[PATCH v3 1/3] spi:amd: Add support for latest platform

[Nehal Bakulchandra Shah <Nehal-Bakulchandra.shah@xxxxxxx>]

-Add device ID for new generation of platform.
-Modify spi_busy and opcode commands based on controller version.

Reviewed-by: Shyam Sundar S K <Shyam-sundar.S-k@xxxxxxx>
Reviewed-by: Liang Liang <liang.liang@xxxxxxx>
Signed-off-by: Nehal Bakulchandra Shah <Nehal-Bakulchandra.shah@xxxxxxx>
---
 drivers/spi/spi-amd.c | 72 +++++++++++++++++++++++++++++++++++++------
 1 file changed, 63 insertions(+), 9 deletions(-)

diff --git a/drivers/spi/spi-amd.c b/drivers/spi/spi-amd.c
index 3cf76096a76d..2150f54512d9 100644
--- a/drivers/spi/spi-amd.c
+++ b/drivers/spi/spi-amd.c
@@ -14,10 +14,12 @@
 #include <linux/spi/spi.h>
 
 #define AMD_SPI_CTRL0_REG	0x00
+#define AMD_SPI_OPCODE_REG  0x45
+#define AMD_SPI_CMD_TRIGGER_REG 0x47
 #define AMD_SPI_EXEC_CMD	BIT(16)
 #define AMD_SPI_FIFO_CLEAR	BIT(20)
 #define AMD_SPI_BUSY		BIT(31)
-
+#define AMD_SPI_TRIGGER_CMD	BIT(7)
 #define AMD_SPI_OPCODE_MASK	0xFF
 
 #define AMD_SPI_ALT_CS_REG	0x1D
@@ -34,11 +36,31 @@
 #define AMD_SPI_XFER_TX		1
 #define AMD_SPI_XFER_RX		2
 
+#ifdef CONFIG_ACPI
+struct amd_spi_devtype_data {
+	u32 spi_status;
+	u8	version;
+};
+
+static const struct amd_spi_devtype_data spi_v1 = {
+	.spi_status	= AMD_SPI_CTRL0_REG,
+	.version	= 0,
+};
+
+static const struct amd_spi_devtype_data spi_v2 = {
+	.spi_status	= AMD_SPI_STATUS_REG,
+	.version	= 1,
+};
+#endif
+
 struct amd_spi {
 	void __iomem *io_remap_addr;
 	unsigned long io_base_addr;
 	u32 rom_addr;
 	u8 chip_select;
+	const struct amd_spi_devtype_data *devtype_data;
+	struct spi_device *spi_dev;
+	struct spi_master *master;
 };
 
 static inline u8 amd_spi_readreg8(struct spi_master *master, int idx)
@@ -98,6 +120,14 @@ static void amd_spi_select_chip(struct spi_master *master)
 			      AMD_SPI_ALT_CS_MASK);
 }
 
+static void amd_spi_clear_chip(struct spi_master *master)
+{
+	struct amd_spi *amd_spi = spi_master_get_devdata(master);
+	u8 chip_select = amd_spi->chip_select;
+
+	amd_spi_writereg8(master, AMD_SPI_ALT_CS_REG, chip_select & 0XFC);
+}
+
 static void amd_spi_clear_fifo_ptr(struct spi_master *master)
 {
 	amd_spi_setclear_reg32(master, AMD_SPI_CTRL0_REG, AMD_SPI_FIFO_CLEAR,
@@ -106,8 +136,13 @@ static void amd_spi_clear_fifo_ptr(struct spi_master *master)
 
 static void amd_spi_set_opcode(struct spi_master *master, u8 cmd_opcode)
 {
-	amd_spi_setclear_reg32(master, AMD_SPI_CTRL0_REG, cmd_opcode,
-			       AMD_SPI_OPCODE_MASK);
+	struct amd_spi *amd_spi = spi_master_get_devdata(master);
+
+	if (!amd_spi->devtype_data->version)
+		amd_spi_setclear_reg32(master, AMD_SPI_CTRL0_REG, cmd_opcode,
+				       AMD_SPI_OPCODE_MASK);
+	else
+		amd_spi_writereg8(master, AMD_SPI_OPCODE_REG, cmd_opcode);
 }
 
 static inline void amd_spi_set_rx_count(struct spi_master *master,
@@ -126,17 +161,20 @@ static inline int amd_spi_busy_wait(struct amd_spi *amd_spi)
 {
 	bool spi_busy;
 	int timeout = 100000;
+	u32 status_reg = amd_spi->devtype_data->spi_status;
 
 	/* poll for SPI bus to become idle */
 	spi_busy = (ioread32((u8 __iomem *)amd_spi->io_remap_addr +
-		    AMD_SPI_CTRL0_REG) & AMD_SPI_BUSY) == AMD_SPI_BUSY;
+				status_reg) & AMD_SPI_BUSY) == AMD_SPI_BUSY;
+
 	while (spi_busy) {
 		usleep_range(10, 20);
 		if (timeout-- < 0)
 			return -ETIMEDOUT;
 
+		/* poll for SPI bus to become idle */
 		spi_busy = (ioread32((u8 __iomem *)amd_spi->io_remap_addr +
-			    AMD_SPI_CTRL0_REG) & AMD_SPI_BUSY) == AMD_SPI_BUSY;
+				status_reg) & AMD_SPI_BUSY) == AMD_SPI_BUSY;
 	}
 
 	return 0;
@@ -146,9 +184,16 @@ static void amd_spi_execute_opcode(struct spi_master *master)
 {
 	struct amd_spi *amd_spi = spi_master_get_devdata(master);
 
+	/*Check for busy wait*/
+	amd_spi_busy_wait(amd_spi);
+
 	/* Set ExecuteOpCode bit in the CTRL0 register */
-	amd_spi_setclear_reg32(master, AMD_SPI_CTRL0_REG, AMD_SPI_EXEC_CMD,
-			       AMD_SPI_EXEC_CMD);
+	if (!amd_spi->devtype_data->version)
+		amd_spi_setclear_reg32(master, AMD_SPI_CTRL0_REG, AMD_SPI_EXEC_CMD,
+				       AMD_SPI_EXEC_CMD);
+	else
+		amd_spi_setclear_reg8(master, AMD_SPI_CMD_TRIGGER_REG, AMD_SPI_TRIGGER_CMD,
+				      AMD_SPI_TRIGGER_CMD);
 
 	amd_spi_busy_wait(amd_spi);
 }
@@ -241,7 +286,8 @@ static int amd_spi_master_transfer(struct spi_master *master,
 	 * program the controller.
 	 */
 	amd_spi_fifo_xfer(amd_spi, master, msg);
-
+	if (amd_spi->devtype_data->version)
+		amd_spi_clear_chip(master);
 	return 0;
 }
 
@@ -266,6 +312,11 @@ static int amd_spi_probe(struct platform_device *pdev)
 		dev_err(dev, "error %d ioremap of SPI registers failed\n", err);
 		goto err_free_master;
 	}
+	amd_spi->devtype_data = device_get_match_data(dev);
+	if (!amd_spi->devtype_data) {
+		err = -ENODEV;
+		goto err_free_master;
+	}
 	dev_dbg(dev, "io_remap_address: %p\n", amd_spi->io_remap_addr);
 
 	/* Initialize the spi_master fields */
@@ -293,7 +344,10 @@ static int amd_spi_probe(struct platform_device *pdev)
 
 #ifdef CONFIG_ACPI
 static const struct acpi_device_id spi_acpi_match[] = {
-	{ "AMDI0061", 0 },
+	{ "AMDI0061",
+	.driver_data = (kernel_ulong_t)&spi_v1 },
+	{ "AMDI0062",
+	.driver_data = (kernel_ulong_t)&spi_v2 },
 	{},
 };
 MODULE_DEVICE_TABLE(acpi, spi_acpi_match);
-- 
2.25.1