* Re:[PATCH] MIPS: Drop Loongson _CACHE_* definitions
2019-08-31 15:41 [PATCH] MIPS: Drop Loongson _CACHE_* definitions Paul Burton
@ 2019-09-01 2:41 ` 陈华才
2019-09-02 0:47 ` [PATCH] " Jiaxun Yang
2019-09-01 22:53 ` Philippe Mathieu-Daudé
` (2 subsequent siblings)
3 siblings, 1 reply; 6+ messages in thread
From: 陈华才 @ 2019-09-01 2:41 UTC (permalink / raw)
To: Paul Burton, linux-mips; +Cc: Paul Burton
Hi, Paul,
I found that _CACHE_CACHABLE_COHERENT is removed since 3.18, so this patch need to CC stable?
Huacai
------------------ Original ------------------
From: "Paul Burton"<paul.burton@mips.com>;
Date: Sat, Aug 31, 2019 11:41 PM
To: "linux-mips@vger.kernel.org"<linux-mips@vger.kernel.org>;
Cc: "Paul Burton"<pburton@wavecomp.com>; "Huacai Chen"<chenhc@lemote.com>;
Subject: [PATCH] MIPS: Drop Loongson _CACHE_* definitions
_CACHE_CACHABLE_NONCOHERENT is defined as 3<<_CACHE_SHIFT by default, so
there's no need to define it as such specifically for Loongson.
_CACHE_CACHABLE_COHERENT is not used anywhere in the kernel, so there's
no need to define it at all.
Finally the comment found alongside these definitions seems incorrect -
it suggests that we're defining _CACHE_CACHABLE_NONCOHERENT such that it
actually provides coherence, but the opposite seems to be true & instead
the unused _CACHE_CACHABLE_COHERENT is defined as the typically
incoherent value.
Delete the whole thing, which will have no effect on the compiled code
anyway.
Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: Huacai Chen <chenhc@lemote.com>
---
arch/mips/include/asm/pgtable-bits.h | 7 -------
1 file changed, 7 deletions(-)
diff --git a/arch/mips/include/asm/pgtable-bits.h b/arch/mips/include/asm/pgtable-bits.h
index 5f1ced8cba07..409ae01ed7be 100644
--- a/arch/mips/include/asm/pgtable-bits.h
+++ b/arch/mips/include/asm/pgtable-bits.h
@@ -221,13 +221,6 @@ static inline uint64_t pte_to_entrylo(unsigned long pte_val)
#define _CACHE_CACHABLE_NONCOHERENT (5<<_CACHE_SHIFT)
-#elif defined(CONFIG_CPU_LOONGSON3)
-
-/* Using COHERENT flag for NONCOHERENT doesn't hurt. */
-
-#define _CACHE_CACHABLE_NONCOHERENT (3<<_CACHE_SHIFT) /* LOONGSON */
-#define _CACHE_CACHABLE_COHERENT (3<<_CACHE_SHIFT) /* LOONGSON-3 */
-
#elif defined(CONFIG_MACH_INGENIC)
/* Ingenic uses the WA bit to achieve write-combine memory writes */
--
2.22.1
^ permalink raw reply related [flat|nested] 6+ messages in thread* Re: [PATCH] MIPS: Drop Loongson _CACHE_* definitions
2019-09-01 2:41 ` 陈华才
@ 2019-09-02 0:47 ` Jiaxun Yang
0 siblings, 0 replies; 6+ messages in thread
From: Jiaxun Yang @ 2019-09-02 0:47 UTC (permalink / raw)
To: 陈华才, Paul Burton, linux-mips; +Cc: Paul Burton
在 2019/9/1 10:41, 陈华才 写道:
> Hi, Paul,
>
> I found that _CACHE_CACHABLE_COHERENT is removed since 3.18, so this patch need to CC stable?
Hi Huacai
According to stable policy, stable tree won't accept this kind of
trivial fixes.
Thanks.
--
Jiaxun Yang
> Huacai
>
> ------------------ Original ------------------
> From: "Paul Burton"<paul.burton@mips.com>;
> Date: Sat, Aug 31, 2019 11:41 PM
> To: "linux-mips@vger.kernel.org"<linux-mips@vger.kernel.org>;
> Cc: "Paul Burton"<pburton@wavecomp.com>; "Huacai Chen"<chenhc@lemote.com>;
> Subject: [PATCH] MIPS: Drop Loongson _CACHE_* definitions
>
> _CACHE_CACHABLE_NONCOHERENT is defined as 3<<_CACHE_SHIFT by default, so
> there's no need to define it as such specifically for Loongson.
>
> _CACHE_CACHABLE_COHERENT is not used anywhere in the kernel, so there's
> no need to define it at all.
>
> Finally the comment found alongside these definitions seems incorrect -
> it suggests that we're defining _CACHE_CACHABLE_NONCOHERENT such that it
> actually provides coherence, but the opposite seems to be true & instead
> the unused _CACHE_CACHABLE_COHERENT is defined as the typically
> incoherent value.
>
> Delete the whole thing, which will have no effect on the compiled code
> anyway.
>
> Signed-off-by: Paul Burton <paul.burton@mips.com>
> Cc: Huacai Chen <chenhc@lemote.com>
> ---
>
> arch/mips/include/asm/pgtable-bits.h | 7 -------
> 1 file changed, 7 deletions(-)
>
> diff --git a/arch/mips/include/asm/pgtable-bits.h b/arch/mips/include/asm/pgtable-bits.h
> index 5f1ced8cba07..409ae01ed7be 100644
> --- a/arch/mips/include/asm/pgtable-bits.h
> +++ b/arch/mips/include/asm/pgtable-bits.h
> @@ -221,13 +221,6 @@ static inline uint64_t pte_to_entrylo(unsigned long pte_val)
>
> #define _CACHE_CACHABLE_NONCOHERENT (5<<_CACHE_SHIFT)
>
> -#elif defined(CONFIG_CPU_LOONGSON3)
> -
> -/* Using COHERENT flag for NONCOHERENT doesn't hurt. */
> -
> -#define _CACHE_CACHABLE_NONCOHERENT (3<<_CACHE_SHIFT) /* LOONGSON */
> -#define _CACHE_CACHABLE_COHERENT (3<<_CACHE_SHIFT) /* LOONGSON-3 */
> -
> #elif defined(CONFIG_MACH_INGENIC)
>
> /* Ingenic uses the WA bit to achieve write-combine memory writes */
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] MIPS: Drop Loongson _CACHE_* definitions
2019-08-31 15:41 [PATCH] MIPS: Drop Loongson _CACHE_* definitions Paul Burton
2019-09-01 2:41 ` 陈华才
@ 2019-09-01 22:53 ` Philippe Mathieu-Daudé
2019-09-02 0:51 ` Jiaxun Yang
2019-09-03 20:47 ` Paul Burton
3 siblings, 0 replies; 6+ messages in thread
From: Philippe Mathieu-Daudé @ 2019-09-01 22:53 UTC (permalink / raw)
To: Paul Burton, linux-mips; +Cc: Paul Burton, Huacai Chen
On 8/31/19 5:41 PM, Paul Burton wrote:
> _CACHE_CACHABLE_NONCOHERENT is defined as 3<<_CACHE_SHIFT by default, so
> there's no need to define it as such specifically for Loongson.
>
> _CACHE_CACHABLE_COHERENT is not used anywhere in the kernel, so there's
> no need to define it at all.
>
> Finally the comment found alongside these definitions seems incorrect -
> it suggests that we're defining _CACHE_CACHABLE_NONCOHERENT such that it
> actually provides coherence, but the opposite seems to be true & instead
> the unused _CACHE_CACHABLE_COHERENT is defined as the typically
> incoherent value.
>
> Delete the whole thing, which will have no effect on the compiled code
> anyway.
>
> Signed-off-by: Paul Burton <paul.burton@mips.com>
> Cc: Huacai Chen <chenhc@lemote.com>
> ---
>
> arch/mips/include/asm/pgtable-bits.h | 7 -------
> 1 file changed, 7 deletions(-)
>
> diff --git a/arch/mips/include/asm/pgtable-bits.h b/arch/mips/include/asm/pgtable-bits.h
> index 5f1ced8cba07..409ae01ed7be 100644
> --- a/arch/mips/include/asm/pgtable-bits.h
> +++ b/arch/mips/include/asm/pgtable-bits.h
> @@ -221,13 +221,6 @@ static inline uint64_t pte_to_entrylo(unsigned long pte_val)
>
> #define _CACHE_CACHABLE_NONCOHERENT (5<<_CACHE_SHIFT)
>
> -#elif defined(CONFIG_CPU_LOONGSON3)
> -
> -/* Using COHERENT flag for NONCOHERENT doesn't hurt. */
> -
> -#define _CACHE_CACHABLE_NONCOHERENT (3<<_CACHE_SHIFT) /* LOONGSON */
> -#define _CACHE_CACHABLE_COHERENT (3<<_CACHE_SHIFT) /* LOONGSON-3 */
> -
> #elif defined(CONFIG_MACH_INGENIC)
>
> /* Ingenic uses the WA bit to achieve write-combine memory writes */
>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] MIPS: Drop Loongson _CACHE_* definitions
2019-08-31 15:41 [PATCH] MIPS: Drop Loongson _CACHE_* definitions Paul Burton
2019-09-01 2:41 ` 陈华才
2019-09-01 22:53 ` Philippe Mathieu-Daudé
@ 2019-09-02 0:51 ` Jiaxun Yang
2019-09-03 20:47 ` Paul Burton
3 siblings, 0 replies; 6+ messages in thread
From: Jiaxun Yang @ 2019-09-02 0:51 UTC (permalink / raw)
To: Paul Burton, linux-mips; +Cc: Paul Burton, Huacai Chen
在 2019/8/31 23:41, Paul Burton 写道:
> _CACHE_CACHABLE_NONCOHERENT is defined as 3<<_CACHE_SHIFT by default, so
> there's no need to define it as such specifically for Loongson.
>
> _CACHE_CACHABLE_COHERENT is not used anywhere in the kernel, so there's
> no need to define it at all.
>
> Finally the comment found alongside these definitions seems incorrect -
> it suggests that we're defining _CACHE_CACHABLE_NONCOHERENT such that it
> actually provides coherence, but the opposite seems to be true & instead
> the unused _CACHE_CACHABLE_COHERENT is defined as the typically
> incoherent value.
>
> Delete the whole thing, which will have no effect on the compiled code
> anyway.
>
> Signed-off-by: Paul Burton <paul.burton@mips.com>
Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
> Cc: Huacai Chen <chenhc@lemote.com>
> ---
>
> arch/mips/include/asm/pgtable-bits.h | 7 -------
> 1 file changed, 7 deletions(-)
>
> diff --git a/arch/mips/include/asm/pgtable-bits.h b/arch/mips/include/asm/pgtable-bits.h
> index 5f1ced8cba07..409ae01ed7be 100644
> --- a/arch/mips/include/asm/pgtable-bits.h
> +++ b/arch/mips/include/asm/pgtable-bits.h
> @@ -221,13 +221,6 @@ static inline uint64_t pte_to_entrylo(unsigned long pte_val)
>
> #define _CACHE_CACHABLE_NONCOHERENT (5<<_CACHE_SHIFT)
>
> -#elif defined(CONFIG_CPU_LOONGSON3)
> -
> -/* Using COHERENT flag for NONCOHERENT doesn't hurt. */
> -
> -#define _CACHE_CACHABLE_NONCOHERENT (3<<_CACHE_SHIFT) /* LOONGSON */
> -#define _CACHE_CACHABLE_COHERENT (3<<_CACHE_SHIFT) /* LOONGSON-3 */
> -
> #elif defined(CONFIG_MACH_INGENIC)
>
> /* Ingenic uses the WA bit to achieve write-combine memory writes */
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] MIPS: Drop Loongson _CACHE_* definitions
2019-08-31 15:41 [PATCH] MIPS: Drop Loongson _CACHE_* definitions Paul Burton
` (2 preceding siblings ...)
2019-09-02 0:51 ` Jiaxun Yang
@ 2019-09-03 20:47 ` Paul Burton
3 siblings, 0 replies; 6+ messages in thread
From: Paul Burton @ 2019-09-03 20:47 UTC (permalink / raw)
To: Paul Burton; +Cc: linux-mips, Paul Burton, Huacai Chen, linux-mips
Hello,
Paul Burton wrote:
> _CACHE_CACHABLE_NONCOHERENT is defined as 3<<_CACHE_SHIFT by default, so
> there's no need to define it as such specifically for Loongson.
>
> _CACHE_CACHABLE_COHERENT is not used anywhere in the kernel, so there's
> no need to define it at all.
>
> Finally the comment found alongside these definitions seems incorrect -
> it suggests that we're defining _CACHE_CACHABLE_NONCOHERENT such that it
> actually provides coherence, but the opposite seems to be true & instead
> the unused _CACHE_CACHABLE_COHERENT is defined as the typically
> incoherent value.
>
> Delete the whole thing, which will have no effect on the compiled code
> anyway.
Applied to mips-next.
> commit 3d77a95fc03b
> https://git.kernel.org/mips/c/3d77a95fc03b
>
> Signed-off-by: Paul Burton <paul.burton@mips.com>
> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
> Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Thanks,
Paul
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^ permalink raw reply [flat|nested] 6+ messages in thread