From 577d104d85f05c1de6e56784a5da3e0fb4746f3a Mon Sep 17 00:00:00 2001 From: Geert Uytterhoeven Date: Thu, 4 Jun 2015 20:22:27 +0200 Subject: [PATCH] ARM: shmobile: R-Car: Improve documentation Add more SYSC register documentation. Use definitions instead of hardcoded numbers. Comment important operations. Signed-off-by: Geert Uytterhoeven Signed-off-by: Simon Horman --- arch/arm/mach-shmobile/pm-rcar.c | 46 ++++++++++++++++++++++---------- 1 file changed, 32 insertions(+), 14 deletions(-) diff --git a/arch/arm/mach-shmobile/pm-rcar.c b/arch/arm/mach-shmobile/pm-rcar.c index 00022ee56f80..56ea82a851cb 100644 --- a/arch/arm/mach-shmobile/pm-rcar.c +++ b/arch/arm/mach-shmobile/pm-rcar.c @@ -15,21 +15,35 @@ #include #include "pm-rcar.h" -/* SYSC */ -#define SYSCSR 0x00 -#define SYSCISR 0x04 -#define SYSCISCR 0x08 +/* SYSC Common */ +#define SYSCSR 0x00 /* SYSC Status Register */ +#define SYSCISR 0x04 /* Interrupt Status Register */ +#define SYSCISCR 0x08 /* Interrupt Status Clear Register */ +#define SYSCIER 0x0c /* Interrupt Enable Register */ +#define SYSCIMR 0x10 /* Interrupt Mask Register */ -#define PWRSR_OFFS 0x00 -#define PWROFFCR_OFFS 0x04 -#define PWRONCR_OFFS 0x0c -#define PWRER_OFFS 0x14 +/* SYSC Status Register */ +#define SYSCSR_PONENB 1 /* Ready for power resume requests */ +#define SYSCSR_POFFENB 0 /* Ready for power shutoff requests */ -#define SYSCSR_RETRIES 100 -#define SYSCSR_DELAY_US 1 +/* + * Power Control Register Offsets inside the register block for each domain + * Note: The "CR" registers for ARM cores exist on H1 only + * Use WFI to power off, CPG/APMU to resume ARM cores on R-Car Gen2 + */ +#define PWRSR_OFFS 0x00 /* Power Status Register */ +#define PWROFFCR_OFFS 0x04 /* Power Shutoff Control Register */ +#define PWROFFSR_OFFS 0x08 /* Power Shutoff Status Register */ +#define PWRONCR_OFFS 0x0c /* Power Resume Control Register */ +#define PWRONSR_OFFS 0x10 /* Power Resume Status Register */ +#define PWRER_OFFS 0x14 /* Power Shutoff/Resume Error */ -#define SYSCISR_RETRIES 1000 -#define SYSCISR_DELAY_US 1 + +#define SYSCSR_RETRIES 100 +#define SYSCSR_DELAY_US 1 + +#define SYSCISR_RETRIES 1000 +#define SYSCISR_DELAY_US 1 static void __iomem *rcar_sysc_base; static DEFINE_SPINLOCK(rcar_sysc_lock); /* SMP CPUs + I/O devices */ @@ -39,6 +53,7 @@ static int rcar_sysc_pwr_on_off(struct rcar_sysc_ch *sysc_ch, { int k; + /* Wait until SYSC is ready to accept a power request */ for (k = 0; k < SYSCSR_RETRIES; k++) { if (ioread32(rcar_sysc_base + SYSCSR) & (1 << sr_bit)) break; @@ -48,6 +63,7 @@ static int rcar_sysc_pwr_on_off(struct rcar_sysc_ch *sysc_ch, if (k == SYSCSR_RETRIES) return -EAGAIN; + /* Submit power shutoff or power resume request */ iowrite32(1 << sysc_ch->chan_bit, rcar_sysc_base + sysc_ch->chan_offs + reg_offs); @@ -56,12 +72,12 @@ static int rcar_sysc_pwr_on_off(struct rcar_sysc_ch *sysc_ch, static int rcar_sysc_pwr_off(struct rcar_sysc_ch *sysc_ch) { - return rcar_sysc_pwr_on_off(sysc_ch, 0, PWROFFCR_OFFS); + return rcar_sysc_pwr_on_off(sysc_ch, SYSCSR_POFFENB, PWROFFCR_OFFS); } static int rcar_sysc_pwr_on(struct rcar_sysc_ch *sysc_ch) { - return rcar_sysc_pwr_on_off(sysc_ch, 1, PWRONCR_OFFS); + return rcar_sysc_pwr_on_off(sysc_ch, SYSCSR_PONENB, PWRONCR_OFFS); } static int rcar_sysc_update(struct rcar_sysc_ch *sysc_ch, @@ -78,6 +94,7 @@ static int rcar_sysc_update(struct rcar_sysc_ch *sysc_ch, iowrite32(isr_mask, rcar_sysc_base + SYSCISCR); + /* Submit power shutoff or resume request until it was accepted */ do { ret = on_off_fn(sysc_ch); if (ret) @@ -87,6 +104,7 @@ static int rcar_sysc_update(struct rcar_sysc_ch *sysc_ch, sysc_ch->chan_offs + PWRER_OFFS); } while (status & chan_mask); + /* Wait until the power shutoff or resume request has completed * */ for (k = 0; k < SYSCISR_RETRIES; k++) { if (ioread32(rcar_sysc_base + SYSCISR) & isr_mask) break;