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| author | Geert Uytterhoeven <geert+renesas@glider.be> | 2016-12-05 13:39:38 +0300 |
|---|---|---|
| committer | Simon Horman <horms+renesas@verge.net.au> | 2017-01-03 12:50:38 +0300 |
| commit | 10f778a97845e8b10af8878af99c9cfe6c31baf9 (patch) | |
| tree | 66a68a5aefdad6b2f578d3c127fa876c74a1c68f | |
| parent | 460d4117a4714f3e9ae600974df03632139728ec (diff) | |
| download | linux-10f778a97845e8b10af8878af99c9cfe6c31baf9.tar.xz | |
ARM: shmobile: apmu: Add debug resource reset for secondary CPU boot
In debug mode (MD21=1), reset requests derived from power-shutoff to the
AP-system CPU cores must be enabled before the AP-system CPU cores
resume from power-shutoff for the first time. Else resume may fail,
causing the system to hang during boot.
As setting these bits is a no-op in normal mode, there's no need to
check the actual state of MD21 first.
Inspired by CPU-specific patches in the BSP by Hisashi Nakamura
<hisashi.nakamura.ak@renesas.com>.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Hiep Cao Minh <cm-hiep@jinso.co.jp>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
| -rw-r--r-- | arch/arm/mach-shmobile/platsmp-apmu.c | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/arch/arm/mach-shmobile/platsmp-apmu.c b/arch/arm/mach-shmobile/platsmp-apmu.c index 933f9b902405..7e4ca6788be5 100644 --- a/arch/arm/mach-shmobile/platsmp-apmu.c +++ b/arch/arm/mach-shmobile/platsmp-apmu.c @@ -35,12 +35,18 @@ static struct { #define PSTR_OFFS 0x40 /* Power Status Register */ #define CPUNCR_OFFS(n) (0x100 + (0x10 * (n))) /* CPUn Power Status Control Register */ +#define DBGRCR_OFFS 0x180 /* Debug Resource Reset Control Reg. */ /* Power Status Register */ #define CPUNST(r, n) (((r) >> (n * 4)) & 3) /* CPUn Status Bit */ #define CPUST_RUN 0 /* Run Mode */ #define CPUST_STANDBY 3 /* CoreStandby Mode */ +/* Debug Resource Reset Control Register */ +#define DBGCPUREN BIT(24) /* CPU Other Reset Request Enable */ +#define DBGCPUNREN(n) BIT((n) + 20) /* CPUn Reset Request Enable */ +#define DBGCPUPREN BIT(19) /* CPU Peripheral Reset Req. Enable */ + static int __maybe_unused apmu_power_on(void __iomem *p, int bit) { /* request power on */ @@ -84,6 +90,8 @@ static int __maybe_unused apmu_wrap(int cpu, int (*fn)(void __iomem *p, int cpu) #ifdef CONFIG_SMP static void apmu_init_cpu(struct resource *res, int cpu, int bit) { + u32 x; + if ((cpu >= ARRAY_SIZE(apmu_cpus)) || apmu_cpus[cpu].iomem) return; @@ -91,6 +99,11 @@ static void apmu_init_cpu(struct resource *res, int cpu, int bit) apmu_cpus[cpu].bit = bit; pr_debug("apmu ioremap %d %d %pr\n", cpu, bit, res); + + /* Setup for debug mode */ + x = readl(apmu_cpus[cpu].iomem + DBGRCR_OFFS); + x |= DBGCPUREN | DBGCPUNREN(bit) | DBGCPUPREN; + writel(x, apmu_cpus[cpu].iomem + DBGRCR_OFFS); } static void apmu_parse_cfg(void (*fn)(struct resource *res, int cpu, int bit), |