ARM: imx: add i.MX7ULP cpuidle support

This patch adds cpuidle support for i.MX7ULP, 3 cpuidle
states supported as below:

1. WFI, just ARM wfi;
2. WAIT mode, mapped to SoC's partial stop mode #3;
3. STOP mode, mapped to SoC's partial stop mode #1.

In WAIT mode, system clock and bus clock will be enabled;
In STOP mode, system clock and bus clock will be disabled.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

1 files changed, 44 insertions, 5 deletions

diff --git a/arch/arm/mach-imx/pm-imx7ulp.c b/arch/arm/mach-imx/pm-imx7ulp.c
index cf6a380c2b8d..7b2f7387e662 100644
--- a/arch/arm/mach-imx/pm-imx7ulp.c
+++ b/arch/arm/mach-imx/pm-imx7ulp.c
@@ -9,21 +9,60 @@
 #include <linux/of.h>
 #include <linux/of_address.h>
 
+#include "common.h"
+
 #define SMC_PMCTRL		0x10
 #define BP_PMCTRL_PSTOPO        16
 #define PSTOPO_PSTOP3		0x3
+#define PSTOPO_PSTOP2		0x2
+#define PSTOPO_PSTOP1		0x1
+#define BP_PMCTRL_RUNM		8
+#define RUNM_RUN		0
+#define BP_PMCTRL_STOPM		0
+#define STOPM_STOP		0
+
+#define BM_PMCTRL_PSTOPO	(3 << BP_PMCTRL_PSTOPO)
+#define BM_PMCTRL_RUNM		(3 << BP_PMCTRL_RUNM)
+#define BM_PMCTRL_STOPM		(7 << BP_PMCTRL_STOPM)
+
+static void __iomem *smc1_base;
+
+int imx7ulp_set_lpm(enum ulp_cpu_pwr_mode mode)
+{
+	u32 val = readl_relaxed(smc1_base + SMC_PMCTRL);
+
+	/* clear all */
+	val &= ~(BM_PMCTRL_RUNM | BM_PMCTRL_STOPM | BM_PMCTRL_PSTOPO);
+
+	switch (mode) {
+	case ULP_PM_RUN:
+		/* system/bus clock enabled */
+		val |= PSTOPO_PSTOP3 << BP_PMCTRL_PSTOPO;
+		break;
+	case ULP_PM_WAIT:
+		/* system clock disabled, bus clock enabled */
+		val |= PSTOPO_PSTOP2 << BP_PMCTRL_PSTOPO;
+		break;
+	case ULP_PM_STOP:
+		/* system/bus clock disabled */
+		val |= PSTOPO_PSTOP1 << BP_PMCTRL_PSTOPO;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	writel_relaxed(val, smc1_base + SMC_PMCTRL);
+
+	return 0;
+}
 
 void __init imx7ulp_pm_init(void)
 {
 	struct device_node *np;
-	void __iomem *smc1_base;
 
 	np = of_find_compatible_node(NULL, NULL, "fsl,imx7ulp-smc1");
 	smc1_base = of_iomap(np, 0);
 	WARN_ON(!smc1_base);
 
-	/* Partial Stop mode 3 with system/bus clock enabled */
-	writel_relaxed(PSTOPO_PSTOP3 << BP_PMCTRL_PSTOPO,
-		       smc1_base + SMC_PMCTRL);
-	iounmap(smc1_base);
+	imx7ulp_set_lpm(ULP_PM_RUN);
 }