[PATCH v2] OMAP: use fncpy to copy the PM code functions to SRAM
Jean Pihet
jean.pihet at newoldbits.com
Tue Jan 25 12:22:37 EST 2011
On Tue, Jan 25, 2011 at 11:33 AM, Dave Martin <dave.martin at linaro.org> wrote:
> On Mon, Jan 24, 2011 at 5:25 PM, Jean Pihet <jean.pihet at newoldbits.com> wrote:
>> Hi,
>>
>> On Mon, Jan 24, 2011 at 5:11 PM, Dave Martin <dave.martin at linaro.org> wrote:
>>> Hi there, I just spotted a couple of things merging your patch...
>>>
>>> On Tue, Jan 18, 2011 at 12:02 PM, <jean.pihet at newoldbits.com> wrote:
>>>> From: Jean Pihet <j-pihet at ti.com>
>>>>
>>>> The new fncpy API is better suited for copying some
>>>> code to SRAM at runtime. This patch changes the ad-hoc
>>>> code to the more generic fncpy API.
>>>>
>>>> Tested OK on OMAP3 in low power modes (RET/OFF)
>>>> using omap2plus_defconfig with !CONFIG_THUMB2_KERNEL.
>>>> Compile tested on OMAP1/2 using omap1_defconfig.
>>>>
>>>> Signed-off-by: Jean Pihet <j-pihet at ti.com>
>>>> ---
>>>> arch/arm/mach-omap1/pm.h | 6 +++---
>>>> arch/arm/mach-omap1/sleep.S | 3 +++
>>>> arch/arm/mach-omap1/sram.S | 1 +
>>>> arch/arm/mach-omap2/pm.h | 2 +-
>>>> arch/arm/mach-omap2/sleep24xx.S | 2 ++
>>>> arch/arm/mach-omap2/sleep34xx.S | 2 ++
>>>> arch/arm/mach-omap2/sram242x.S | 3 +++
>>>> arch/arm/mach-omap2/sram243x.S | 3 +++
>>>> arch/arm/mach-omap2/sram34xx.S | 1 +
>>>> arch/arm/plat-omap/include/plat/sram.h | 14 +++++++++++++-
>>>> arch/arm/plat-omap/sram.c | 14 +++++++++-----
>>>> 11 files changed, 41 insertions(+), 10 deletions(-)
>>>>
>>>> diff --git a/arch/arm/mach-omap1/pm.h b/arch/arm/mach-omap1/pm.h
>>>> index 56a6479..cd926dc 100644
>>>> --- a/arch/arm/mach-omap1/pm.h
>>>> +++ b/arch/arm/mach-omap1/pm.h
>>>> @@ -123,9 +123,9 @@ extern void allow_idle_sleep(void);
>>>> extern void omap1_pm_idle(void);
>>>> extern void omap1_pm_suspend(void);
>>>>
>>>> -extern void omap7xx_cpu_suspend(unsigned short, unsigned short);
>>>> -extern void omap1510_cpu_suspend(unsigned short, unsigned short);
>>>> -extern void omap1610_cpu_suspend(unsigned short, unsigned short);
>>>> +extern void omap7xx_cpu_suspend(unsigned long, unsigned long);
>>>> +extern void omap1510_cpu_suspend(unsigned long, unsigned long);
>>>> +extern void omap1610_cpu_suspend(unsigned long, unsigned long);
>>>> extern void omap7xx_idle_loop_suspend(void);
>>>> extern void omap1510_idle_loop_suspend(void);
>>>> extern void omap1610_idle_loop_suspend(void);
>>>> diff --git a/arch/arm/mach-omap1/sleep.S b/arch/arm/mach-omap1/sleep.S
>>>> index ef771ce..c875bdc 100644
>>>> --- a/arch/arm/mach-omap1/sleep.S
>>>> +++ b/arch/arm/mach-omap1/sleep.S
>>>> @@ -58,6 +58,7 @@
>>>> */
>>>>
>>>> #if defined(CONFIG_ARCH_OMAP730) || defined(CONFIG_ARCH_OMAP850)
>>>> + .align 3
>>>> ENTRY(omap7xx_cpu_suspend)
>>>>
>>>> @ save registers on stack
>>>> @@ -137,6 +138,7 @@ ENTRY(omap7xx_cpu_suspend_sz)
>>>> #endif /* CONFIG_ARCH_OMAP730 || CONFIG_ARCH_OMAP850 */
>>>>
>>>> #ifdef CONFIG_ARCH_OMAP15XX
>>>> + .align 3
>>>> ENTRY(omap1510_cpu_suspend)
>>>>
>>>> @ save registers on stack
>>>> @@ -211,6 +213,7 @@ ENTRY(omap1510_cpu_suspend_sz)
>>>> #endif /* CONFIG_ARCH_OMAP15XX */
>>>>
>>>> #if defined(CONFIG_ARCH_OMAP16XX)
>>>> + .align 3
>>>> ENTRY(omap1610_cpu_suspend)
>>>>
>>>> @ save registers on stack
>>>> diff --git a/arch/arm/mach-omap1/sram.S b/arch/arm/mach-omap1/sram.S
>>>> index 7724e52..692587d 100644
>>>> --- a/arch/arm/mach-omap1/sram.S
>>>> +++ b/arch/arm/mach-omap1/sram.S
>>>> @@ -18,6 +18,7 @@
>>>> /*
>>>> * Reprograms ULPD and CKCTL.
>>>> */
>>>> + .align 3
>>>> ENTRY(omap1_sram_reprogram_clock)
>>>> stmfd sp!, {r0 - r12, lr} @ save registers on stack
>>>>
>>>> diff --git a/arch/arm/mach-omap2/pm.h b/arch/arm/mach-omap2/pm.h
>>>> index 1c1b0ab..39580e6 100644
>>>> --- a/arch/arm/mach-omap2/pm.h
>>>> +++ b/arch/arm/mach-omap2/pm.h
>>>> @@ -92,7 +92,7 @@ extern void omap24xx_idle_loop_suspend(void);
>>>> extern void omap24xx_cpu_suspend(u32 dll_ctrl, void __iomem *sdrc_dlla_ctrl,
>>>> void __iomem *sdrc_power);
>>>> extern void omap34xx_cpu_suspend(u32 *addr, int save_state);
>>>> -extern void save_secure_ram_context(u32 *addr);
>>>> +extern int save_secure_ram_context(u32 *addr);
>>>> extern void omap3_save_scratchpad_contents(void);
>>>>
>>>> extern unsigned int omap24xx_idle_loop_suspend_sz;
>>>> diff --git a/arch/arm/mach-omap2/sleep24xx.S b/arch/arm/mach-omap2/sleep24xx.S
>>>> index c7780cc..b5071a4 100644
>>>> --- a/arch/arm/mach-omap2/sleep24xx.S
>>>> +++ b/arch/arm/mach-omap2/sleep24xx.S
>>>> @@ -47,6 +47,7 @@
>>>> * Note: This code get's copied to internal SRAM at boot. When the OMAP
>>>> * wakes up it continues execution at the point it went to sleep.
>>>> */
>>>> + .align 3
>>>> ENTRY(omap24xx_idle_loop_suspend)
>>>> stmfd sp!, {r0, lr} @ save registers on stack
>>>> mov r0, #0 @ clear for mcr setup
>>>> @@ -82,6 +83,7 @@ ENTRY(omap24xx_idle_loop_suspend_sz)
>>>> * The DLL load value is not kept in RETENTION or OFF. It needs to be restored
>>>> * at wake
>>>> */
>>>> + .align 3
>>>> ENTRY(omap24xx_cpu_suspend)
>>>> stmfd sp!, {r0 - r12, lr} @ save registers on stack
>>>> mov r3, #0x0 @ clear for mcr call
>>>> diff --git a/arch/arm/mach-omap2/sleep34xx.S b/arch/arm/mach-omap2/sleep34xx.S
>>>> index 98d8232..951a0be 100644
>>>> --- a/arch/arm/mach-omap2/sleep34xx.S
>>>> +++ b/arch/arm/mach-omap2/sleep34xx.S
>>>> @@ -118,6 +118,7 @@ ENTRY(enable_omap3630_toggle_l2_on_restore)
>>>>
>>>> .text
>>>> /* Function to call rom code to save secure ram context */
>>>> + .align 3
>>>> ENTRY(save_secure_ram_context)
>>>> stmfd sp!, {r1-r12, lr} @ save registers on stack
>>>> adr r3, api_params @ r3 points to parameters
>>>> @@ -169,6 +170,7 @@ ENTRY(save_secure_ram_context_sz)
>>>> * depending on the low power mode (non-OFF vs OFF modes),
>>>> * cf. 'Resume path for xxx mode' comments.
>>>> */
>>>> + .align 3
>>>> ENTRY(omap34xx_cpu_suspend)
>>>> stmfd sp!, {r0-r12, lr} @ save registers on stack
>>>>
>>>> diff --git a/arch/arm/mach-omap2/sram242x.S b/arch/arm/mach-omap2/sram242x.S
>>>> index 055310c..ff9b9db 100644
>>>> --- a/arch/arm/mach-omap2/sram242x.S
>>>> +++ b/arch/arm/mach-omap2/sram242x.S
>>>> @@ -39,6 +39,7 @@
>>>>
>>>> .text
>>>>
>>>> + .align 3
>>>> ENTRY(omap242x_sram_ddr_init)
>>>> stmfd sp!, {r0 - r12, lr} @ save registers on stack
>>>>
>>>> @@ -143,6 +144,7 @@ ENTRY(omap242x_sram_ddr_init_sz)
>>>> * r0 = [PRCM_FULL | PRCM_HALF] r1 = SDRC_DLLA_CTRL value r2 = [DDR | SDR]
>>>> * PRCM_FULL = 2, PRCM_HALF = 1, DDR = 1, SDR = 0
>>>> */
>>>> + .align 3
>>>> ENTRY(omap242x_sram_reprogram_sdrc)
>>>> stmfd sp!, {r0 - r10, lr} @ save registers on stack
>>>> mov r3, #0x0 @ clear for mrc call
>>>> @@ -238,6 +240,7 @@ ENTRY(omap242x_sram_reprogram_sdrc_sz)
>>>> /*
>>>> * Set dividers and pll. Also recalculate DLL value for DDR and unlock mode.
>>>> */
>>>> + .align 3
>>>> ENTRY(omap242x_sram_set_prcm)
>>>> stmfd sp!, {r0-r12, lr} @ regs to stack
>>>> adr r4, pbegin @ addr of preload start
>>>> diff --git a/arch/arm/mach-omap2/sram243x.S b/arch/arm/mach-omap2/sram243x.S
>>>> index f900758..7673020 100644
>>>> --- a/arch/arm/mach-omap2/sram243x.S
>>>> +++ b/arch/arm/mach-omap2/sram243x.S
>>>> @@ -39,6 +39,7 @@
>>>>
>>>> .text
>>>>
>>>> + .align 3
>>>> ENTRY(omap243x_sram_ddr_init)
>>>> stmfd sp!, {r0 - r12, lr} @ save registers on stack
>>>>
>>>> @@ -143,6 +144,7 @@ ENTRY(omap243x_sram_ddr_init_sz)
>>>> * r0 = [PRCM_FULL | PRCM_HALF] r1 = SDRC_DLLA_CTRL value r2 = [DDR | SDR]
>>>> * PRCM_FULL = 2, PRCM_HALF = 1, DDR = 1, SDR = 0
>>>> */
>>>> + .align 3
>>>> ENTRY(omap243x_sram_reprogram_sdrc)
>>>> stmfd sp!, {r0 - r10, lr} @ save registers on stack
>>>> mov r3, #0x0 @ clear for mrc call
>>>> @@ -238,6 +240,7 @@ ENTRY(omap243x_sram_reprogram_sdrc_sz)
>>>> /*
>>>> * Set dividers and pll. Also recalculate DLL value for DDR and unlock mode.
>>>> */
>>>> + .align 3
>>>> ENTRY(omap243x_sram_set_prcm)
>>>> stmfd sp!, {r0-r12, lr} @ regs to stack
>>>> adr r4, pbegin @ addr of preload start
>>>> diff --git a/arch/arm/mach-omap2/sram34xx.S b/arch/arm/mach-omap2/sram34xx.S
>>>> index 7f893a2..25011ca 100644
>>>> --- a/arch/arm/mach-omap2/sram34xx.S
>>>> +++ b/arch/arm/mach-omap2/sram34xx.S
>>>> @@ -111,6 +111,7 @@
>>>> * since it will cause the ARM MMU to attempt to walk the page tables.
>>>> * These crashes may be intermittent.
>>>> */
>>>> + .align 3
>>>> ENTRY(omap3_sram_configure_core_dpll)
>>>> stmfd sp!, {r1-r12, lr} @ store regs to stack
>>>>
>>>> diff --git a/arch/arm/plat-omap/include/plat/sram.h b/arch/arm/plat-omap/include/plat/sram.h
>>>> index 9967d5e..d673f2c 100644
>>>> --- a/arch/arm/plat-omap/include/plat/sram.h
>>>> +++ b/arch/arm/plat-omap/include/plat/sram.h
>>>> @@ -12,7 +12,19 @@
>>>> #define __ARCH_ARM_OMAP_SRAM_H
>>>>
>>>> #ifndef __ASSEMBLY__
>>>> -extern void * omap_sram_push(void * start, unsigned long size);
>>>> +#include <asm/fncpy.h>
>>>> +
>>>> +extern void *omap_sram_push_address(unsigned long size);
>>>> +
>>>> +/* Macro to push a function to the internal SRAM, using the fncpy API */
>>>> +#define omap_sram_push(funcp, size) ({ \
>>>> + typeof(&funcp) _res = NULL; \
>>>
>>> 1) For fncpy() itself, I decided not to take the address of funcp
>>> inside the macro: the reason for this was that if you do this, the
>>> macro will silently do something silly if called with a function
>>> pointer instead of the function itself -- i.e., some memory starting
>>> at the stored function pointer itself will be copied instead of the
>>> function body.
>>>
>>> Forcing the caller to supply the '&' is a bit ugly, but I decided it
>>> was preferable from a safety standpoint.
>>>
>>> This doesn't necessarily mean that omap_sram_push can't add the '&',
>>> but if you do, you need to be careful how the macro is called. It
>>> will work for all existing uses of omap_sram_push, IIUC.
>> I am OK with that.
>> In the first place it was not obvious that the '&' was needed but the
>> compiler quickly reminded me about it. The type checking is one of the
>> advantages of the new API.
>>
>>>
>>> 2) Should this be &(funcp)? This will only matter for pretty weird
>>> uses though. Currently most weird uses won't work properly anyway,
>>> because of (1). So this might not be much of a concern.
>>>
>>>> + void *_sram_address = omap_sram_push_address(size); \
>>>> + if (_sram_address) \
>>>> + _res = fncpy(_sram_address, &funcp, size); \
>>>
>>> &(funcp)
>> Yes that is correct but the current code does not have problem since
>> the functions to push have 'non-weird' types.
>> If needed I can change that.
>
> Fair enough. Because of the way omap_sram_push is used I think this
> isn't a significant risk -- just thought it was worth pointing out.
OK!
Just sent an extra patch '[PATCH] OMAP: fix fncpy API call' for completeness.
> Cheers
> ---Dave
>
Cheers,
Jean
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