Messages in this thread Patch in this message | | | From | Andreas Färber <> | Subject | [PATCH v3 25/25] ARM: owl: smp: Reimplement SPS power-gating for CPU2 and CPU3 | Date | Tue, 28 Feb 2017 07:35:35 +0100 |
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Bring up the two remaining CPUs.
Based on LeMaker linux-actions tree.
Signed-off-by: Andreas Färber <afaerber@suse.de> --- v3: new arch/arm/mach-actions/platsmp.c | 67 +++++++++++++++++++++++++++++++++++++++-- 1 file changed, 65 insertions(+), 2 deletions(-)
diff --git a/arch/arm/mach-actions/platsmp.c b/arch/arm/mach-actions/platsmp.c index 9d3601e..45b4bc5 100644 --- a/arch/arm/mach-actions/platsmp.c +++ b/arch/arm/mach-actions/platsmp.c @@ -28,7 +28,15 @@ #define OWL_CPUx_FLAG_BOOT 0x55aa +#define OWL_SPS_PG_CTL 0x0 + +#define OWL_SPS_PG_CTL_PWR_CPU2 BIT(5) +#define OWL_SPS_PG_CTL_PWR_CPU3 BIT(6) +#define OWL_SPS_PG_CTL_ACK_CPU2 BIT(21) +#define OWL_SPS_PG_CTL_ACK_CPU3 BIT(22) + static void __iomem *scu_base_addr; +static void __iomem *sps_base_addr; static void __iomem *timer_base_addr; static int ncores; @@ -42,6 +50,39 @@ static void write_pen_release(int val) outer_clean_range(__pa(&pen_release), __pa(&pen_release + 1)); } +/* The generic PM domain driver is not available this early. */ +static int owl_sps_set_pg(u32 pwr_mask, u32 ack_mask, bool enable) +{ + u32 val; + bool ack; + int timeout; + + val = readl(sps_base_addr + OWL_SPS_PG_CTL); + ack = val & ack_mask; + if (ack == enable) + return 0; + + if (enable) + val |= pwr_mask; + else + val &= ~pwr_mask; + + writel(val, sps_base_addr + OWL_SPS_PG_CTL); + + for (timeout = 5000; timeout > 0; timeout -= 50) { + val = readl(sps_base_addr + OWL_SPS_PG_CTL); + if ((val & ack_mask) == (enable ? ack_mask : 0)) + break; + udelay(50); + } + if (timeout <= 0) + return -ETIMEDOUT; + + udelay(10); + + return 0; +} + static void s500_smp_secondary_init(unsigned int cpu) { /* @@ -58,14 +99,24 @@ void owl_secondary_startup(void); static int s500_wakeup_secondary(unsigned int cpu) { + int ret; + if (cpu > 3) return -EINVAL; switch (cpu) { case 2: + ret = owl_sps_set_pg(OWL_SPS_PG_CTL_PWR_CPU2, + OWL_SPS_PG_CTL_ACK_CPU2, true); + if (ret) + return ret; + break; case 3: - /* CPU2/3 are power-gated */ - return -EINVAL; + ret = owl_sps_set_pg(OWL_SPS_PG_CTL_PWR_CPU3, + OWL_SPS_PG_CTL_ACK_CPU3, true); + if (ret) + return ret; + break; } /* wait for CPUx to run to WFE instruction */ @@ -133,6 +184,18 @@ static void __init s500_smp_prepare_cpus(unsigned int max_cpus) return; } + node = of_find_compatible_node(NULL, NULL, "actions,s500-sps"); + if (!node) { + pr_err("%s: missing sps\n", __func__); + return; + } + + sps_base_addr = of_iomap(node, 0); + if (!sps_base_addr) { + pr_err("%s: could not map sps registers\n", __func__); + return; + } + if (read_cpuid_part() == ARM_CPU_PART_CORTEX_A9) { node = of_find_compatible_node(NULL, NULL, "arm,cortex-a9-scu"); if (!node) { -- 2.10.2
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