[PATCH 1/3] spi: cadence-quadspi: Add support for PHY module and DQS

[Sai Krishna Potthuri]

Cadence Octal SPI Flash Controller has PHY module, which is used for
handling SPI transactions when there is a requirement for high
performance. Also, this controller supports DQS(data strobe) used for
data capturing in PHY mode rather than internally generated ref_clk.
Xilinx Versal Octal SPI use PHY module and DQS signal when operating in
DTR protocol.

Signed-off-by: Sai Krishna Potthuri <sai.krishna.potthuri at amd.com>
---
 drivers/spi/spi-cadence-quadspi.c | 25 ++++++++++++++++++++++++-
 1 file changed, 24 insertions(+), 1 deletion(-)

diff --git a/drivers/spi/spi-cadence-quadspi.c b/drivers/spi/spi-cadence-quadspi.c
index 676313e1bdad..b55b763003f0 100644
--- a/drivers/spi/spi-cadence-quadspi.c
+++ b/drivers/spi/spi-cadence-quadspi.c
@@ -40,6 +40,8 @@
 #define CQSPI_SUPPORT_EXTERNAL_DMA	BIT(2)
 #define CQSPI_NO_SUPPORT_WR_COMPLETION	BIT(3)
 #define CQSPI_SLOW_SRAM		BIT(4)
+#define CQSPI_HAS_PHY			BIT(5)
+#define CQSPI_HAS_DQS			BIT(6)
 
 /* Capabilities */
 #define CQSPI_SUPPORTS_OCTAL		BIT(0)
@@ -89,6 +91,8 @@ struct cqspi_st {
 	u32			pd_dev_id;
 	bool			wr_completion;
 	bool			slow_sram;
+	bool			use_phy;
+	bool			use_dqs;
 };
 
 struct cqspi_driver_platdata {
@@ -112,6 +116,7 @@ struct cqspi_driver_platdata {
 /* Register map */
 #define CQSPI_REG_CONFIG			0x00
 #define CQSPI_REG_CONFIG_ENABLE_MASK		BIT(0)
+#define CQSPI_REG_CONFIG_PHY_MODE		BIT(3)
 #define CQSPI_REG_CONFIG_ENB_DIR_ACC_CTRL	BIT(7)
 #define CQSPI_REG_CONFIG_DECODE_MASK		BIT(9)
 #define CQSPI_REG_CONFIG_CHIPSELECT_LSB		10
@@ -151,6 +156,7 @@ struct cqspi_driver_platdata {
 #define CQSPI_REG_DELAY_TSHSL_MASK		0xFF
 
 #define CQSPI_REG_READCAPTURE			0x10
+#define CQSPI_REG_READCAPTURE_DQS		BIT(8)
 #define CQSPI_REG_READCAPTURE_BYPASS_LSB	0
 #define CQSPI_REG_READCAPTURE_DELAY_LSB		1
 #define CQSPI_REG_READCAPTURE_DELAY_MASK	0xF
@@ -468,6 +474,8 @@ static int cqspi_enable_dtr(struct cqspi_flash_pdata *f_pdata,
 	if (op->cmd.dtr) {
 		reg |= CQSPI_REG_CONFIG_DTR_PROTO;
 		reg |= CQSPI_REG_CONFIG_DUAL_OPCODE;
+		if (cqspi->use_phy)
+			reg |= CQSPI_REG_CONFIG_PHY_MODE;
 
 		/* Set up command opcode extension. */
 		ret = cqspi_setup_opcode_ext(f_pdata, op, shift);
@@ -476,10 +484,20 @@ static int cqspi_enable_dtr(struct cqspi_flash_pdata *f_pdata,
 	} else {
 		reg &= ~CQSPI_REG_CONFIG_DTR_PROTO;
 		reg &= ~CQSPI_REG_CONFIG_DUAL_OPCODE;
+		reg &= ~CQSPI_REG_CONFIG_PHY_MODE;
 	}
 
 	writel(reg, reg_base + CQSPI_REG_CONFIG);
 
+	reg = readl(reg_base + CQSPI_REG_READCAPTURE);
+
+	if (op->cmd.dtr)
+		reg |= CQSPI_REG_READCAPTURE_DQS;
+	else
+		reg &= ~CQSPI_REG_READCAPTURE_DQS;
+
+	writel(reg, reg_base + CQSPI_REG_READCAPTURE);
+
 	return cqspi_wait_idle(cqspi);
 }
 
@@ -1700,6 +1718,10 @@ static int cqspi_probe(struct platform_device *pdev)
 			cqspi->wr_completion = false;
 		if (ddata->quirks & CQSPI_SLOW_SRAM)
 			cqspi->slow_sram = true;
+		if (ddata->quirks & CQSPI_HAS_PHY)
+			cqspi->use_phy = true;
+		if (ddata->quirks & CQSPI_HAS_DQS)
+			cqspi->use_dqs = true;
 
 		if (of_device_is_compatible(pdev->dev.of_node,
 					    "xlnx,versal-ospi-1.0"))
@@ -1820,7 +1842,8 @@ static const struct cqspi_driver_platdata socfpga_qspi = {
 
 static const struct cqspi_driver_platdata versal_ospi = {
 	.hwcaps_mask = CQSPI_SUPPORTS_OCTAL,
-	.quirks = CQSPI_DISABLE_DAC_MODE | CQSPI_SUPPORT_EXTERNAL_DMA,
+	.quirks = CQSPI_DISABLE_DAC_MODE | CQSPI_SUPPORT_EXTERNAL_DMA
+			| CQSPI_HAS_PHY | CQSPI_HAS_DQS,
 	.indirect_read_dma = cqspi_versal_indirect_read_dma,
 	.get_dma_status = cqspi_get_versal_dma_status,
 };
-- 
2.25.1