[PATCH v2 8/9] ARM: msm: Add SMP support for KPSSv2

From: Stephen Boyd
Date: Mon Dec 23 2013 - 19:42:16 EST


From: Rohit Vaswani <rvaswani@xxxxxxxxxxxxxx>

Implement support for the Krait CPU release sequence when the
CPUs are part of the second version of the Krait processor
subsystem.

Signed-off-by: Rohit Vaswani <rvaswani@xxxxxxxxxxxxxx>
Signed-off-by: Stephen Boyd <sboyd@xxxxxxxxxxxxxx>
---
arch/arm/mach-msm/platsmp.c | 123 ++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 123 insertions(+)

diff --git a/arch/arm/mach-msm/platsmp.c b/arch/arm/mach-msm/platsmp.c
index 4b13cd8..f07ad9d 100644
--- a/arch/arm/mach-msm/platsmp.c
+++ b/arch/arm/mach-msm/platsmp.c
@@ -38,7 +38,15 @@
#define L2DT_SLP BIT(3)
#define CLAMP BIT(0)

+#define APC_PWR_GATE_CTL 0x14
+#define BHS_CNT_SHIFT 24
+#define LDO_PWR_DWN_SHIFT 16
+#define LDO_BYP_SHIFT 8
+#define BHS_SEG_SHIFT 1
+#define BHS_EN BIT(0)
+
#define APCS_SAW2_VCTL 0x14
+#define APCS_SAW2_2_VCTL 0x1c

extern void secondary_startup(void);

@@ -157,6 +165,106 @@ out_acc:
return ret;
}

+static int kpssv2_release_secondary(unsigned int cpu)
+{
+ void __iomem *reg;
+ struct device_node *cpu_node, *l2_node, *acc_node, *saw_node;
+ void __iomem *l2_saw_base;
+ unsigned reg_val;
+ int ret;
+
+ cpu_node = of_get_cpu_node(cpu, NULL);
+ if (!cpu_node)
+ return -ENODEV;
+
+ acc_node = of_parse_phandle(cpu_node, "qcom,acc", 0);
+ if (!acc_node) {
+ ret = -ENODEV;
+ goto out_acc;
+ }
+
+ l2_node = of_parse_phandle(cpu_node, "next-level-cache", 0);
+ if (!l2_node) {
+ ret = -ENODEV;
+ goto out_l2;
+ }
+
+ saw_node = of_parse_phandle(l2_node, "qcom,saw", 0);
+ if (!saw_node) {
+ ret = -ENODEV;
+ goto out_saw;
+ }
+
+ reg = of_iomap(acc_node, 0);
+ if (!reg) {
+ ret = -ENOMEM;
+ goto out_map;
+ }
+
+ l2_saw_base = of_iomap(saw_node, 0);
+ if (!l2_saw_base) {
+ ret = -ENOMEM;
+ goto out_saw_map;
+ }
+
+ /* Turn on the BHS, turn off LDO Bypass and power down LDO */
+ reg_val = (64 << BHS_CNT_SHIFT) | (0x3f << LDO_PWR_DWN_SHIFT) | BHS_EN;
+ writel_relaxed(reg_val, reg + APC_PWR_GATE_CTL);
+ mb();
+ /* wait for the BHS to settle */
+ udelay(1);
+
+ /* Turn on BHS segments */
+ reg_val |= 0x3f << BHS_SEG_SHIFT;
+ writel_relaxed(reg_val, reg + APC_PWR_GATE_CTL);
+ mb();
+ /* wait for the BHS to settle */
+ udelay(1);
+
+ /* Finally turn on the bypass so that BHS supplies power */
+ reg_val |= 0x3f << LDO_BYP_SHIFT;
+ writel_relaxed(reg_val, reg + APC_PWR_GATE_CTL);
+
+ /* enable max phases */
+ writel_relaxed(0x10003, l2_saw_base + APCS_SAW2_2_VCTL);
+ mb();
+ udelay(50);
+
+ reg_val = COREPOR_RST | CLAMP;
+ writel_relaxed(reg_val, reg + APCS_CPU_PWR_CTL);
+ mb();
+ udelay(2);
+
+ reg_val &= ~CLAMP;
+ writel_relaxed(reg_val, reg + APCS_CPU_PWR_CTL);
+ mb();
+ udelay(2);
+
+ reg_val &= ~COREPOR_RST;
+ writel_relaxed(reg_val, reg + APCS_CPU_PWR_CTL);
+ mb();
+
+ reg_val |= CORE_PWRD_UP;
+ writel_relaxed(reg_val, reg + APCS_CPU_PWR_CTL);
+ mb();
+
+ ret = 0;
+
+ iounmap(l2_saw_base);
+out_saw_map:
+ iounmap(reg);
+out_map:
+ of_node_put(saw_node);
+out_saw:
+ of_node_put(l2_node);
+out_l2:
+ of_node_put(acc_node);
+out_acc:
+ of_node_put(cpu_node);
+
+ return ret;
+}
+
static DEFINE_PER_CPU(int, cold_boot_done);

static int msm_boot_secondary(unsigned int cpu, int (*func)(unsigned int))
@@ -201,6 +309,11 @@ static int kpssv1_boot_secondary(unsigned int cpu, struct task_struct *idle)
return msm_boot_secondary(cpu, kpssv1_release_secondary);
}

+static int kpssv2_boot_secondary(unsigned int cpu, struct task_struct *idle)
+{
+ return msm_boot_secondary(cpu, kpssv2_release_secondary);
+}
+
static void __init msm_smp_prepare_cpus(unsigned int max_cpus)
{
int cpu, map;
@@ -250,3 +363,13 @@ static struct smp_operations msm_smp_kpssv1_ops __initdata = {
#endif
};
CPU_METHOD_OF_DECLARE(msm_smp_kpssv1, "qcom,kpss-acc-v1", &msm_smp_kpssv1_ops);
+
+static struct smp_operations msm_smp_kpssv2_ops __initdata = {
+ .smp_prepare_cpus = msm_smp_prepare_cpus,
+ .smp_secondary_init = msm_secondary_init,
+ .smp_boot_secondary = kpssv2_boot_secondary,
+#ifdef CONFIG_HOTPLUG_CPU
+ .cpu_die = msm_cpu_die,
+#endif
+};
+CPU_METHOD_OF_DECLARE(msm_smp_kpssv2, "qcom,kpss-acc-v2", &msm_smp_kpssv2_ops);
--
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