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Groups > linux.kernel > #1551239
| From | Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
|---|---|
| Newsgroups | linux.kernel |
| Subject | [PATCH 4.9 28/83] clk: ti: omap36xx: Work around sprz319 advisory 2.1 |
| Date | 2017-01-04 21:30 +0100 |
| Message-ID | <sW0m7-1bZ-65@gated-at.bofh.it> (permalink) |
| References | <sW02J-12y-3@gated-at.bofh.it> |
| Organization | linux.* mail to news gateway |
4.9-stable review patch. If anyone has any objections, please let me know.
------------------
From: Richard Watts <rrw@kynesim.co.uk>
commit 035cd485a47dda64f25ccf8a90b11a07d0b7aa7a upstream.
The OMAP36xx DPLL5, driving EHCI USB, can be subject to a long-term
frequency drift. The frequency drift magnitude depends on the VCO update
rate, which is inversely proportional to the PLL divider. The kernel
DPLL configuration code results in a high value for the divider, leading
to a long term drift high enough to cause USB transmission errors. In
the worst case the USB PHY's ULPI interface can stop responding,
breaking USB operation completely. This manifests itself on the
Beagleboard xM by the LAN9514 reporting 'Cannot enable port 2. Maybe the
cable is bad?' in the kernel log.
Errata sprz319 advisory 2.1 documents PLL values that minimize the
drift. Use them automatically when DPLL5 is used for USB operation,
which we detect based on the requested clock rate. The clock framework
will still compute the PLL parameters and resulting rate as usual, but
the PLL M and N values will then be overridden. This can result in the
effective clock rate being slightly different than the rate cached by
the clock framework, but won't cause any adverse effect to USB
operation.
Signed-off-by: Richard Watts <rrw@kynesim.co.uk>
[Upported from v3.2 to v4.9]
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Tested-by: Ladislav Michl <ladis@linux-mips.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Cc: Adam Ford <aford173@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/clk/ti/clk-3xxx.c | 20 ++++++-------
drivers/clk/ti/clock.h | 9 ++++++
drivers/clk/ti/dpll.c | 19 ++++++++++++-
drivers/clk/ti/dpll3xxx.c | 67 ++++++++++++++++++++++++++++++++++++++++++++++
4 files changed, 104 insertions(+), 11 deletions(-)
--- a/drivers/clk/ti/clk-3xxx.c
+++ b/drivers/clk/ti/clk-3xxx.c
@@ -22,13 +22,6 @@
#include "clock.h"
-/*
- * DPLL5_FREQ_FOR_USBHOST: USBHOST and USBTLL are the only clocks
- * that are sourced by DPLL5, and both of these require this clock
- * to be at 120 MHz for proper operation.
- */
-#define DPLL5_FREQ_FOR_USBHOST 120000000
-
#define OMAP3430ES2_ST_DSS_IDLE_SHIFT 1
#define OMAP3430ES2_ST_HSOTGUSB_IDLE_SHIFT 5
#define OMAP3430ES2_ST_SSI_IDLE_SHIFT 8
@@ -546,14 +539,21 @@ void __init omap3_clk_lock_dpll5(void)
struct clk *dpll5_clk;
struct clk *dpll5_m2_clk;
+ /*
+ * Errata sprz319f advisory 2.1 documents a USB host clock drift issue
+ * that can be worked around using specially crafted dpll5 settings
+ * with a dpll5_m2 divider set to 8. Set the dpll5 rate to 8x the USB
+ * host clock rate, its .set_rate handler() will detect that frequency
+ * and use the errata settings.
+ */
dpll5_clk = clk_get(NULL, "dpll5_ck");
- clk_set_rate(dpll5_clk, DPLL5_FREQ_FOR_USBHOST);
+ clk_set_rate(dpll5_clk, OMAP3_DPLL5_FREQ_FOR_USBHOST * 8);
clk_prepare_enable(dpll5_clk);
- /* Program dpll5_m2_clk divider for no division */
+ /* Program dpll5_m2_clk divider */
dpll5_m2_clk = clk_get(NULL, "dpll5_m2_ck");
clk_prepare_enable(dpll5_m2_clk);
- clk_set_rate(dpll5_m2_clk, DPLL5_FREQ_FOR_USBHOST);
+ clk_set_rate(dpll5_m2_clk, OMAP3_DPLL5_FREQ_FOR_USBHOST);
clk_disable_unprepare(dpll5_m2_clk);
clk_disable_unprepare(dpll5_clk);
--- a/drivers/clk/ti/clock.h
+++ b/drivers/clk/ti/clock.h
@@ -257,11 +257,20 @@ long omap2_dpll_round_rate(struct clk_hw
unsigned long omap3_clkoutx2_recalc(struct clk_hw *hw,
unsigned long parent_rate);
+/*
+ * OMAP3_DPLL5_FREQ_FOR_USBHOST: USBHOST and USBTLL are the only clocks
+ * that are sourced by DPLL5, and both of these require this clock
+ * to be at 120 MHz for proper operation.
+ */
+#define OMAP3_DPLL5_FREQ_FOR_USBHOST 120000000
+
unsigned long omap3_dpll_recalc(struct clk_hw *hw, unsigned long parent_rate);
int omap3_dpll4_set_rate(struct clk_hw *clk, unsigned long rate,
unsigned long parent_rate);
int omap3_dpll4_set_rate_and_parent(struct clk_hw *hw, unsigned long rate,
unsigned long parent_rate, u8 index);
+int omap3_dpll5_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate);
void omap3_clk_lock_dpll5(void);
unsigned long omap4_dpll_regm4xen_recalc(struct clk_hw *hw,
--- a/drivers/clk/ti/dpll.c
+++ b/drivers/clk/ti/dpll.c
@@ -114,6 +114,18 @@ static const struct clk_ops omap3_dpll_c
.round_rate = &omap2_dpll_round_rate,
};
+static const struct clk_ops omap3_dpll5_ck_ops = {
+ .enable = &omap3_noncore_dpll_enable,
+ .disable = &omap3_noncore_dpll_disable,
+ .get_parent = &omap2_init_dpll_parent,
+ .recalc_rate = &omap3_dpll_recalc,
+ .set_rate = &omap3_dpll5_set_rate,
+ .set_parent = &omap3_noncore_dpll_set_parent,
+ .set_rate_and_parent = &omap3_noncore_dpll_set_rate_and_parent,
+ .determine_rate = &omap3_noncore_dpll_determine_rate,
+ .round_rate = &omap2_dpll_round_rate,
+};
+
static const struct clk_ops omap3_dpll_per_ck_ops = {
.enable = &omap3_noncore_dpll_enable,
.disable = &omap3_noncore_dpll_disable,
@@ -474,7 +486,12 @@ static void __init of_ti_omap3_dpll_setu
.modes = (1 << DPLL_LOW_POWER_BYPASS) | (1 << DPLL_LOCKED),
};
- of_ti_dpll_setup(node, &omap3_dpll_ck_ops, &dd);
+ if ((of_machine_is_compatible("ti,omap3630") ||
+ of_machine_is_compatible("ti,omap36xx")) &&
+ !strcmp(node->name, "dpll5_ck"))
+ of_ti_dpll_setup(node, &omap3_dpll5_ck_ops, &dd);
+ else
+ of_ti_dpll_setup(node, &omap3_dpll_ck_ops, &dd);
}
CLK_OF_DECLARE(ti_omap3_dpll_clock, "ti,omap3-dpll-clock",
of_ti_omap3_dpll_setup);
--- a/drivers/clk/ti/dpll3xxx.c
+++ b/drivers/clk/ti/dpll3xxx.c
@@ -838,3 +838,70 @@ int omap3_dpll4_set_rate_and_parent(stru
return omap3_noncore_dpll_set_rate_and_parent(hw, rate, parent_rate,
index);
}
+
+/* Apply DM3730 errata sprz319 advisory 2.1. */
+static bool omap3_dpll5_apply_errata(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct omap3_dpll5_settings {
+ unsigned int rate, m, n;
+ };
+
+ static const struct omap3_dpll5_settings precomputed[] = {
+ /*
+ * From DM3730 errata advisory 2.1, table 35 and 36.
+ * The N value is increased by 1 compared to the tables as the
+ * errata lists register values while last_rounded_field is the
+ * real divider value.
+ */
+ { 12000000, 80, 0 + 1 },
+ { 13000000, 443, 5 + 1 },
+ { 19200000, 50, 0 + 1 },
+ { 26000000, 443, 11 + 1 },
+ { 38400000, 25, 0 + 1 }
+ };
+
+ const struct omap3_dpll5_settings *d;
+ struct clk_hw_omap *clk = to_clk_hw_omap(hw);
+ struct dpll_data *dd;
+ unsigned int i;
+
+ for (i = 0; i < ARRAY_SIZE(precomputed); ++i) {
+ if (parent_rate == precomputed[i].rate)
+ break;
+ }
+
+ if (i == ARRAY_SIZE(precomputed))
+ return false;
+
+ d = &precomputed[i];
+
+ /* Update the M, N and rounded rate values and program the DPLL. */
+ dd = clk->dpll_data;
+ dd->last_rounded_m = d->m;
+ dd->last_rounded_n = d->n;
+ dd->last_rounded_rate = div_u64((u64)parent_rate * d->m, d->n);
+ omap3_noncore_dpll_program(clk, 0);
+
+ return true;
+}
+
+/**
+ * omap3_dpll5_set_rate - set rate for omap3 dpll5
+ * @hw: clock to change
+ * @rate: target rate for clock
+ * @parent_rate: rate of the parent clock
+ *
+ * Set rate for the DPLL5 clock. Apply the sprz319 advisory 2.1 on OMAP36xx if
+ * the DPLL is used for USB host (detected through the requested rate).
+ */
+int omap3_dpll5_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ if (rate == OMAP3_DPLL5_FREQ_FOR_USBHOST * 8) {
+ if (omap3_dpll5_apply_errata(hw, parent_rate))
+ return 0;
+ }
+
+ return omap3_noncore_dpll_set_rate(hw, rate, parent_rate);
+}
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[PATCH 4.9 00/83] 4.9.1-stable review Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-01-04 21:20 +0100
[PATCH 4.9 68/83] CIFS: Fix a possible memory corruption during reconnect Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-01-04 21:30 +0100
[PATCH 4.9 26/83] ALSA: hda - Gate the mic jack on HP Z1 Gen3 AiO Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-01-04 21:30 +0100
[PATCH 4.9 33/83] mm: Add a user_ns owner to mm_struct and fix ptrace permission checks Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-01-04 21:30 +0100
[PATCH 4.9 38/83] ext4: dont lock buffer in ext4_commit_super if holding spinlock Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-01-04 21:30 +0100
[PATCH 4.9 39/83] ext4: fix mballoc breakage with 64k block size Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-01-04 21:30 +0100
[PATCH 4.9 17/83] usb: gadget: f_uac2: fix error handling at afunc_bind Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-01-04 21:30 +0100
[PATCH 4.9 41/83] ext4: use more strict checks for inodes_per_block on mount Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-01-04 21:30 +0100
[PATCH 4.9 36/83] ptrace: Dont allow accessing an undumpable mm Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-01-04 21:30 +0100
[PATCH 4.9 56/83] PM / OPP: Pass opp_table to dev_pm_opp_put_regulator() Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-01-04 21:30 +0100
[PATCH 4.9 35/83] ptrace: Capture the ptracers creds not PT_PTRACE_CAP Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-01-04 21:30 +0100
[PATCH 4.9 42/83] ext4: fix in-superblock mount options processing Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-01-04 21:30 +0100
[PATCH 4.9 40/83] ext4: fix stack memory corruption with 64k block size Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-01-04 21:30 +0100
[PATCH 4.9 25/83] ALSA: hda - fix headset-mic problem on a Dell laptop Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-01-04 21:30 +0100
[PATCH 4.9 64/83] dm raid: fix discard support regression Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-01-04 21:30 +0100
[PATCH 4.9 31/83] splice: reinstate SIGPIPE/EPIPE handling Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-01-04 21:30 +0100
[PATCH 4.9 59/83] dm table: fix all_blk_mq inconsistency when an empty table is loaded Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-01-04 21:30 +0100
[PATCH 4.9 34/83] vfs,mm: fix return value of read() at s_maxbytes Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-01-04 21:30 +0100
[PATCH 4.9 54/83] mm, page_alloc: keep pcp count and list contents in sync if struct page is corrupted Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-01-04 21:30 +0100
[PATCH 4.9 32/83] block_dev: dont test bdev->bd_contains when it is not stable Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-01-04 21:30 +0100
[PATCH 4.9 13/83] USB: cdc-acm: add device id for GW Instek AFG-125 Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-01-04 21:30 +0100
[PATCH 4.9 12/83] USB: serial: kl5kusb105: fix open error path Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-01-04 21:30 +0100
[PATCH 4.9 30/83] fs: exec: apply CLOEXEC before changing dumpable task flags Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-01-04 21:30 +0100
[PATCH 4.9 29/83] exec: Ensure mm->user_ns contains the execed files Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-01-04 21:30 +0100
[PATCH 4.9 62/83] dm crypt: mark key as invalid until properly loaded Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-01-04 21:30 +0100
[PATCH 4.9 28/83] clk: ti: omap36xx: Work around sprz319 advisory 2.1 Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-01-04 21:30 +0100
[PATCH 4.9 66/83] ASoC: intel: Fix crash at suspend/resume without card registration Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-01-04 21:30 +0100
[PATCH 4.9 43/83] ext4: add sanity checking to count_overhead() Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-01-04 21:30 +0100
[PATCH 4.9 55/83] usb: gadget: composite: always set ep->mult to a sensible value Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-01-04 21:30 +0100
[PATCH 4.9 58/83] blk-mq: Do not invoke .queue_rq() for a stopped queue Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-01-04 21:30 +0100
Re: [PATCH 4.9 00/83] 4.9.1-stable review Shuah Khan <shuah.kh@samsung.com> - 2017-01-05 01:50 +0100
Re: [PATCH 4.9 00/83] 4.9.1-stable review Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-01-05 09:00 +0100
Re: [PATCH 4.9 00/83] 4.9.1-stable review Guenter Roeck <linux@roeck-us.net> - 2017-01-05 06:00 +0100
Re: [PATCH 4.9 00/83] 4.9.1-stable review Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-01-05 09:00 +0100
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