Re: [PATCH] ARM: rockchip: restore dapswjdp after suspend

From: Huang, Tao
Date: Wed May 20 2015 - 22:02:58 EST


Hi, Doug:

å 2015å05æ21æ 04:34, Doug Anderson åé:
> In the commit (0ea001d ARM: rockchip: disable dapswjdp during suspend)
> we made the assumption that we didn't need to restore dapswjdp after
> suspend because "the MASKROM will enable it back".
>
> It turns out that's not a safe assumption. In some cases (pending
> interrupts) it's possible that the WFI might act as a no-op and the
> MaskROM will never run.


I don't think this can happen. It seems we set PMU_GLOBAL_INT_DISABLE
bit, which means in power off flow, the IRQ will not accepted until the
ARM is power off. Do you see the SGRF_CPU_CON0[0] is 0 after resume?

Anyway, restore the value is okay, which make the code more symmetrically



Since we're changing the bit, we should
> restore it ourselves.
>
> Signed-off-by: Doug Anderson <dianders@xxxxxxxxxxxx>
> ---
> arch/arm/mach-rockchip/pm.c | 5 +++++
> 1 file changed, 5 insertions(+)
>
> diff --git a/arch/arm/mach-rockchip/pm.c b/arch/arm/mach-rockchip/pm.c
> index b0dcbe2..a7be465 100644
> --- a/arch/arm/mach-rockchip/pm.c
> +++ b/arch/arm/mach-rockchip/pm.c
> @@ -48,6 +48,7 @@ static struct regmap *sgrf_regmap;
>
> static u32 rk3288_pmu_pwr_mode_con;
> static u32 rk3288_sgrf_soc_con0;
> +static u32 rk3288_sgrf_cpu_con0;
>
> static inline u32 rk3288_l2_config(void)
> {
> @@ -70,6 +71,7 @@ static void rk3288_slp_mode_set(int level)
> {
> u32 mode_set, mode_set1;
>
> + regmap_read(sgrf_regmap, RK3288_SGRF_CPU_CON0, &rk3288_sgrf_cpu_con0);
> regmap_read(sgrf_regmap, RK3288_SGRF_SOC_CON0, &rk3288_sgrf_soc_con0);
>
> regmap_read(pmu_regmap, RK3288_PMU_PWRMODE_CON,
> @@ -129,6 +131,9 @@ static void rk3288_slp_mode_set(int level)
>
> static void rk3288_slp_mode_set_resume(void)
> {
> + regmap_write(sgrf_regmap, RK3288_SGRF_CPU_CON0,
> + rk3288_sgrf_cpu_con0 | SGRF_DAPDEVICEEN_WRITE);
> +
> regmap_write(pmu_regmap, RK3288_PMU_PWRMODE_CON,
> rk3288_pmu_pwr_mode_con);
>
>

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