mfd: rts5249: Add support for RTS5250S power saving

Enable power saving for RTS5250S as following steps:
1.Set 0xFE58 to enable clock power management.
2.Check cfg space whether support L1SS or not.
3.If support L1SS, set 0xFF03 to free clkreq.
4.When entering idle status, enable aspm
  and set parameters for L1SS and LTR.
5.Wnen entering run status, disable aspm
  and set parameters for L1SS and LTR.
If entering L1SS mode successfully,
electric current will be below 2mA.

Signed-off-by: Rui Feng <rui_feng@realsil.com.cn>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

3 files changed, 305 insertions, 6 deletions

diff --git a/drivers/mfd/rts5249.c b/drivers/mfd/rts5249.c
index 40f8bb14fc59..7fcf37ba922c 100644
--- a/drivers/mfd/rts5249.c
+++ b/drivers/mfd/rts5249.c
@@ -103,8 +103,64 @@ static void rtsx_base_force_power_down(struct rtsx_pcr *pcr, u8 pm_state)
 	rtsx_pci_write_register(pcr, FPDCTL, 0x03, 0x03);
 }
 
+static void rts5249_init_from_cfg(struct rtsx_pcr *pcr)
+{
+	struct rtsx_cr_option *option = &(pcr->option);
+	u32 lval;
+
+	if (CHK_PCI_PID(pcr, PID_524A))
+		rtsx_pci_read_config_dword(pcr,
+			PCR_ASPM_SETTING_REG1, &lval);
+	else
+		rtsx_pci_read_config_dword(pcr,
+			PCR_ASPM_SETTING_REG2, &lval);
+
+	if (lval & ASPM_L1_1_EN_MASK)
+		rtsx_set_dev_flag(pcr, ASPM_L1_1_EN);
+
+	if (lval & ASPM_L1_2_EN_MASK)
+		rtsx_set_dev_flag(pcr, ASPM_L1_2_EN);
+
+	if (lval & PM_L1_1_EN_MASK)
+		rtsx_set_dev_flag(pcr, PM_L1_1_EN);
+
+	if (lval & PM_L1_2_EN_MASK)
+		rtsx_set_dev_flag(pcr, PM_L1_2_EN);
+
+	if (option->ltr_en) {
+		u16 val;
+
+		pcie_capability_read_word(pcr->pci, PCI_EXP_DEVCTL2, &val);
+		if (val & PCI_EXP_DEVCTL2_LTR_EN) {
+			option->ltr_enabled = true;
+			option->ltr_active = true;
+			rtsx_set_ltr_latency(pcr, option->ltr_active_latency);
+		} else {
+			option->ltr_enabled = false;
+		}
+	}
+}
+
+static int rts5249_init_from_hw(struct rtsx_pcr *pcr)
+{
+	struct rtsx_cr_option *option = &(pcr->option);
+
+	if (rtsx_check_dev_flag(pcr, ASPM_L1_1_EN | ASPM_L1_2_EN
+				| PM_L1_1_EN | PM_L1_2_EN))
+		option->force_clkreq_0 = false;
+	else
+		option->force_clkreq_0 = true;
+
+	return 0;
+}
+
 static int rts5249_extra_init_hw(struct rtsx_pcr *pcr)
 {
+	struct rtsx_cr_option *option = &(pcr->option);
+
+	rts5249_init_from_cfg(pcr);
+	rts5249_init_from_hw(pcr);
+
 	rtsx_pci_init_cmd(pcr);
 
 	/* Rest L1SUB Config */
@@ -125,7 +181,18 @@ static int rts5249_extra_init_hw(struct rtsx_pcr *pcr)
 	else
 		rtsx_pci_add_cmd(pcr, WRITE_REG_CMD, PETXCFG, 0xB0, 0x80);
 
-	return rtsx_pci_send_cmd(pcr, 100);
+	/*
+	 * If u_force_clkreq_0 is enabled, CLKREQ# PIN will be forced
+	 * to drive low, and we forcibly request clock.
+	 */
+	if (option->force_clkreq_0)
+		rtsx_pci_add_cmd(pcr, WRITE_REG_CMD, PETXCFG,
+			FORCE_CLKREQ_DELINK_MASK, FORCE_CLKREQ_LOW);
+	else
+		rtsx_pci_add_cmd(pcr, WRITE_REG_CMD, PETXCFG,
+			FORCE_CLKREQ_DELINK_MASK, FORCE_CLKREQ_HIGH);
+
+	return rtsx_pci_send_cmd(pcr, CMD_TIMEOUT_DEF);
 }
 
 static int rts5249_optimize_phy(struct rtsx_pcr *pcr)
@@ -285,6 +352,31 @@ static int rtsx_base_switch_output_voltage(struct rtsx_pcr *pcr, u8 voltage)
 	return rtsx_pci_send_cmd(pcr, 100);
 }
 
+static void rts5249_set_aspm(struct rtsx_pcr *pcr, bool enable)
+{
+	struct rtsx_cr_option *option = &pcr->option;
+	u8 val = 0;
+
+	if (pcr->aspm_enabled == enable)
+		return;
+
+	if (option->dev_aspm_mode == DEV_ASPM_DYNAMIC) {
+		if (enable)
+			val = pcr->aspm_en;
+		rtsx_pci_update_cfg_byte(pcr,
+			pcr->pcie_cap + PCI_EXP_LNKCTL,
+			ASPM_MASK_NEG, val);
+	} else if (option->dev_aspm_mode == DEV_ASPM_BACKDOOR) {
+		u8 mask = FORCE_ASPM_VAL_MASK | FORCE_ASPM_CTL0;
+
+		if (!enable)
+			val = FORCE_ASPM_CTL0;
+		rtsx_pci_write_register(pcr, ASPM_FORCE_CTL, mask, val);
+	}
+
+	pcr->aspm_enabled = enable;
+}
+
 static const struct pcr_ops rts5249_pcr_ops = {
 	.fetch_vendor_settings = rtsx_base_fetch_vendor_settings,
 	.extra_init_hw = rts5249_extra_init_hw,
@@ -297,6 +389,7 @@ static const struct pcr_ops rts5249_pcr_ops = {
 	.card_power_off = rtsx_base_card_power_off,
 	.switch_output_voltage = rtsx_base_switch_output_voltage,
 	.force_power_down = rtsx_base_force_power_down,
+	.set_aspm = rts5249_set_aspm,
 };
 
 /* SD Pull Control Enable:
@@ -353,6 +446,8 @@ static const u32 rts5249_ms_pull_ctl_disable_tbl[] = {
 
 void rts5249_init_params(struct rtsx_pcr *pcr)
 {
+	struct rtsx_cr_option *option = &(pcr->option);
+
 	pcr->extra_caps = EXTRA_CAPS_SD_SDR50 | EXTRA_CAPS_SD_SDR104;
 	pcr->num_slots = 2;
 	pcr->ops = &rts5249_pcr_ops;
@@ -372,6 +467,20 @@ void rts5249_init_params(struct rtsx_pcr *pcr)
 	pcr->ms_pull_ctl_disable_tbl = rts5249_ms_pull_ctl_disable_tbl;
 
 	pcr->reg_pm_ctrl3 = PM_CTRL3;
+
+	option->dev_flags = (LTR_L1SS_PWR_GATE_CHECK_CARD_EN
+				| LTR_L1SS_PWR_GATE_EN);
+	option->ltr_en = true;
+
+	/* Init latency of active, idle, L1OFF to 60us, 300us, 3ms */
+	option->ltr_active_latency = LTR_ACTIVE_LATENCY_DEF;
+	option->ltr_idle_latency = LTR_IDLE_LATENCY_DEF;
+	option->ltr_l1off_latency = LTR_L1OFF_LATENCY_DEF;
+	option->dev_aspm_mode = DEV_ASPM_DYNAMIC;
+	option->l1_snooze_delay = L1_SNOOZE_DELAY_DEF;
+	option->ltr_l1off_sspwrgate = LTR_L1OFF_SSPWRGATE_5249_DEF;
+	option->ltr_l1off_snooze_sspwrgate =
+		LTR_L1OFF_SNOOZE_SSPWRGATE_5249_DEF;
 }
 
 static int rts524a_write_phy(struct rtsx_pcr *pcr, u8 addr, u16 val)
@@ -459,6 +568,40 @@ static int rts524a_extra_init_hw(struct rtsx_pcr *pcr)
 	return 0;
 }
 
+static void rts5250_set_l1off_cfg_sub_d0(struct rtsx_pcr *pcr, int active)
+{
+	struct rtsx_cr_option *option = &(pcr->option);
+
+	u32 interrupt = rtsx_pci_readl(pcr, RTSX_BIPR);
+	int card_exist = (interrupt & SD_EXIST) | (interrupt & MS_EXIST);
+	int aspm_L1_1, aspm_L1_2;
+	u8 val = 0;
+
+	aspm_L1_1 = rtsx_check_dev_flag(pcr, ASPM_L1_1_EN);
+	aspm_L1_2 = rtsx_check_dev_flag(pcr, ASPM_L1_2_EN);
+
+	if (active) {
+		/* Run, latency: 60us */
+		if (aspm_L1_1)
+			val = option->ltr_l1off_snooze_sspwrgate;
+	} else {
+		/* L1off, latency: 300us */
+		if (aspm_L1_2)
+			val = option->ltr_l1off_sspwrgate;
+	}
+
+	if (aspm_L1_1 || aspm_L1_2) {
+		if (rtsx_check_dev_flag(pcr,
+					LTR_L1SS_PWR_GATE_CHECK_CARD_EN)) {
+			if (card_exist)
+				val &= ~L1OFF_MBIAS2_EN_5250;
+			else
+				val |= L1OFF_MBIAS2_EN_5250;
+		}
+	}
+	rtsx_set_l1off_sub(pcr, val);
+}
+
 static const struct pcr_ops rts524a_pcr_ops = {
 	.write_phy = rts524a_write_phy,
 	.read_phy = rts524a_read_phy,
@@ -473,11 +616,16 @@ static const struct pcr_ops rts524a_pcr_ops = {
 	.card_power_off = rtsx_base_card_power_off,
 	.switch_output_voltage = rtsx_base_switch_output_voltage,
 	.force_power_down = rtsx_base_force_power_down,
+	.set_l1off_cfg_sub_d0 = rts5250_set_l1off_cfg_sub_d0,
+	.set_aspm = rts5249_set_aspm,
 };
 
 void rts524a_init_params(struct rtsx_pcr *pcr)
 {
 	rts5249_init_params(pcr);
+	pcr->option.ltr_l1off_sspwrgate = LTR_L1OFF_SSPWRGATE_5250_DEF;
+	pcr->option.ltr_l1off_snooze_sspwrgate =
+		LTR_L1OFF_SNOOZE_SSPWRGATE_5250_DEF;
 
 	pcr->reg_pm_ctrl3 = RTS524A_PM_CTRL3;
 	pcr->ops = &rts524a_pcr_ops;
@@ -576,11 +724,16 @@ static const struct pcr_ops rts525a_pcr_ops = {
 	.card_power_off = rtsx_base_card_power_off,
 	.switch_output_voltage = rts525a_switch_output_voltage,
 	.force_power_down = rtsx_base_force_power_down,
+	.set_l1off_cfg_sub_d0 = rts5250_set_l1off_cfg_sub_d0,
+	.set_aspm = rts5249_set_aspm,
 };
 
 void rts525a_init_params(struct rtsx_pcr *pcr)
 {
 	rts5249_init_params(pcr);
+	pcr->option.ltr_l1off_sspwrgate = LTR_L1OFF_SSPWRGATE_5250_DEF;
+	pcr->option.ltr_l1off_snooze_sspwrgate =
+		LTR_L1OFF_SNOOZE_SSPWRGATE_5250_DEF;
 
 	pcr->reg_pm_ctrl3 = RTS524A_PM_CTRL3;
 	pcr->ops = &rts525a_pcr_ops;
diff --git a/drivers/mfd/rtsx_pcr.c b/drivers/mfd/rtsx_pcr.c
index 3cf69e5c5703..590fb9aad77d 100644
--- a/drivers/mfd/rtsx_pcr.c
+++ b/drivers/mfd/rtsx_pcr.c
@@ -79,6 +79,96 @@ static inline void rtsx_pci_disable_aspm(struct rtsx_pcr *pcr)
 		0xFC, 0);
 }
 
+int rtsx_comm_set_ltr_latency(struct rtsx_pcr *pcr, u32 latency)
+{
+	rtsx_pci_write_register(pcr, MSGTXDATA0,
+				MASK_8_BIT_DEF, (u8) (latency & 0xFF));
+	rtsx_pci_write_register(pcr, MSGTXDATA1,
+				MASK_8_BIT_DEF, (u8)((latency >> 8) & 0xFF));
+	rtsx_pci_write_register(pcr, MSGTXDATA2,
+				MASK_8_BIT_DEF, (u8)((latency >> 16) & 0xFF));
+	rtsx_pci_write_register(pcr, MSGTXDATA3,
+				MASK_8_BIT_DEF, (u8)((latency >> 24) & 0xFF));
+	rtsx_pci_write_register(pcr, LTR_CTL, LTR_TX_EN_MASK |
+		LTR_LATENCY_MODE_MASK, LTR_TX_EN_1 | LTR_LATENCY_MODE_SW);
+
+	return 0;
+}
+
+int rtsx_set_ltr_latency(struct rtsx_pcr *pcr, u32 latency)
+{
+	if (pcr->ops->set_ltr_latency)
+		return pcr->ops->set_ltr_latency(pcr, latency);
+	else
+		return rtsx_comm_set_ltr_latency(pcr, latency);
+}
+
+static void rtsx_comm_set_aspm(struct rtsx_pcr *pcr, bool enable)
+{
+	struct rtsx_cr_option *option = &pcr->option;
+
+	if (pcr->aspm_enabled == enable)
+		return;
+
+	if (option->dev_aspm_mode == DEV_ASPM_DYNAMIC) {
+		if (enable)
+			rtsx_pci_enable_aspm(pcr);
+		else
+			rtsx_pci_disable_aspm(pcr);
+	} else if (option->dev_aspm_mode == DEV_ASPM_BACKDOOR) {
+		u8 mask = FORCE_ASPM_VAL_MASK;
+		u8 val = 0;
+
+		if (enable)
+			val = pcr->aspm_en;
+		rtsx_pci_write_register(pcr, ASPM_FORCE_CTL,  mask, val);
+	}
+
+	pcr->aspm_enabled = enable;
+}
+
+static void rtsx_disable_aspm(struct rtsx_pcr *pcr)
+{
+	if (pcr->ops->set_aspm)
+		pcr->ops->set_aspm(pcr, false);
+	else
+		rtsx_comm_set_aspm(pcr, false);
+}
+
+int rtsx_set_l1off_sub(struct rtsx_pcr *pcr, u8 val)
+{
+	rtsx_pci_write_register(pcr, L1SUB_CONFIG3, 0xFF, val);
+
+	return 0;
+}
+
+void rtsx_set_l1off_sub_cfg_d0(struct rtsx_pcr *pcr, int active)
+{
+	if (pcr->ops->set_l1off_cfg_sub_d0)
+		pcr->ops->set_l1off_cfg_sub_d0(pcr, active);
+}
+
+static void rtsx_comm_pm_full_on(struct rtsx_pcr *pcr)
+{
+	struct rtsx_cr_option *option = &pcr->option;
+
+	rtsx_disable_aspm(pcr);
+
+	if (option->ltr_enabled)
+		rtsx_set_ltr_latency(pcr, option->ltr_active_latency);
+
+	if (rtsx_check_dev_flag(pcr, LTR_L1SS_PWR_GATE_EN))
+		rtsx_set_l1off_sub_cfg_d0(pcr, 1);
+}
+
+void rtsx_pm_full_on(struct rtsx_pcr *pcr)
+{
+	if (pcr->ops->full_on)
+		pcr->ops->full_on(pcr);
+	else
+		rtsx_comm_pm_full_on(pcr);
+}
+
 void rtsx_pci_start_run(struct rtsx_pcr *pcr)
 {
 	/* If pci device removed, don't queue idle work any more */
@@ -89,9 +179,7 @@ void rtsx_pci_start_run(struct rtsx_pcr *pcr)
 		pcr->state = PDEV_STAT_RUN;
 		if (pcr->ops->enable_auto_blink)
 			pcr->ops->enable_auto_blink(pcr);
-
-		if (pcr->aspm_en)
-			rtsx_pci_disable_aspm(pcr);
+		rtsx_pm_full_on(pcr);
 	}
 
 	mod_delayed_work(system_wq, &pcr->idle_work, msecs_to_jiffies(200));
@@ -958,6 +1046,41 @@ static int rtsx_pci_acquire_irq(struct rtsx_pcr *pcr)
 	return 0;
 }
 
+static void rtsx_enable_aspm(struct rtsx_pcr *pcr)
+{
+	if (pcr->ops->set_aspm)
+		pcr->ops->set_aspm(pcr, true);
+	else
+		rtsx_comm_set_aspm(pcr, true);
+}
+
+static void rtsx_comm_pm_power_saving(struct rtsx_pcr *pcr)
+{
+	struct rtsx_cr_option *option = &pcr->option;
+
+	if (option->ltr_enabled) {
+		u32 latency = option->ltr_l1off_latency;
+
+		if (rtsx_check_dev_flag(pcr, L1_SNOOZE_TEST_EN))
+			mdelay(option->l1_snooze_delay);
+
+		rtsx_set_ltr_latency(pcr, latency);
+	}
+
+	if (rtsx_check_dev_flag(pcr, LTR_L1SS_PWR_GATE_EN))
+		rtsx_set_l1off_sub_cfg_d0(pcr, 0);
+
+	rtsx_enable_aspm(pcr);
+}
+
+void rtsx_pm_power_saving(struct rtsx_pcr *pcr)
+{
+	if (pcr->ops->power_saving)
+		pcr->ops->power_saving(pcr);
+	else
+		rtsx_comm_pm_power_saving(pcr);
+}
+
 static void rtsx_pci_idle_work(struct work_struct *work)
 {
 	struct delayed_work *dwork = to_delayed_work(work);
@@ -974,8 +1097,7 @@ static void rtsx_pci_idle_work(struct work_struct *work)
 	if (pcr->ops->turn_off_led)
 		pcr->ops->turn_off_led(pcr);
 
-	if (pcr->aspm_en)
-		rtsx_pci_enable_aspm(pcr);
+	rtsx_pm_power_saving(pcr);
 
 	mutex_unlock(&pcr->pcr_mutex);
 }
@@ -1063,6 +1185,16 @@ static int rtsx_pci_init_hw(struct rtsx_pcr *pcr)
 	if (err < 0)
 		return err;
 
+	switch (PCI_PID(pcr)) {
+	case PID_5250:
+	case PID_524A:
+	case PID_525A:
+		rtsx_pci_write_register(pcr, PM_CLK_FORCE_CTL, 1, 1);
+		break;
+	default:
+		break;
+	}
+
 	/* Enable clk_request_n to enable clock power management */
 	rtsx_pci_write_config_byte(pcr, pcr->pcie_cap + PCI_EXP_LNKCTL + 1, 1);
 	/* Enter L1 when host tx idle */
diff --git a/drivers/mfd/rtsx_pcr.h b/drivers/mfd/rtsx_pcr.h
index 931d1ae3ce32..ec784e04fe20 100644
--- a/drivers/mfd/rtsx_pcr.h
+++ b/drivers/mfd/rtsx_pcr.h
@@ -32,6 +32,18 @@
 #define RTS524A_PME_FORCE_CTL		0xFF78
 #define RTS524A_PM_CTRL3		0xFF7E
 
+#define LTR_ACTIVE_LATENCY_DEF		0x883C
+#define LTR_IDLE_LATENCY_DEF		0x892C
+#define LTR_L1OFF_LATENCY_DEF		0x9003
+#define L1_SNOOZE_DELAY_DEF		1
+#define LTR_L1OFF_SSPWRGATE_5249_DEF		0xAF
+#define LTR_L1OFF_SSPWRGATE_5250_DEF		0xFF
+#define LTR_L1OFF_SNOOZE_SSPWRGATE_5249_DEF	0xAC
+#define LTR_L1OFF_SNOOZE_SSPWRGATE_5250_DEF	0xF8
+#define CMD_TIMEOUT_DEF		100
+#define ASPM_MASK_NEG		0xFC
+#define MASK_8_BIT_DEF		0xFF
+
 int __rtsx_pci_write_phy_register(struct rtsx_pcr *pcr, u8 addr, u16 val);
 int __rtsx_pci_read_phy_register(struct rtsx_pcr *pcr, u8 addr, u16 *val);
 
@@ -85,5 +97,7 @@ do {									\
 
 /* generic operations */
 int rtsx_gops_pm_reset(struct rtsx_pcr *pcr);
+int rtsx_set_ltr_latency(struct rtsx_pcr *pcr, u32 latency);
+int rtsx_set_l1off_sub(struct rtsx_pcr *pcr, u8 val);
 
 #endif