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SubjectRe: [PATCH 1/3] pm: at91: pm_slowclock: fix suspend/resume hang up in timeouts
Le 05/02/2015 07:00, Wenyou Yang a écrit :
> From: Sylvain Rochet <sylvain.rochet@finsecur.com>
>
> Removed timeout on XTAL, PLL lock and Master Clock Ready, hang if
> something went wrong instead of continuing in unknown condition. There
> is not much we can do if a PLL lock never ends, we are running in SRAM
> and we will not be able to connect back the sdram or ddram in order to
> be able to fire up a message or just panic.
>
> As a bonus, not decounting the timeout register in slow clock mode
> reduce cumulated suspend time and resume time from ~17ms to ~15ms.
>
> Signed-off-by: Sylvain Rochet <sylvain.rochet@finsecur.com>
> Acked-by: Wenyou.Yang <wenyou.yang@atmel.com>

Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>

and stacked in at91-4.0-fixes.
thanks!

> ---
> arch/arm/mach-at91/pm_slowclock.S | 33 ++++-----------------------------
> 1 file changed, 4 insertions(+), 29 deletions(-)
>
> diff --git a/arch/arm/mach-at91/pm_slowclock.S b/arch/arm/mach-at91/pm_slowclock.S
> index 2001877..79dfdbe 100644
> --- a/arch/arm/mach-at91/pm_slowclock.S
> +++ b/arch/arm/mach-at91/pm_slowclock.S
> @@ -34,11 +34,6 @@
> */
> #undef SLOWDOWN_MASTER_CLOCK
>
> -#define MCKRDY_TIMEOUT 1000
> -#define MOSCRDY_TIMEOUT 1000
> -#define PLLALOCK_TIMEOUT 1000
> -#define PLLBLOCK_TIMEOUT 1000
> -
> pmc .req r0
> sdramc .req r1
> ramc1 .req r2
> @@ -50,56 +45,36 @@ tmp2 .req r5
> * Wait until master clock is ready (after switching master clock source)
> */
> .macro wait_mckrdy
> - mov tmp2, #MCKRDY_TIMEOUT
> -1: sub tmp2, tmp2, #1
> - cmp tmp2, #0
> - beq 2f
> - ldr tmp1, [pmc, #AT91_PMC_SR]
> +1: ldr tmp1, [pmc, #AT91_PMC_SR]
> tst tmp1, #AT91_PMC_MCKRDY
> beq 1b
> -2:
> .endm
>
> /*
> * Wait until master oscillator has stabilized.
> */
> .macro wait_moscrdy
> - mov tmp2, #MOSCRDY_TIMEOUT
> -1: sub tmp2, tmp2, #1
> - cmp tmp2, #0
> - beq 2f
> - ldr tmp1, [pmc, #AT91_PMC_SR]
> +1: ldr tmp1, [pmc, #AT91_PMC_SR]
> tst tmp1, #AT91_PMC_MOSCS
> beq 1b
> -2:
> .endm
>
> /*
> * Wait until PLLA has locked.
> */
> .macro wait_pllalock
> - mov tmp2, #PLLALOCK_TIMEOUT
> -1: sub tmp2, tmp2, #1
> - cmp tmp2, #0
> - beq 2f
> - ldr tmp1, [pmc, #AT91_PMC_SR]
> +1: ldr tmp1, [pmc, #AT91_PMC_SR]
> tst tmp1, #AT91_PMC_LOCKA
> beq 1b
> -2:
> .endm
>
> /*
> * Wait until PLLB has locked.
> */
> .macro wait_pllblock
> - mov tmp2, #PLLBLOCK_TIMEOUT
> -1: sub tmp2, tmp2, #1
> - cmp tmp2, #0
> - beq 2f
> - ldr tmp1, [pmc, #AT91_PMC_SR]
> +1: ldr tmp1, [pmc, #AT91_PMC_SR]
> tst tmp1, #AT91_PMC_LOCKB
> beq 1b
> -2:
> .endm
>
> .text
>


--
Nicolas Ferre


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