Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1295899

Re: [PATCH] IRQ/Platform-MSI:Increase the maximum MSIs the MSI framework can support.

Show all headers | View raw

On Mon, 21 Dec 2015 11:18:25 +0800
MaJun <majun258@huawei.com> wrote:

> From: Ma Jun <majun258@huawei.com>
> 
> The current MSI framework can only support 256 platform MSIs.
> 
> But on Hisilicon platform, some network related devices has about 500
> wired interrupts.
> 
> To support these devices, we need a new maximum value more than 256.
> 
> Signed-off-by: Ma Jun <majun258@huawei.com>
> ---
>  drivers/base/platform-msi.c |    2 +-
>  1 files changed, 1 insertions(+), 1 deletions(-)
> 
> diff --git a/drivers/base/platform-msi.c b/drivers/base/platform-msi.c
> index a203896..9c00d3f 100644
> --- a/drivers/base/platform-msi.c
> +++ b/drivers/base/platform-msi.c
> @@ -24,7 +24,7 @@
>  #include <linux/msi.h>
>  #include <linux/slab.h>
>  
> -#define DEV_ID_SHIFT	24
> +#define DEV_ID_SHIFT	22
>  #define MAX_DEV_MSIS	(1 << (32 - DEV_ID_SHIFT))
>  
>  /*

If we bother doing that, why not directly aligning it with MSI-X and
allow up to 2048 interrupts per device? It is only an extra bit, and
that still leaves 21 bits worth of device IDs, while still having
hwirq as an unsigned long (32bit on 32bit architectures).

Thanks,

	M.

-- 
Without deviation from the norm, progress is not possible.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Back to linux.kernel | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

[PATCH] IRQ/Platform-MSI:Increase the maximum MSIs the MSI framework can support. MaJun <majun258@huawei.com> - 2015-12-21 04:20 +0100
  Re: [PATCH] IRQ/Platform-MSI:Increase the maximum MSIs the MSI  framework can support. Marc Zyngier <marc.zyngier@arm.com> - 2015-12-21 11:40 +0100
    Re: [PATCH] IRQ/Platform-MSI:Increase the maximum MSIs the MSI  framework can support. "majun (F)" <majun258@huawei.com> - 2015-12-22 03:50 +0100

csiph-web