_UP_CONVERT_MASK
 	/*
 	 * fill DTLB TR register
 	 */
-	l.and	r4,r2,r3		// apply the mask
+	l.and	r4,r3,r4		// apply the mask
 	// Determine number of DMMU sets
-	l.mfspr r6, r0, SPR_DMMUCFGR
-	l.andi	r6, r6, SPR_DMMUCFGR_NTS
-	l.srli	r6, r6, SPR_DMMUCFGR_NTS_OFF
+	l.mfspr r2, r0, SPR_DMMUCFGR
+	l.andi	r2, r2, SPR_DMMUCFGR_NTS
+	l.srli	r2, r2, SPR_DMMUCFGR_NTS_OFF
 	l.ori	r3, r0, 0x1
-	l.sll	r3, r3, r6 	// r3 = number DMMU sets DMMUCFGR
-	l.addi	r6, r3, -1  	// r6 = nsets mask
-	l.and	r5, r5, r6	// calc offset:	 & (NUM_TLB_ENTRIES-1)
+	l.sll	r3, r3, r2 	// r3 = number DMMU sets DMMUCFGR
+	l.addi	r2, r3, -1  	// r2 = nsets mask
+	l.mfspr	r3, r0, SPR_EEAR_BASE
+	l.srli	r3, r3, 0xd	// >> PAGE_SHIFT
+	l.and	r2, r3, r2	// calc offset:	 & (NUM_TLB_ENTRIES-1)
 	                                                   //NUM_TLB_ENTRIES
-	l.mtspr	r5,r4,SPR_DTLBTR_BASE(0)
+	l.mtspr	r2,r4,SPR_DTLBTR_BASE(0)
 	/*
 	 * fill DTLB MR register
 	 */
-	l.mfspr	r2,r0,SPR_EEAR_BASE
-	l.addi	r3,r0,0xffffe000	// PAGE_MASK
-	l.and	r4,r2,r3		// apply PAGE_MASK to EA (__PHX__ do we really need this?)
-	l.ori	r4,r4,0x1		// set hardware valid bit: DTBL_MR entry
-	l.mtspr	r5,r4,SPR_DTLBMR_BASE(0)
+	l.slli	r3, r3, 0xd		/* << PAGE_SHIFT => EA & PAGE_MASK */
+	l.ori	r4,r3,0x1		// set hardware valid bit: DTBL_MR entry
+	l.mtspr	r2,r4,SPR_DTLBMR_BASE(0)
 
 	EXCEPTION_LOAD_GPR2
 	EXCEPTION_LOAD_GPR3
 	EXCEPTION_LOAD_GPR4
-	EXCEPTION_LOAD_GPR5
-	EXCEPTION_LOAD_GPR6
-	l.rfe
-d_pmd_bad:
-	l.nop	1
-	EXCEPTION_LOAD_GPR2
-	EXCEPTION_LOAD_GPR3
-	EXCEPTION_LOAD_GPR4
-	EXCEPTION_LOAD_GPR5
-	EXCEPTION_LOAD_GPR6
 	l.rfe
 d_pmd_none:
 d_pte_not_present:
 	EXCEPTION_LOAD_GPR2
 	EXCEPTION_LOAD_GPR3
 	EXCEPTION_LOAD_GPR4
-	EXCEPTION_LOAD_GPR5
-	EXCEPTION_LOAD_GPR6
 	EXCEPTION_HANDLE(_dtlb_miss_page_fault_handler)
 
 /* ==============================================[ ITLB miss handler ]=== */
@@ -1072,8 +1049,6 @@ ENTRY(itlb_miss_handler)
 	EXCEPTION_STORE_GPR2
 	EXCEPTION_STORE_GPR3
 	EXCEPTION_STORE_GPR4
-	EXCEPTION_STORE_GPR5
-	EXCEPTION_STORE_GPR6
 	/*
 	 * get EA of the miss
 	 */
@@ -1083,30 +1058,19 @@ ENTRY(itlb_miss_handler)
 	 * pmd = (pmd_t *)(current_pgd + pgd_index(daddr));
 	 *
 	 */
-	GET_CURRENT_PGD(r3,r5)		// r3 is current_pgd, r5 is temp
+	GET_CURRENT_PGD(r3,r4)		// r3 is current_pgd, r5 is temp
 	l.srli	r4,r2,0x18		// >> PAGE_SHIFT + (PAGE_SHIFT - 2)
 	l.slli	r4,r4,0x2		// to get address << 2
-	l.add	r5,r4,r3		// r4 is pgd_index(daddr)
+	l.add	r3,r4,r3		// r4 is pgd_index(daddr)
 	/*
 	 * if (pmd_none(*pmd))
 	 *   goto pmd_none:
 	 */
-	tophys	(r4,r5)
+	tophys	(r4,r3)
 	l.lwz	r3,0x0(r4)		// get *pmd value
 	l.sfne	r3,r0
 	l.bnf	i_pmd_none
-	l.andi	r3,r3,0x1fff		// ~PAGE_MASK
-	/*
-	 * if (pmd_bad(*pmd))
-	 *   pmd_clear(pmd)
-	 *   goto pmd_bad:
-	 */
-
-//	l.sfeq	r3,r0			// check *pmd value
-//	l.bf	i_pmd_good
-	l.addi	r3,r0,0xffffe000	// PAGE_MASK
-//	l.j	i_pmd_bad
-//	l.sw	0x0(r4),r0		// clear pmd
+	 l.addi	r3,r0,0xffffe000	// PAGE_MASK
 
 i_pmd_good:
 	/*
@@ -1115,35 +1079,36 @@ i_pmd_good:
 	 */
 	l.lwz	r4,0x0(r4)		// get **pmd value
 	l.and	r4,r4,r3		// & PAGE_MASK
-	l.srli	r5,r2,0xd		// >> PAGE_SHIFT, r2 == EEAR
-	l.andi	r3,r5,0x7ff		// (1UL << PAGE_SHIFT - 2) - 1
+	l.srli	r2,r2,0xd		// >> PAGE_SHIFT, r2 == EEAR
+	l.andi	r3,r2,0x7ff		// (1UL << PAGE_SHIFT - 2) - 1
 	l.slli	r3,r3,0x2		// to get address << 2
 	l.add	r3,r3,r4
-	l.lwz	r2,0x0(r3)		// this is pte at last
+	l.lwz	r3,0x0(r3)		// this is pte at last
 	/*
 	 * if (!pte_present(pte))
 	 *
 	 */
-	l.andi	r4,r2,0x1
+	l.andi	r4,r3,0x1
 	l.sfne	r4,r0			// is pte present
 	l.bnf	i_pte_not_present
-	l.addi	r3,r0,0xffffe03a	// PAGE_MASK | ITLB_UP_CONVERT_MASK
+	 l.addi	r4,r0,0xffffe03a	// PAGE_MASK | ITLB_UP_CONVERT_MASK
 	/*
 	 * fill ITLB TR register
 	 */
-	l.and	r4,r2,r3		// apply the mask
-	l.andi	r3,r2,0x7c0		// _PAGE_EXEC | _PAGE_SRE | _PAGE_SWE |  _PAGE_URE | _PAGE_UWE
-//	l.andi	r3,r2,0x400		// _PAGE_EXEC
+	l.and	r4,r3,r4		// apply the mask
+	l.andi	r3,r3,0x7c0		// _PAGE_EXEC | _PAGE_SRE | _PAGE_SWE |  _PAGE_URE | _PAGE_UWE
 	l.sfeq	r3,r0
 	l.bf	itlb_tr_fill //_workaround
 	// Determine number of IMMU sets
-	l.mfspr r6, r0, SPR_IMMUCFGR
-	l.andi	r6, r6, SPR_IMMUCFGR_NTS
-	l.srli	r6, r6, SPR_IMMUCFGR_NTS_OFF
+	l.mfspr r2, r0, SPR_IMMUCFGR
+	l.andi	r2, r2, SPR_IMMUCFGR_NTS
+	l.srli	r2, r2, SPR_IMMUCFGR_NTS_OFF
 	l.ori	r3, r0, 0x1
-	l.sll	r3, r3, r6 	// r3 = number IMMU sets IMMUCFGR
-	l.addi	r6, r3, -1  	// r6 = nsets mask
-	l.and	r5, r5, r6	// calc offset:	 & (NUM_TLB_ENTRIES-1)
+	l.sll	r3, r3, r2 	// r3 = number IMMU sets IMMUCFGR
+	l.addi	r2, r3, -1  	// r2 = nsets mask
+	l.mfspr	r3, r0, SPR_EEAR_BASE
+	l.srli	r3, r3, 0xd	// >> PAGE_SHIFT
+	l.and	r2, r3, r2	// calc offset:	 & (NUM_TLB_ENTRIES-1)
 
 /*
  * __PHX__ :: fixme
@@ -1155,38 +1120,24 @@ i_pmd_good:
 itlb_tr_fill_workaround:
 	l.ori	r4,r4,0xc0		// | (SPR_ITLBTR_UXE | ITLBTR_SXE)
 itlb_tr_fill:
-	l.mtspr	r5,r4,SPR_ITLBTR_BASE(0)
+	l.mtspr	r2,r4,SPR_ITLBTR_BASE(0)
 	/*
 	 * fill DTLB MR register
 	 */
-	l.mfspr	r2,r0,SPR_EEAR_BASE
-	l.addi	r3,r0,0xffffe000	// PAGE_MASK
-	l.and	r4,r2,r3		// apply PAGE_MASK to EA (__PHX__ do we really need this?)
-	l.ori	r4,r4,0x1		// set hardware valid bit: DTBL_MR entry
-	l.mtspr	r5,r4,SPR_ITLBMR_BASE(0)
+	l.slli	r3, r3, 0xd		/* << PAGE_SHIFT => EA & PAGE_MASK */
+	l.ori	r4,r3,0x1		// set hardware valid bit: ITBL_MR entry
+	l.mtspr	r2,r4,SPR_ITLBMR_BASE(0)
 
 	EXCEPTION_LOAD_GPR2
 	EXCEPTION_LOAD_GPR3
 	EXCEPTION_LOAD_GPR4
-	EXCEPTION_LOAD_GPR5
-	EXCEPTION_LOAD_GPR6
 	l.rfe
 
-i_pmd_bad:
-	l.nop	1
-	EXCEPTION_LOAD_GPR2
-	EXCEPTION_LOAD_GPR3
-	EXCEPTION_LOAD_GPR4
-	EXCEPTION_LOAD_GPR5
-	EXCEPTION_LOAD_GPR6
-	l.rfe
 i_pmd_none:
 i_pte_not_present:
 	EXCEPTION_LOAD_GPR2
 	EXCEPTION_LOAD_GPR3
 	EXCEPTION_LOAD_GPR4
-	EXCEPTION_LOAD_GPR5
-	EXCEPTION_LOAD_GPR6
 	EXCEPTION_HANDLE(_itlb_miss_page_fault_handler)
 
 /* ==============================================[ boot tlb handlers ]=== */
-- 
2.9.3

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#1587298 — [PATCH v4 19/24] openrisc: entry: Whitespace and comment cleanups

Cleanups to whitespace and add some comments. Reading through the delay
slot logic I noticed some things:
 - Delay slot instructions were not indented
 - Some comments are not lined up
 - Use tabs and spaces consistent with other code

No functional change

Signed-off-by: Stafford Horne <shorne@gmail.com>
---
 arch/openrisc/kernel/entry.S | 38 ++++++++++++++++++--------------------
 1 file changed, 18 insertions(+), 20 deletions(-)

diff --git a/arch/openrisc/kernel/entry.S b/arch/openrisc/kernel/entry.S
index ba1a361..daae2a4 100644
--- a/arch/openrisc/kernel/entry.S
+++ b/arch/openrisc/kernel/entry.S
@@ -228,7 +228,7 @@ EXCEPTION_ENTRY(_data_page_fault_handler)
 	 * DTLB miss handler in the CONFIG_GUARD_PROTECTED_CORE part
 	 */
 #ifdef CONFIG_OPENRISC_NO_SPR_SR_DSX
-	l.lwz   r6,PT_PC(r3)                  // address of an offending insn
+	l.lwz   r6,PT_PC(r3)               // address of an offending insn
 	l.lwz   r6,0(r6)                   // instruction that caused pf
 
 	l.srli  r6,r6,26                   // check opcode for jump insn
@@ -244,49 +244,47 @@ EXCEPTION_ENTRY(_data_page_fault_handler)
 	l.bf    8f
 	l.sfeqi r6,0x12                    // l.jalr
 	l.bf    8f
-
-	l.nop
+	 l.nop
 
 	l.j     9f
-	l.nop
-8:
+	 l.nop
 
-	l.lwz   r6,PT_PC(r3)                  // address of an offending insn
+8: // offending insn is in delay slot
+	l.lwz   r6,PT_PC(r3)               // address of an offending insn
 	l.addi  r6,r6,4
 	l.lwz   r6,0(r6)                   // instruction that caused pf
 	l.srli  r6,r6,26                   // get opcode
-9:
+9: // offending instruction opcode loaded in r6
 
 #else
 
-	l.mfspr r6,r0,SPR_SR		   // SR
-//	l.lwz	r6,PT_SR(r3)		   // ESR
-	l.andi	r6,r6,SPR_SR_DSX	   // check for delay slot exception
-	l.sfeqi	r6,0x1			   // exception happened in delay slot
-	l.bnf	7f
-	l.lwz	r6,PT_PC(r3)		   // address of an offending insn
+	l.mfspr r6,r0,SPR_SR               // SR
+	l.andi  r6,r6,SPR_SR_DSX           // check for delay slot exception
+	l.sfeqi r6,0x1                     // exception happened in delay slot
+	l.bnf   7f
+	 l.lwz  r6,PT_PC(r3)               // address of an offending insn
 
-	l.addi	r6,r6,4			   // offending insn is in delay slot
+	l.addi	r6,r6,4                    // offending insn is in delay slot
 7:
 	l.lwz   r6,0(r6)                   // instruction that caused pf
 	l.srli  r6,r6,26                   // check opcode for write access
 #endif
 
-	l.sfgeui r6,0x33		   // check opcode for write access
+	l.sfgeui r6,0x33                   // check opcode for write access
 	l.bnf   1f
 	l.sfleui r6,0x37
 	l.bnf   1f
 	l.ori   r6,r0,0x1                  // write access
 	l.j     2f
-	l.nop
+	 l.nop
 1:	l.ori   r6,r0,0x0                  // !write access
 2:
 
 	/* call fault.c handler in or32/mm/fault.c */
 	l.jal   do_page_fault
-	l.nop
+	 l.nop
 	l.j     _ret_from_exception
-	l.nop
+	 l.nop
 
 /* ---[ 0x400: Insn Page Fault exception ]------------------------------- */
 EXCEPTION_ENTRY(_itlb_miss_page_fault_handler)
@@ -306,9 +304,9 @@ EXCEPTION_ENTRY(_insn_page_fault_handler)
 
 	/* call fault.c handler in or32/mm/fault.c */
 	l.jal   do_page_fault
-	l.nop
+	 l.nop
 	l.j     _ret_from_exception
-	l.nop
+	 l.nop
 
 
 /* ---[ 0x500: Timer exception ]----------------------------------------- */
-- 
2.9.3

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