ARM: OMAP4: PM: Add L2X0 cache lowpower support
When MPUSS hits off-mode, L2 cache is lost. This patch adds L2X0
necessary maintenance operations and context restoration in the
low power code.
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: Jean Pihet <j-pihet@ti.com>
Reviewed-by: Kevin Hilman <khilman@ti.com>
Tested-by: Vishwanath BS <vishwanath.bs@ti.com>
Signed-off-by: Kevin Hilman <khilman@ti.com>
diff --git a/arch/arm/mach-omap2/omap-mpuss-lowpower.c b/arch/arm/mach-omap2/omap-mpuss-lowpower.c
index f9bb2b3..907a048f 100644
--- a/arch/arm/mach-omap2/omap-mpuss-lowpower.c
+++ b/arch/arm/mach-omap2/omap-mpuss-lowpower.c
@@ -49,6 +49,7 @@
#include <asm/system.h>
#include <asm/pgalloc.h>
#include <asm/suspend.h>
+#include <asm/hardware/cache-l2x0.h>
#include <plat/omap44xx.h>
@@ -63,10 +64,12 @@
struct powerdomain *pwrdm;
void __iomem *scu_sar_addr;
void __iomem *wkup_sar_addr;
+ void __iomem *l2x0_sar_addr;
};
static DEFINE_PER_CPU(struct omap4_cpu_pm_info, omap4_pm_info);
static struct powerdomain *mpuss_pd;
+static void __iomem *sar_base;
/*
* Program the wakeup routine address for the CPU0 and CPU1
@@ -135,6 +138,36 @@
__raw_writel(scu_pwr_st, pm_info->scu_sar_addr);
}
+/*
+ * Store the CPU cluster state for L2X0 low power operations.
+ */
+static void l2x0_pwrst_prepare(unsigned int cpu_id, unsigned int save_state)
+{
+ struct omap4_cpu_pm_info *pm_info = &per_cpu(omap4_pm_info, cpu_id);
+
+ __raw_writel(save_state, pm_info->l2x0_sar_addr);
+}
+
+/*
+ * Save the L2X0 AUXCTRL and POR value to SAR memory. Its used to
+ * in every restore MPUSS OFF path.
+ */
+#ifdef CONFIG_CACHE_L2X0
+static void save_l2x0_context(void)
+{
+ u32 val;
+ void __iomem *l2x0_base = omap4_get_l2cache_base();
+
+ val = __raw_readl(l2x0_base + L2X0_AUX_CTRL);
+ __raw_writel(val, sar_base + L2X0_AUXCTRL_OFFSET);
+ val = __raw_readl(l2x0_base + L2X0_PREFETCH_CTRL);
+ __raw_writel(val, sar_base + L2X0_PREFETCH_CTRL_OFFSET);
+}
+#else
+static void save_l2x0_context(void)
+{}
+#endif
+
/**
* omap4_enter_lowpower: OMAP4 MPUSS Low Power Entry Function
* The purpose of this function is to manage low power programming
@@ -182,6 +215,7 @@
set_cpu_next_pwrst(cpu, power_state);
set_cpu_wakeup_addr(cpu, virt_to_phys(omap4_cpu_resume));
scu_pwrst_prepare(cpu, power_state);
+ l2x0_pwrst_prepare(cpu, save_state);
/*
* Call low level function with targeted low power state.
@@ -239,17 +273,19 @@
int __init omap4_mpuss_init(void)
{
struct omap4_cpu_pm_info *pm_info;
- void __iomem *sar_base = omap4_get_sar_ram_base();
if (omap_rev() == OMAP4430_REV_ES1_0) {
WARN(1, "Power Management not supported on OMAP4430 ES1.0\n");
return -ENODEV;
}
+ sar_base = omap4_get_sar_ram_base();
+
/* Initilaise per CPU PM information */
pm_info = &per_cpu(omap4_pm_info, 0x0);
pm_info->scu_sar_addr = sar_base + SCU_OFFSET0;
pm_info->wkup_sar_addr = sar_base + CPU0_WAKEUP_NS_PA_ADDR_OFFSET;
+ pm_info->l2x0_sar_addr = sar_base + L2X0_SAVE_OFFSET0;
pm_info->pwrdm = pwrdm_lookup("cpu0_pwrdm");
if (!pm_info->pwrdm) {
pr_err("Lookup failed for CPU0 pwrdm\n");
@@ -265,6 +301,7 @@
pm_info = &per_cpu(omap4_pm_info, 0x1);
pm_info->scu_sar_addr = sar_base + SCU_OFFSET1;
pm_info->wkup_sar_addr = sar_base + CPU1_WAKEUP_NS_PA_ADDR_OFFSET;
+ pm_info->l2x0_sar_addr = sar_base + L2X0_SAVE_OFFSET1;
pm_info->pwrdm = pwrdm_lookup("cpu1_pwrdm");
if (!pm_info->pwrdm) {
pr_err("Lookup failed for CPU1 pwrdm\n");
@@ -290,6 +327,8 @@
else
__raw_writel(0, sar_base + OMAP_TYPE_OFFSET);
+ save_l2x0_context();
+
return 0;
}