xilinx: versal2: Clean UFS firmware interface

The M-PHY and SRAM readiness poll loops move out of the UFS controller
driver and into the firmware backend, exposed as blocking waits with
a caller-owned timeout budget. This keeps the UFS driver backend-agnostic
and lets an other backends offload the wait to the platform in a single
call instead of round-tripping every poll.

set_sram_bypass() now performs the SRAM_CSR read-modify-write in the
firmware layer.

Hook up functions are also update to reflect their usage.

Signed-off-by: Michal Simek <[email protected]>
Link: https://patch.msgid.link/26bc9aa2c02921690e126ab3401f7974ef04ad6e.1785394153.git.michal.simek@amd.com

5 files changed, 95 insertions, 97 deletions

diff --git a/arch/arm/mach-versal2/cpu.c b/arch/arm/mach-versal2/cpu.c
index 01efa7b7928..d72f66f4fba 100644
--- a/arch/arm/mach-versal2/cpu.c
+++ b/arch/arm/mach-versal2/cpu.c
@@ -11,6 +11,7 @@
 #include <malloc.h>
 #include <time.h>
 #include <vsprintf.h>
+#include <wait_bit.h>
 #include <asm/armv8/mmu.h>
 #include <asm/cache.h>
 #include <asm/global_data.h>
@@ -160,25 +161,40 @@ u8 __weak versal2_get_bootmode(void)
 	return bootmode;
 }
 
-int __weak zynqmp_pm_ufs_get_txrx_cfgrdy(u32 *value)
+/*
+ * Wait for the M-PHY TX/RX config-ready status to settle (all bits cleared) or
+ * @timeout_us to elapse. The direct-MMIO fallback owns the poll loop, mirroring
+ * the EEMI backend; the timeout budget is owned by the caller.
+ */
+int __weak zynqmp_pm_wait_mphy_tx_rx_config_ready(u32 timeout_us)
 {
-	*value = readl(PMXC_SLCR_BASE_ADDRESS + PMXC_TX_RX_CFG_RDY);
-	return 0;
+	return wait_for_bit_le32((void *)(uintptr_t)(PMXC_SLCR_BASE_ADDRESS +
+						     PMXC_TX_RX_CFG_RDY),
+				 TX_RX_CFG_RDY_MASK, false, timeout_us / 1000,
+				 false);
 }
 
-int __weak zynqmp_pm_ufs_sram_csr_read(u32 *value)
+int __weak zynqmp_pm_wait_sram_init_done(u32 timeout_us)
 {
-	*value = readl(PMXC_SLCR_BASE_ADDRESS + PMXC_SRAM_CSR);
-	return 0;
+	return wait_for_bit_le32((void *)(uintptr_t)(PMXC_SLCR_BASE_ADDRESS +
+						     PMXC_SRAM_CSR),
+				 SRAM_CSR_INIT_DONE_MASK, true, timeout_us / 1000,
+				 false);
 }
 
-int __weak zynqmp_pm_ufs_sram_csr_write(u32 *value)
+int __weak zynqmp_pm_set_sram_bypass(void)
 {
-	writel(*value, PMXC_SLCR_BASE_ADDRESS + PMXC_SRAM_CSR);
+	u32 sram_csr;
+
+	sram_csr = readl(PMXC_SLCR_BASE_ADDRESS + PMXC_SRAM_CSR);
+	sram_csr &= ~SRAM_CSR_EXT_LD_DONE_MASK;
+	sram_csr |= SRAM_CSR_BYPASS_MASK;
+	writel(sram_csr, PMXC_SLCR_BASE_ADDRESS + PMXC_SRAM_CSR);
+
 	return 0;
 }
 
-int __weak zynqmp_pm_ufs_cal_reg(u32 *value)
+int __weak zynqmp_pm_get_ufs_calibration_values(u32 *value)
 {
 	*value = readl(PMXC_EFUSE_CACHE_BASE_ADDRESS + PMXC_UFS_CAL_1_OFFSET);
 	return 0;
diff --git a/arch/arm/mach-versal2/include/mach/hardware.h b/arch/arm/mach-versal2/include/mach/hardware.h
index 7977529fd6c..4ff732d660f 100644
--- a/arch/arm/mach-versal2/include/mach/hardware.h
+++ b/arch/arm/mach-versal2/include/mach/hardware.h
@@ -65,6 +65,11 @@
 #define PMXC_SRAM_CSR			0x4C
 #define PMXC_TX_RX_CFG_RDY		0x54
 
+#define SRAM_CSR_INIT_DONE_MASK		BIT(0)
+#define SRAM_CSR_EXT_LD_DONE_MASK	BIT(1)
+#define SRAM_CSR_BYPASS_MASK		BIT(2)
+#define TX_RX_CFG_RDY_MASK		GENMASK(3, 0)
+
 #define PMC_GLOBAL_PGGS3_REG	0xF111005C
 #define PMC_GLOBAL_PGGS4_REG	0xF1110060
 
diff --git a/arch/arm/mach-versal2/include/mach/sys_proto.h b/arch/arm/mach-versal2/include/mach/sys_proto.h
index c1dfd184d86..d678adf9c26 100644
--- a/arch/arm/mach-versal2/include/mach/sys_proto.h
+++ b/arch/arm/mach-versal2/include/mach/sys_proto.h
@@ -22,9 +22,9 @@ u8 versal2_get_bootmode(void);
 /* EL3 clock/timer register setup, called from board_early_init_r() */
 void versal2_timer_setup(void);
 
-int zynqmp_pm_ufs_get_txrx_cfgrdy(u32 *value);
-int zynqmp_pm_ufs_sram_csr_read(u32 *value);
-int zynqmp_pm_ufs_sram_csr_write(u32 *value);
-int zynqmp_pm_ufs_cal_reg(u32 *value);
+int zynqmp_pm_wait_mphy_tx_rx_config_ready(u32 timeout_us);
+int zynqmp_pm_wait_sram_init_done(u32 timeout_us);
+int zynqmp_pm_set_sram_bypass(void);
+int zynqmp_pm_get_ufs_calibration_values(u32 *value);
 
 #endif /* _ASM_ARCH_SYS_PROTO_H */
diff --git a/drivers/firmware/firmware-zynqmp.c b/drivers/firmware/firmware-zynqmp.c
index 2bdb1c4d9f8..fae66ccb3d8 100644
--- a/drivers/firmware/firmware-zynqmp.c
+++ b/drivers/firmware/firmware-zynqmp.c
@@ -19,6 +19,7 @@
 #include <asm/ptrace.h>
 #include <asm/system.h>
 #include <linux/bitfield.h>
+#include <linux/delay.h>
 
 #if defined(CONFIG_ZYNQMP_IPI)
 #include <mailbox.h>
@@ -175,51 +176,60 @@ unsigned int zynqmp_firmware_version(void)
 };
 
 #if defined(CONFIG_ARCH_VERSAL2)
-int zynqmp_pm_ufs_get_txrx_cfgrdy(u32 *value)
+/*
+ * Poll the M-PHY TX/RX config-ready status until it settles or @timeout_us
+ * elapses. Legacy EEMI firmware only offers the per-read status primitive, so
+ * the poll loop lives here rather than in the UFS driver; the timeout budget is
+ * owned by the caller.
+ */
+int zynqmp_pm_wait_mphy_tx_rx_config_ready(u32 timeout_us)
 {
 	u32 ret_payload[PAYLOAD_ARG_CNT];
 	int ret;
 
-	if (!value)
-		return -EINVAL;
+	while (timeout_us--) {
+		ret = xilinx_pm_request(PM_IOCTL, PM_REGNODE_PMC_IOU_SLCR,
+					IOCTL_READ_REG, TXRX_CFGRDY_OFFSET, 0, 0,
+					0, ret_payload);
+		if (ret)
+			return ret;
 
-	ret = xilinx_pm_request(PM_IOCTL, PM_REGNODE_PMC_IOU_SLCR,
-				IOCTL_READ_REG, TXRX_CFGRDY_OFFSET, 0, 0,
-				0, ret_payload);
-	if (ret)
-		return ret;
+		if (!(ret_payload[1] & TX_RX_CFG_RDY_MASK))
+			return 0;
 
-	*value = ret_payload[1];
+		udelay(1);
+	}
 
-	return ret;
+	return -ETIMEDOUT;
 }
 
-int zynqmp_pm_ufs_sram_csr_read(u32 *value)
+int zynqmp_pm_wait_sram_init_done(u32 timeout_us)
 {
 	u32 ret_payload[PAYLOAD_ARG_CNT];
 	int ret;
 
-	if (!value)
-		return -EINVAL;
+	while (timeout_us--) {
+		ret = xilinx_pm_request(PM_IOCTL, PM_REGNODE_PMC_IOU_SLCR,
+					IOCTL_READ_REG, SRAM_CSR_OFFSET, 0, 0,
+					0, ret_payload);
+		if (ret)
+			return ret;
 
-	ret = xilinx_pm_request(PM_IOCTL, PM_REGNODE_PMC_IOU_SLCR,
-				IOCTL_READ_REG, SRAM_CSR_OFFSET, 0, 0,
-				0, ret_payload);
-	if (ret)
-		return ret;
+		if (ret_payload[1] & SRAM_CSR_INIT_DONE_MASK)
+			return 0;
 
-	*value = ret_payload[1];
+		udelay(1);
+	}
 
-	return ret;
+	return -ETIMEDOUT;
 }
 
-int zynqmp_pm_ufs_sram_csr_write(u32 *value)
+int zynqmp_pm_set_sram_bypass(void)
 {
+	u32 ret_payload[PAYLOAD_ARG_CNT];
+	u32 sram_csr;
 	int ret;
 
-	if (!value)
-		return -EINVAL;
-
 	ret = zynqmp_pm_is_function_supported(PM_IOCTL, IOCTL_MASK_WRITE_REG);
 	if (ret) {
 		printf("%s: IOCTL_MASK_WRITE_REG is not supported : %d\n"
@@ -228,15 +238,21 @@ int zynqmp_pm_ufs_sram_csr_write(u32 *value)
 	}
 
 	ret = xilinx_pm_request(PM_IOCTL, PM_REGNODE_PMC_IOU_SLCR,
-				IOCTL_MASK_WRITE_REG, SRAM_CSR_OFFSET,
-				GENMASK(2, 1), *value, 0, NULL);
+				IOCTL_READ_REG, SRAM_CSR_OFFSET, 0, 0,
+				0, ret_payload);
 	if (ret)
 		return ret;
 
-	return ret;
+	sram_csr = ret_payload[1];
+	sram_csr &= ~SRAM_CSR_EXT_LD_DONE_MASK;
+	sram_csr |= SRAM_CSR_BYPASS_MASK;
+
+	return xilinx_pm_request(PM_IOCTL, PM_REGNODE_PMC_IOU_SLCR,
+				 IOCTL_MASK_WRITE_REG, SRAM_CSR_OFFSET,
+				 GENMASK(2, 1), sram_csr, 0, NULL);
 }
 
-int zynqmp_pm_ufs_cal_reg(u32 *value)
+int zynqmp_pm_get_ufs_calibration_values(u32 *value)
 {
 	u32 ret_payload[PAYLOAD_ARG_CNT];
 	int ret;
diff --git a/drivers/ufs/ufs-amd-versal2.c b/drivers/ufs/ufs-amd-versal2.c
index 986147848bd..48854792cbf 100644
--- a/drivers/ufs/ufs-amd-versal2.c
+++ b/drivers/ufs/ufs-amd-versal2.c
@@ -20,10 +20,6 @@
 #include "ufshcd-dwc.h"
 #include "ufshci-dwc.h"
 
-#define SRAM_CSR_INIT_DONE_MASK		BIT(0)
-#define SRAM_CSR_EXT_LD_DONE_MASK	BIT(1)
-#define SRAM_CSR_BYPASS_MASK		BIT(2)
-
 #define MPHY_FAST_RX_AFE_CAL		BIT(2)
 #define MPHY_FW_CALIB_CFG_VAL		BIT(8)
 
@@ -31,8 +27,6 @@
 #define MPHY_RX_OVRD_VAL		BIT(2)
 #define MPHY_RX_ACK_MASK		BIT(0)
 
-#define TX_RX_CFG_RDY_MASK		GENMASK(3, 0)
-
 #define TIMEOUT_MICROSEC		1000000L
 
 struct ufs_versal2_priv {
@@ -229,7 +223,6 @@ static int ufs_versal2_setup_phy(struct ufs_hba *hba)
 static int ufs_versal2_phy_init(struct ufs_hba *hba)
 {
 	struct ufs_versal2_priv *priv = dev_get_priv(hba->dev);
-	u32 reg, time_left;
 	int ret;
 	static const struct ufshcd_dme_attr_val rmmi_attrs[] = {
 		{ UIC_ARG_MIB(CBREFCLKCTRL2), CBREFREFCLK_GATE_OVR_EN, DME_LOCAL },
@@ -238,24 +231,15 @@ static int ufs_versal2_phy_init(struct ufs_hba *hba)
 		{ UIC_ARG_MIB(VS_MPHYCFGUPDT), 1, DME_LOCAL }
 	};
 
-	/* Wait for Tx/Rx config_rdy */
-	time_left = TIMEOUT_MICROSEC;
-	do {
-		time_left--;
-		ret = zynqmp_pm_ufs_get_txrx_cfgrdy(&reg);
-		if (ret)
-			return ret;
-
-		reg &= TX_RX_CFG_RDY_MASK;
-		if (!reg)
-			break;
-
-		mdelay(5);
-	} while (time_left);
-
-	if (!time_left) {
+	/*
+	 * Wait for Tx/Rx config_rdy. The poll loop lives in the firmware
+	 * backend (IO, EEMI or SCMI) so this driver stays backend-agnostic;
+	 * the timeout budget stays here with the consumer.
+	 */
+	ret = zynqmp_pm_wait_mphy_tx_rx_config_ready(TIMEOUT_MICROSEC);
+	if (ret) {
 		dev_err(hba->dev, "Tx/Rx configuration signal busy.\n");
-		return -ETIMEDOUT;
+		return ret;
 	}
 
 	ret = ufshcd_dwc_dme_set_attrs(hba, rmmi_attrs, ARRAY_SIZE(rmmi_attrs));
@@ -269,24 +253,11 @@ static int ufs_versal2_phy_init(struct ufs_hba *hba)
 		return ret;
 	}
 
-	/* Wait for SRAM init done */
-	time_left = TIMEOUT_MICROSEC;
-	do {
-		time_left--;
-		ret = zynqmp_pm_ufs_sram_csr_read(&reg);
-		if (ret)
-			return ret;
-
-		reg &= SRAM_CSR_INIT_DONE_MASK;
-		if (reg)
-			break;
-
-		mdelay(5);
-	} while (time_left);
-
-	if (!time_left) {
+	/* Wait for SRAM init done (poll handled by the firmware backend). */
+	ret = zynqmp_pm_wait_sram_init_done(TIMEOUT_MICROSEC);
+	if (ret) {
 		dev_err(hba->dev, "SRAM initialization failed.\n");
-		return -ETIMEDOUT;
+		return ret;
 	}
 
 	ret = ufs_versal2_setup_phy(hba);
@@ -301,7 +272,7 @@ static int ufs_versal2_init(struct ufs_hba *hba)
 	struct ufs_versal2_priv *priv = dev_get_priv(hba->dev);
 	struct clk clk;
 	unsigned long core_clk_rate = 0;
-	u32 cal, sram_csr;
+	u32 cal;
 	int ret = 0;
 
 	priv->phy_mode = UFSHCD_DWC_PHY_MODE_ROM;
@@ -345,28 +316,18 @@ static int ufs_versal2_init(struct ufs_hba *hba)
 		return ret;
 	}
 
-	ret = zynqmp_pm_ufs_sram_csr_read(&sram_csr);
-	if (ret)
+	ret = zynqmp_pm_set_sram_bypass();
+	if (ret) {
+		dev_err(hba->dev, "Bypass SRAM interface failed, err = %d\n", ret);
 		return ret;
-
-	if (!priv->phy_mode) {
-		sram_csr &= ~SRAM_CSR_EXT_LD_DONE_MASK;
-		sram_csr |= SRAM_CSR_BYPASS_MASK;
-	} else {
-		dev_err(hba->dev, "Invalid phy-mode %d.\n", priv->phy_mode);
-		return -EINVAL;
 	}
 
-	ret = zynqmp_pm_ufs_sram_csr_write(&sram_csr);
-	if (ret)
-		return ret;
-
 	/* De Assert RST_UFS Reset for UFS block in PMX_IOU */
 	ret = reset_deassert(priv->rstc);
 	if (ret)
 		dev_err(hba->dev, "host reset deassert failed, err = %d\n", ret);
 
-	ret = zynqmp_pm_ufs_cal_reg(&cal);
+	ret = zynqmp_pm_get_ufs_calibration_values(&cal);
 	if (ret)
 		return ret;