OMAP3+: VC: add ability for auto transition

Auto transition is an ability on OMAP3+ devices with SmartReflex
capability to be able to automatically command a specific voltage
in reaction to a device/domain wide power state transition. In order
to support this variance in OMAP3 and OMAP4 devices, we provide a
new API to allow SoC specific OMAP PM code to program required
domain transition as they are detected.

Signed-off-by: Nishanth Menon <nm@ti.com>

5 files changed, 125 insertions, 0 deletions

diff --git a/arch/arm/mach-omap2/prm-regbits-44xx.h b/arch/arm/mach-omap2/prm-regbits-44xx.h
index 175412a..d9b8320 100644
--- a/arch/arm/mach-omap2/prm-regbits-44xx.h
+++ b/arch/arm/mach-omap2/prm-regbits-44xx.h
@@ -92,6 +92,10 @@
 #define OMAP4430_AUTO_CTRL_VDD_MPU_L_SHIFT				2
 #define OMAP4430_AUTO_CTRL_VDD_MPU_L_MASK				(0x3 << 2)
 
+/* Used by PRM_VOLTCTRL */
+#define OMAP4430_AUTO_CTRL_VDD_RET_MASK				(1 << 1)
+#define OMAP4430_AUTO_CTRL_VDD_SLEEP_MASK			(1 << 0)
+
 /* Used by PRM_VC_ERRST */
 #define OMAP4430_BYPS_RA_ERR_SHIFT					25
 #define OMAP4430_BYPS_RA_ERR_MASK					(1 << 25)
diff --git a/arch/arm/mach-omap2/vc.c b/arch/arm/mach-omap2/vc.c
index 2cf520d..1b0562a 100644
--- a/arch/arm/mach-omap2/vc.c
+++ b/arch/arm/mach-omap2/vc.c
@@ -132,6 +132,66 @@ int omap_vc_pre_scale(struct voltagedomain *voltdm,
 	return 0;
 }
 
+/**
+ * omap_vc_set_auto_trans() - set auto transition parameters for a domain
+ * @voltdm:	voltage domain we are interested in
+ * @flag:	which state should we program this to
+ */
+int omap_vc_set_auto_trans(struct voltagedomain *voltdm, u8 flag)
+{
+	struct omap_vc_channel *vc;
+	const struct omap_vc_auto_trans *auto_trans;
+	u8 val = OMAP_VC_CHANNEL_AUTO_TRANSITION_UNSUPPORTED;
+
+	if (!voltdm) {
+		pr_err("%s: NULL Voltage domain!\n", __func__);
+		return -ENOENT;
+	}
+	vc = voltdm->vc;
+	if (!vc) {
+		pr_err("%s: NULL VC Voltage domain %s!\n", __func__,
+		       voltdm->name);
+		return -ENOENT;
+	}
+
+	auto_trans = vc->auto_trans;
+	if (!auto_trans) {
+		pr_debug("%s: No auto trans %s!\n", __func__, voltdm->name);
+		return 0;
+	}
+
+	/* Handle value and masks per silicon data */
+	switch (flag) {
+	case OMAP_VC_CHANNEL_AUTO_TRANSITION_DISABLE:
+		val = 0x0;
+		break;
+	case OMAP_VC_CHANNEL_AUTO_TRANSITION_SLEEP:
+		val = auto_trans->sleep_val;
+		break;
+	case OMAP_VC_CHANNEL_AUTO_TRANSITION_RETENTION:
+		val = auto_trans->retention_val;
+		break;
+	case OMAP_VC_CHANNEL_AUTO_TRANSITION_OFF:
+		val = auto_trans->off_val;
+		break;
+	default:
+		pr_err("%s: Voltdm %s invalid flag %d\n", __func__,
+		       voltdm->name, flag);
+		return -EINVAL;
+	}
+
+	if (val == OMAP_VC_CHANNEL_AUTO_TRANSITION_UNSUPPORTED) {
+		pr_err("%s: transition to %d on %s is NOT supported\n",
+		       __func__, flag, voltdm->name);
+		return -EINVAL;
+	}
+
+	/* All ready - set it and move on.. */
+	voltdm->rmw(vc->auto_trans_mask, val << __ffs(vc->auto_trans_mask),
+		    auto_trans->reg);
+	return 0;
+}
+
 void omap_vc_post_scale(struct voltagedomain *voltdm,
 			unsigned long target_volt,
 			u8 target_vsel, u8 current_vsel)
diff --git a/arch/arm/mach-omap2/vc.h b/arch/arm/mach-omap2/vc.h
index cf20f47..fc042e4 100644
--- a/arch/arm/mach-omap2/vc.h
+++ b/arch/arm/mach-omap2/vc.h
@@ -62,6 +62,20 @@ struct omap_vc_common {
 	u8 i2c_mcode_mask;
 };
 
+/**
+ * struct omap_vc_auto_trans - describe the auto transition for the domain
+ * @reg:		register to modify (usually PRM_VOLTCTRL)
+ * @sleep_val:		value to set for enabling sleep transition
+ * @retention_val:	value to set for enabling retention transition
+ * @off_val:		value to set for enabling off transition
+ */
+struct omap_vc_auto_trans {
+	u8 reg;
+	u8 sleep_val;
+	u8 retention_val;
+	u8 off_val;
+};
+
 /* omap_vc_channel.flags values */
 #define OMAP_VC_CHANNEL_DEFAULT BIT(0)
 #define OMAP_VC_CHANNEL_CFG_MUTANT BIT(1)
@@ -72,6 +86,8 @@ struct omap_vc_common {
  * @common: pointer to VC common data for this platform
  * @smps_sa_mask: i2c slave address bitmask in the PRM_VC_SMPS_SA register
  * @smps_volra_mask: VOLRA* bitmask in the PRM_VC_VOL_RA register
+ * @auto_trans: Auto transition information
+ * @auto_trans_mask: Auto transition mask for this channel
  */
 struct omap_vc_channel {
 	u8 flags;
@@ -91,6 +107,9 @@ struct omap_vc_channel {
 	u32 smps_cmdra_mask;
 	u8 cmdval_reg;
 	u8 cfg_channel_sa_shift;
+
+	const struct omap_vc_auto_trans *auto_trans;
+	u32 auto_trans_mask;
 };
 
 extern struct omap_vc_channel omap3_vc_mpu;
@@ -107,6 +126,15 @@ int omap_vc_pre_scale(struct voltagedomain *voltdm,
 void omap_vc_post_scale(struct voltagedomain *voltdm,
 			unsigned long target_volt,
 			u8 target_vsel, u8 current_vsel);
+
+/* Auto transition flags for users */
+#define OMAP_VC_CHANNEL_AUTO_TRANSITION_DISABLE		0
+#define OMAP_VC_CHANNEL_AUTO_TRANSITION_SLEEP		1
+#define OMAP_VC_CHANNEL_AUTO_TRANSITION_RETENTION	2
+#define OMAP_VC_CHANNEL_AUTO_TRANSITION_OFF		3
+/* For silicon data to mark unsupported transition */
+#define OMAP_VC_CHANNEL_AUTO_TRANSITION_UNSUPPORTED	0xff
+int omap_vc_set_auto_trans(struct voltagedomain *voltdm, u8 flag);
 int omap_vc_bypass_scale_voltage(struct voltagedomain *voltdm,
 				 unsigned long target_volt);
 int omap_vc_bypass_send_i2c_msg(struct voltagedomain *voltdm,
diff --git a/arch/arm/mach-omap2/vc3xxx_data.c b/arch/arm/mach-omap2/vc3xxx_data.c
index 95d7701..c21d3f5 100644
--- a/arch/arm/mach-omap2/vc3xxx_data.c
+++ b/arch/arm/mach-omap2/vc3xxx_data.c
@@ -49,6 +49,18 @@ static struct omap_vc_common omap3_vc_common = {
 	.i2c_mcode_mask	 = OMAP3430_MCODE_MASK,
 };
 
+/*
+ * VC auto transition settings for OMAP3. On OMAP3, we just have a single
+ * device wide state that is achieved on core, so we shall use this data
+ * only for core domain transition
+ */
+static const struct omap_vc_auto_trans omap3_vc_auto_trans = {
+	.reg = OMAP3_PRM_VOLTCTRL_OFFSET,
+	.sleep_val =  OMAP3430_AUTO_SLEEP_MASK,
+	.retention_val = OMAP3430_AUTO_RET_MASK,
+	.off_val = OMAP3430_AUTO_OFF_MASK,
+};
+
 struct omap_vc_channel omap3_vc_mpu = {
 	.common = &omap3_vc_common,
 	.cmdval_reg = OMAP3_PRM_VC_CMD_VAL_0_OFFSET,
@@ -65,4 +77,8 @@ struct omap_vc_channel omap3_vc_core = {
 	.smps_volra_mask = OMAP3430_VOLRA1_MASK,
 	.smps_cmdra_mask = OMAP3430_CMDRA1_MASK,
 	.cfg_channel_sa_shift = OMAP3430_PRM_VC_SMPS_SA_SA1_SHIFT,
+
+	.auto_trans = &omap3_vc_auto_trans,
+	.auto_trans_mask = OMAP3430_AUTO_OFF_MASK | OMAP3430_AUTO_RET_MASK |
+				OMAP3430_AUTO_SLEEP_MASK,
 };
diff --git a/arch/arm/mach-omap2/vc44xx_data.c b/arch/arm/mach-omap2/vc44xx_data.c
index 0a4fc37..3757d4f 100644
--- a/arch/arm/mach-omap2/vc44xx_data.c
+++ b/arch/arm/mach-omap2/vc44xx_data.c
@@ -50,6 +50,14 @@ static const struct omap_vc_common omap4_vc_common = {
 	.i2c_mcode_mask	 = OMAP4430_HSMCODE_MASK,
 };
 
+/* VC auto transition settings for OMAP4. */
+static const struct omap_vc_auto_trans omap4_vc_auto_trans = {
+	.reg = OMAP4_PRM_VOLTCTRL_OFFSET,
+	.sleep_val = OMAP4430_AUTO_CTRL_VDD_SLEEP_MASK,
+	.retention_val = OMAP4430_AUTO_CTRL_VDD_RET_MASK,
+	.off_val = OMAP_VC_CHANNEL_AUTO_TRANSITION_UNSUPPORTED,
+};
+
 /* VC instance data for each controllable voltage line */
 struct omap_vc_channel omap4_vc_mpu = {
 	.flags = OMAP_VC_CHANNEL_DEFAULT | OMAP_VC_CHANNEL_CFG_MUTANT,
@@ -59,6 +67,9 @@ struct omap_vc_channel omap4_vc_mpu = {
 	.smps_volra_mask = OMAP4430_VOLRA_VDD_MPU_L_MASK,
 	.smps_cmdra_mask = OMAP4430_CMDRA_VDD_MPU_L_MASK,
 	.cfg_channel_sa_shift = OMAP4430_SA_VDD_MPU_L_SHIFT,
+
+	.auto_trans = &omap4_vc_auto_trans,
+	.auto_trans_mask = OMAP4430_AUTO_CTRL_VDD_MPU_L_MASK,
 };
 
 struct omap_vc_channel omap4_vc_iva = {
@@ -68,6 +79,9 @@ struct omap_vc_channel omap4_vc_iva = {
 	.smps_volra_mask = OMAP4430_VOLRA_VDD_IVA_L_MASK,
 	.smps_cmdra_mask = OMAP4430_CMDRA_VDD_IVA_L_MASK,
 	.cfg_channel_sa_shift = OMAP4430_SA_VDD_IVA_L_SHIFT,
+
+	.auto_trans = &omap4_vc_auto_trans,
+	.auto_trans_mask = OMAP4430_AUTO_CTRL_VDD_IVA_L_MASK,
 };
 
 struct omap_vc_channel omap4_vc_core = {
@@ -77,5 +91,8 @@ struct omap_vc_channel omap4_vc_core = {
 	.smps_volra_mask = OMAP4430_VOLRA_VDD_CORE_L_MASK,
 	.smps_cmdra_mask = OMAP4430_CMDRA_VDD_CORE_L_MASK,
 	.cfg_channel_sa_shift = OMAP4430_SA_VDD_CORE_L_SHIFT,
+
+	.auto_trans = &omap4_vc_auto_trans,
+	.auto_trans_mask = OMAP4430_AUTO_CTRL_VDD_CORE_L_MASK,
 };