Merge series "Add IRQ mode support for hisi-sfc-v3xx driver and some cleanups"...

Merge series "Add IRQ mode support for hisi-sfc-v3xx driver and some cleanups" from Yicong Yang <yangyicong@hisilicon.com>:

This series mainly add the IRQ mode support for hisi-sfc-v3xx driver, and some
cleanups for the preparation of the IRQ mode.
After this patch, the device can work in IRQ mode, or if firmware doesn't
declare irq support it will fall back to Poll mode.

Patch 1-2 refactor the .exec_op() path to make it simpler and clearer.
Patch 3 factor the definition of the interrupt bits.
Patch 4 add the IRQ support of the driver.

Yicong Yang (4):
  spi: hisi-sfc-v3xx: factor out IO modes configuration
  spi: hisi-sfc-v3xx: factor out bus config and transfer functions
  spi: hisi-sfc-v3xx: factor out the bit definition of interrupt
    register
  spi: hisi-sfc-v3xx: add support for IRQ mode

 drivers/spi/spi-hisi-sfc-v3xx.c | 261 +++++++++++++++++++++++++++++-----------
 1 file changed, 190 insertions(+), 71 deletions(-)

--
2.8.1

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drivers/spi/spi-hisi-sfc-v3xx.c

@@ -7,7 +7,9 @@
 
 #include <linux/acpi.h>
 #include <linux/bitops.h>
+#include <linux/completion.h>
 #include <linux/dmi.h>
+#include <linux/interrupt.h>
 #include <linux/iopoll.h>
 #include <linux/module.h>
 #include <linux/platform_device.h>
@@ -17,18 +19,11 @@
 
 #define HISI_SFC_V3XX_VERSION (0x1f8)
 
-#define HISI_SFC_V3XX_INT_STAT (0x120)
-#define HISI_SFC_V3XX_INT_STAT_PP_ERR BIT(2)
-#define HISI_SFC_V3XX_INT_STAT_ADDR_IACCES BIT(5)
+#define HISI_SFC_V3XX_RAW_INT_STAT (0x120)
+#define HISI_SFC_V3XX_INT_STAT (0x124)
+#define HISI_SFC_V3XX_INT_MASK (0x128)
 #define HISI_SFC_V3XX_INT_CLR (0x12c)
-#define HISI_SFC_V3XX_INT_CLR_CLEAR (0xff)
 #define HISI_SFC_V3XX_CMD_CFG (0x300)
-#define HISI_SFC_V3XX_CMD_CFG_DUAL_IN_DUAL_OUT (1 << 17)
-#define HISI_SFC_V3XX_CMD_CFG_DUAL_IO (2 << 17)
-#define HISI_SFC_V3XX_CMD_CFG_FULL_DIO (3 << 17)
-#define HISI_SFC_V3XX_CMD_CFG_QUAD_IN_QUAD_OUT (5 << 17)
-#define HISI_SFC_V3XX_CMD_CFG_QUAD_IO (6 << 17)
-#define HISI_SFC_V3XX_CMD_CFG_FULL_QIO (7 << 17)
 #define HISI_SFC_V3XX_CMD_CFG_DATA_CNT_OFF 9
 #define HISI_SFC_V3XX_CMD_CFG_RW_MSK BIT(8)
 #define HISI_SFC_V3XX_CMD_CFG_DATA_EN_MSK BIT(7)
@@ -40,12 +35,99 @@
 #define HISI_SFC_V3XX_CMD_ADDR (0x30c)
 #define HISI_SFC_V3XX_CMD_DATABUF0 (0x400)
 
+/* Common definition of interrupt bit masks */
+#define HISI_SFC_V3XX_INT_MASK_ALL (0x1ff)	/* all the masks */
+#define HISI_SFC_V3XX_INT_MASK_CPLT BIT(0)	/* command execution complete */
+#define HISI_SFC_V3XX_INT_MASK_PP_ERR BIT(2)	/* page progrom error */
+#define HISI_SFC_V3XX_INT_MASK_IACCES BIT(5)	/* error visiting inaccessible/
+						 * protected address
+						 */
+
+/* IO Mode definition in HISI_SFC_V3XX_CMD_CFG */
+#define HISI_SFC_V3XX_STD (0 << 17)
+#define HISI_SFC_V3XX_DIDO (1 << 17)
+#define HISI_SFC_V3XX_DIO (2 << 17)
+#define HISI_SFC_V3XX_FULL_DIO (3 << 17)
+#define HISI_SFC_V3XX_QIQO (5 << 17)
+#define HISI_SFC_V3XX_QIO (6 << 17)
+#define HISI_SFC_V3XX_FULL_QIO (7 << 17)
+
+/*
+ * The IO modes lookup table. hisi_sfc_v3xx_io_modes[(z - 1) / 2][y / 2][x / 2]
+ * stands for x-y-z mode, as described in SFDP terminology. -EIO indicates
+ * an invalid mode.
+ */
+static const int hisi_sfc_v3xx_io_modes[2][3][3] = {
+	{
+		{ HISI_SFC_V3XX_DIDO, HISI_SFC_V3XX_DIDO, HISI_SFC_V3XX_DIDO },
+		{ HISI_SFC_V3XX_DIO, HISI_SFC_V3XX_FULL_DIO, -EIO },
+		{ -EIO, -EIO, -EIO },
+	},
+	{
+		{ HISI_SFC_V3XX_QIQO, HISI_SFC_V3XX_QIQO, HISI_SFC_V3XX_QIQO },
+		{ -EIO, -EIO, -EIO },
+		{ HISI_SFC_V3XX_QIO, -EIO, HISI_SFC_V3XX_FULL_QIO },
+	},
+};
+
 struct hisi_sfc_v3xx_host {
 	struct device *dev;
 	void __iomem *regbase;
 	int max_cmd_dword;
+	struct completion *completion;
+	int irq;
 };
 
+static void hisi_sfc_v3xx_disable_int(struct hisi_sfc_v3xx_host *host)
+{
+	writel(0, host->regbase + HISI_SFC_V3XX_INT_MASK);
+}
+
+static void hisi_sfc_v3xx_enable_int(struct hisi_sfc_v3xx_host *host)
+{
+	writel(HISI_SFC_V3XX_INT_MASK_ALL, host->regbase + HISI_SFC_V3XX_INT_MASK);
+}
+
+static void hisi_sfc_v3xx_clear_int(struct hisi_sfc_v3xx_host *host)
+{
+	writel(HISI_SFC_V3XX_INT_MASK_ALL, host->regbase + HISI_SFC_V3XX_INT_CLR);
+}
+
+/*
+ * The interrupt status register indicates whether an error occurs
+ * after per operation. Check it, and clear the interrupts for
+ * next time judgement.
+ */
+static int hisi_sfc_v3xx_handle_completion(struct hisi_sfc_v3xx_host *host)
+{
+	u32 reg;
+
+	reg = readl(host->regbase + HISI_SFC_V3XX_RAW_INT_STAT);
+	hisi_sfc_v3xx_clear_int(host);
+
+	if (reg & HISI_SFC_V3XX_INT_MASK_IACCES) {
+		dev_err(host->dev, "fail to access protected address\n");
+		return -EIO;
+	}
+
+	if (reg & HISI_SFC_V3XX_INT_MASK_PP_ERR) {
+		dev_err(host->dev, "page program operation failed\n");
+		return -EIO;
+	}
+
+	/*
+	 * The other bits of the interrupt registers is not currently
+	 * used and probably not be triggered in this driver. When it
+	 * happens, we regard it as an unsupported error here.
+	 */
+	if (!(reg & HISI_SFC_V3XX_INT_MASK_CPLT)) {
+		dev_err(host->dev, "unsupported error occured, status=0x%x\n", reg);
+		return -EIO;
+	}
+
+	return 0;
+}
+
 #define HISI_SFC_V3XX_WAIT_TIMEOUT_US		1000000
 #define HISI_SFC_V3XX_WAIT_POLL_INTERVAL_US	10
 
@@ -79,6 +161,20 @@ static int hisi_sfc_v3xx_adjust_op_size(struct spi_mem *mem,
 	return 0;
 }
 
+/*
+ * The controller only supports Standard SPI mode, Duall mode and
+ * Quad mode. Double sanitize the ops here to avoid OOB access.
+ */
+static bool hisi_sfc_v3xx_supports_op(struct spi_mem *mem,
+				      const struct spi_mem_op *op)
+{
+	if (op->data.buswidth > 4 || op->dummy.buswidth > 4 ||
+	    op->addr.buswidth > 4 || op->cmd.buswidth > 4)
+		return false;
+
+	return spi_mem_default_supports_op(mem, op);
+}
+
 /*
  * memcpy_{to,from}io doesn't gurantee 32b accesses - which we require for the
  * DATABUF registers -so use __io{read,write}32_copy when possible. For
@@ -163,61 +259,36 @@ static void hisi_sfc_v3xx_write_databuf(struct hisi_sfc_v3xx_host *host,
 	}
 }
 
-static int hisi_sfc_v3xx_generic_exec_op(struct hisi_sfc_v3xx_host *host,
-					 const struct spi_mem_op *op,
-					 u8 chip_select)
+static int hisi_sfc_v3xx_start_bus(struct hisi_sfc_v3xx_host *host,
+				   const struct spi_mem_op *op,
+				   u8 chip_select)
 {
-	int ret, len = op->data.nbytes;
-	u32 int_stat, config = 0;
+	int len = op->data.nbytes, buswidth_mode;
+	u32 config = 0;
 
 	if (op->addr.nbytes)
 		config |= HISI_SFC_V3XX_CMD_CFG_ADDR_EN_MSK;
 
-	switch (op->data.buswidth) {
-	case 0 ... 1:
-		break;
-	case 2:
-		if (op->addr.buswidth <= 1) {
-			config |= HISI_SFC_V3XX_CMD_CFG_DUAL_IN_DUAL_OUT;
-		} else if (op->addr.buswidth == 2) {
-			if (op->cmd.buswidth <= 1) {
-				config |= HISI_SFC_V3XX_CMD_CFG_DUAL_IO;
-			} else if (op->cmd.buswidth == 2) {
-				config |= HISI_SFC_V3XX_CMD_CFG_FULL_DIO;
-			} else {
-				return -EIO;
-			}
-		} else {
-			return -EIO;
-		}
-		break;
-	case 4:
-		if (op->addr.buswidth <= 1) {
-			config |= HISI_SFC_V3XX_CMD_CFG_QUAD_IN_QUAD_OUT;
-		} else if (op->addr.buswidth == 4) {
-			if (op->cmd.buswidth <= 1) {
-				config |= HISI_SFC_V3XX_CMD_CFG_QUAD_IO;
-			} else if (op->cmd.buswidth == 4) {
-				config |= HISI_SFC_V3XX_CMD_CFG_FULL_QIO;
-			} else {
-				return -EIO;
-			}
-		} else {
-			return -EIO;
-		}
-		break;
-	default:
-		return -EOPNOTSUPP;
+	if (op->data.buswidth == 0 || op->data.buswidth == 1) {
+		buswidth_mode = HISI_SFC_V3XX_STD;
+	} else {
+		int data_idx, addr_idx, cmd_idx;
+
+		data_idx = (op->data.buswidth - 1) / 2;
+		addr_idx = op->addr.buswidth / 2;
+		cmd_idx = op->cmd.buswidth / 2;
+		buswidth_mode = hisi_sfc_v3xx_io_modes[data_idx][addr_idx][cmd_idx];
 	}
+	if (buswidth_mode < 0)
+		return buswidth_mode;
+	config |= buswidth_mode;
 
 	if (op->data.dir != SPI_MEM_NO_DATA) {
 		config |= (len - 1) << HISI_SFC_V3XX_CMD_CFG_DATA_CNT_OFF;
 		config |= HISI_SFC_V3XX_CMD_CFG_DATA_EN_MSK;
 	}
 
-	if (op->data.dir == SPI_MEM_DATA_OUT)
-		hisi_sfc_v3xx_write_databuf(host, op->data.buf.out, len);
-	else if (op->data.dir == SPI_MEM_DATA_IN)
+	if (op->data.dir == SPI_MEM_DATA_IN)
 		config |= HISI_SFC_V3XX_CMD_CFG_RW_MSK;
 
 	config |= op->dummy.nbytes << HISI_SFC_V3XX_CMD_CFG_DUMMY_CNT_OFF |
@@ -229,31 +300,46 @@ static int hisi_sfc_v3xx_generic_exec_op(struct hisi_sfc_v3xx_host *host,
 
 	writel(config, host->regbase + HISI_SFC_V3XX_CMD_CFG);
 
-	ret = hisi_sfc_v3xx_wait_cmd_idle(host);
+	return 0;
+}
+
+static int hisi_sfc_v3xx_generic_exec_op(struct hisi_sfc_v3xx_host *host,
+					 const struct spi_mem_op *op,
+					 u8 chip_select)
+{
+	DECLARE_COMPLETION_ONSTACK(done);
+	int ret;
+
+	if (host->irq) {
+		host->completion = &done;
+		hisi_sfc_v3xx_enable_int(host);
+	}
+
+	if (op->data.dir == SPI_MEM_DATA_OUT)
+		hisi_sfc_v3xx_write_databuf(host, op->data.buf.out, op->data.nbytes);
+
+	ret = hisi_sfc_v3xx_start_bus(host, op, chip_select);
 	if (ret)
 		return ret;
 
-	/*
-	 * The interrupt status register indicates whether an error occurs
-	 * after per operation. Check it, and clear the interrupts for
-	 * next time judgement.
-	 */
-	int_stat = readl(host->regbase + HISI_SFC_V3XX_INT_STAT);
-	writel(HISI_SFC_V3XX_INT_CLR_CLEAR,
-	       host->regbase + HISI_SFC_V3XX_INT_CLR);
+	if (host->irq) {
+		ret = wait_for_completion_timeout(host->completion,
+						  usecs_to_jiffies(HISI_SFC_V3XX_WAIT_TIMEOUT_US));
+		if (!ret)
+			ret = -ETIMEDOUT;
+		else
+			ret = 0;
 
-	if (int_stat & HISI_SFC_V3XX_INT_STAT_ADDR_IACCES) {
-		dev_err(host->dev, "fail to access protected address\n");
-		return -EIO;
+		hisi_sfc_v3xx_disable_int(host);
+		host->completion = NULL;
+	} else {
+		ret = hisi_sfc_v3xx_wait_cmd_idle(host);
 	}
-
-	if (int_stat & HISI_SFC_V3XX_INT_STAT_PP_ERR) {
-		dev_err(host->dev, "page program operation failed\n");
+	if (hisi_sfc_v3xx_handle_completion(host) || ret)
 		return -EIO;
-	}
 
 	if (op->data.dir == SPI_MEM_DATA_IN)
-		hisi_sfc_v3xx_read_databuf(host, op->data.buf.in, len);
+		hisi_sfc_v3xx_read_databuf(host, op->data.buf.in, op->data.nbytes);
 
 	return 0;
 }
@@ -272,9 +358,21 @@ static int hisi_sfc_v3xx_exec_op(struct spi_mem *mem,
 
 static const struct spi_controller_mem_ops hisi_sfc_v3xx_mem_ops = {
 	.adjust_op_size = hisi_sfc_v3xx_adjust_op_size,
+	.supports_op = hisi_sfc_v3xx_supports_op,
 	.exec_op = hisi_sfc_v3xx_exec_op,
 };
 
+static irqreturn_t hisi_sfc_v3xx_isr(int irq, void *data)
+{
+	struct hisi_sfc_v3xx_host *host = data;
+
+	hisi_sfc_v3xx_disable_int(host);
+
+	complete(host->completion);
+
+	return IRQ_HANDLED;
+}
+
 static int hisi_sfc_v3xx_buswidth_override_bits;
 
 /*
@@ -341,6 +439,26 @@ static int hisi_sfc_v3xx_probe(struct platform_device *pdev)
 		goto err_put_master;
 	}
 
+	host->irq = platform_get_irq_optional(pdev, 0);
+	if (host->irq == -EPROBE_DEFER) {
+		ret = -EPROBE_DEFER;
+		goto err_put_master;
+	}
+
+	hisi_sfc_v3xx_disable_int(host);
+
+	if (host->irq > 0) {
+		ret = devm_request_irq(dev, host->irq, hisi_sfc_v3xx_isr, 0,
+				       "hisi-sfc-v3xx", host);
+
+		if (ret) {
+			dev_err(dev, "failed to request irq%d, ret = %d\n", host->irq, ret);
+			host->irq = 0;
+		}
+	} else {
+		host->irq = 0;
+	}
+
 	ctlr->bus_num = -1;
 	ctlr->num_chipselect = 1;
 	ctlr->mem_ops = &hisi_sfc_v3xx_mem_ops;
@@ -360,7 +478,8 @@ static int hisi_sfc_v3xx_probe(struct platform_device *pdev)
 	if (ret)
 		goto err_put_master;
 
-	dev_info(&pdev->dev, "hw version 0x%x\n", version);
+	dev_info(&pdev->dev, "hw version 0x%x, %s mode.\n",
+		 version, host->irq ? "irq" : "polling");
 
 	return 0;