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From: Witold Sadowski <wsadowski@marvell.com>
To: <linux-kernel@vger.kernel.org>, <linux-spi@vger.kernel.org>,
        <devicetree@vger.kernel.org>
CC: <broonie@kernel.org>, <robh@kernel.org>,
        <krzysztof.kozlowski+dt@linaro.org>, <conor+dt@kernel.org>,
        <pthombar@cadence.com>, Witold Sadowski <wsadowski@marvell.com>
Subject: [PATCH v8 2/4] spi: cadence: Add Marvell xSPI IP overlay changes
Date: Fri, 7 Jun 2024 08:18:29 -0700
Message-ID: <20240607151831.3858304-3-wsadowski@marvell.com>
In-Reply-To: <20240607151831.3858304-1-wsadowski@marvell.com>
References: <20240607151831.3858304-1-wsadowski@marvell.com>
Precedence: bulk
MIME-Version: 1.0
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This commit adds support for the basic v2 Marvell overlay block. Key
features included are:
    - Clock configuration
    - PHY configuration
    - Interrupt configuration (enabling)

The clock divider block, built on top of the Cadence xSPI IP,
divides an external 800MHz clock. It supports a limited range of clock
speeds from 6.25MHz to 200MHz.

To manage interrupts correctly, the driver needs to clear both the MSI-X
interrupt bit and the xSPI interrupt bit. Additionally, interrupt
masking must be disabled.

Signed-off-by: Witold Sadowski <wsadowski@marvell.com>
---
 drivers/spi/spi-cadence-xspi.c | 270 ++++++++++++++++++++++++++++++++-
 1 file changed, 265 insertions(+), 5 deletions(-)

diff --git a/drivers/spi/spi-cadence-xspi.c b/drivers/spi/spi-cadence-xspi.c
index 2e3eacd46b72..566db2591d34 100644
--- a/drivers/spi/spi-cadence-xspi.c
+++ b/drivers/spi/spi-cadence-xspi.c
@@ -193,6 +193,43 @@
 		((op)->data.dir == SPI_MEM_DATA_IN) ? \
 		CDNS_XSPI_STIG_CMD_DIR_READ : CDNS_XSPI_STIG_CMD_DIR_WRITE))
 
+/* PHY default values */
+#define REGS_DLL_PHY_CTRL		0x00000707
+#define CTB_RFILE_PHY_CTRL		0x00004000
+#define RFILE_PHY_TSEL			0x00000000
+#define RFILE_PHY_DQ_TIMING		0x00000101
+#define RFILE_PHY_DQS_TIMING		0x00700404
+#define RFILE_PHY_GATE_LPBK_CTRL	0x00200030
+#define RFILE_PHY_DLL_MASTER_CTRL	0x00800000
+#define RFILE_PHY_DLL_SLAVE_CTRL	0x0000ff01
+
+/* PHY config registers */
+#define CDNS_XSPI_RF_MINICTRL_REGS_DLL_PHY_CTRL			0x1034
+#define CDNS_XSPI_PHY_CTB_RFILE_PHY_CTRL			0x0080
+#define CDNS_XSPI_PHY_CTB_RFILE_PHY_TSEL			0x0084
+#define CDNS_XSPI_PHY_DATASLICE_RFILE_PHY_DQ_TIMING		0x0000
+#define CDNS_XSPI_PHY_DATASLICE_RFILE_PHY_DQS_TIMING		0x0004
+#define CDNS_XSPI_PHY_DATASLICE_RFILE_PHY_GATE_LPBK_CTRL	0x0008
+#define CDNS_XSPI_PHY_DATASLICE_RFILE_PHY_DLL_MASTER_CTRL	0x000c
+#define CDNS_XSPI_PHY_DATASLICE_RFILE_PHY_DLL_SLAVE_CTRL	0x0010
+#define CDNS_XSPI_DATASLICE_RFILE_PHY_DLL_OBS_REG_0		0x001c
+
+#define CDNS_XSPI_DLL_RST_N BIT(24)
+#define CDNS_XSPI_DLL_LOCK  BIT(0)
+
+/* Marvell overlay registers - clock */
+#define MRVL_XSPI_CLK_CTRL_AUX_REG   0x2020
+#define MRVL_XSPI_CLK_ENABLE	     BIT(0)
+#define MRVL_XSPI_CLK_DIV	     GENMASK(4, 1)
+#define MRVL_XSPI_IRQ_ENABLE	     BIT(6)
+#define MRVL_XSPI_CLOCK_IO_HZ	     800000000
+#define MRVL_XSPI_CLOCK_DIVIDED(div) ((MRVL_XSPI_CLOCK_IO_HZ) / (div))
+#define MRVL_DEFAULT_CLK	     25000000
+
+/* Marvell overlay registers - MSI-X */
+#define MRVL_XSPI_SPIX_INTR_AUX	0x2000
+#define MRVL_MSIX_CLEAR_IRQ	0x01
+
 enum cdns_xspi_stig_instr_type {
 	CDNS_XSPI_STIG_INSTR_TYPE_0,
 	CDNS_XSPI_STIG_INSTR_TYPE_1,
@@ -212,6 +249,7 @@ enum cdns_xspi_stig_cmd_dir {
 struct cdns_xspi_dev {
 	struct platform_device *pdev;
 	struct device *dev;
+	bool mrvl_hw_overlay;
 
 	void __iomem *iobase;
 	void __iomem *auxbase;
@@ -232,6 +270,123 @@ struct cdns_xspi_dev {
 	u8 hw_num_banks;
 };
 
+struct cdns_xspi_driver_data {
+	bool mrvl_hw_overlay;
+};
+
+static struct cdns_xspi_driver_data mrvl_driver_data = {
+	.mrvl_hw_overlay = true,
+};
+
+static struct cdns_xspi_driver_data cdns_driver_data = {
+	.mrvl_hw_overlay = false,
+};
+
+const int cdns_mrvl_xspi_clk_div_list[] = {
+	4,	//0x0 = Divide by 4.   SPI clock is 200 MHz.
+	6,	//0x1 = Divide by 6.   SPI clock is 133.33 MHz.
+	8,	//0x2 = Divide by 8.   SPI clock is 100 MHz.
+	10,	//0x3 = Divide by 10.  SPI clock is 80 MHz.
+	12,	//0x4 = Divide by 12.  SPI clock is 66.666 MHz.
+	16,	//0x5 = Divide by 16.  SPI clock is 50 MHz.
+	18,	//0x6 = Divide by 18.  SPI clock is 44.44 MHz.
+	20,	//0x7 = Divide by 20.  SPI clock is 40 MHz.
+	24,	//0x8 = Divide by 24.  SPI clock is 33.33 MHz.
+	32,	//0x9 = Divide by 32.  SPI clock is 25 MHz.
+	40,	//0xA = Divide by 40.  SPI clock is 20 MHz.
+	50,	//0xB = Divide by 50.  SPI clock is 16 MHz.
+	64,	//0xC = Divide by 64.  SPI clock is 12.5 MHz.
+	128	//0xD = Divide by 128. SPI clock is 6.25 MHz.
+};
+
+static void cdns_xspi_reset_dll(struct cdns_xspi_dev *cdns_xspi)
+{
+	u32 dll_cntrl = readl(cdns_xspi->iobase +
+			      CDNS_XSPI_RF_MINICTRL_REGS_DLL_PHY_CTRL);
+
+	/* Reset DLL */
+	dll_cntrl |= CDNS_XSPI_DLL_RST_N;
+	writel(dll_cntrl, cdns_xspi->iobase +
+			  CDNS_XSPI_RF_MINICTRL_REGS_DLL_PHY_CTRL);
+}
+
+static bool cdns_xspi_is_dll_locked(struct cdns_xspi_dev *cdns_xspi)
+{
+	u32 dll_lock;
+
+	return !readl_relaxed_poll_timeout(cdns_xspi->iobase +
+		CDNS_XSPI_INTR_STATUS_REG,
+		dll_lock, ((dll_lock & CDNS_XSPI_DLL_LOCK) == 1), 10, 10000);
+}
+
+/* Static configuration of PHY */
+static bool cdns_xspi_configure_phy(struct cdns_xspi_dev *cdns_xspi)
+{
+	writel(REGS_DLL_PHY_CTRL,
+	       cdns_xspi->iobase + CDNS_XSPI_RF_MINICTRL_REGS_DLL_PHY_CTRL);
+	writel(CTB_RFILE_PHY_CTRL,
+	       cdns_xspi->auxbase + CDNS_XSPI_PHY_CTB_RFILE_PHY_CTRL);
+	writel(RFILE_PHY_TSEL,
+	       cdns_xspi->auxbase + CDNS_XSPI_PHY_CTB_RFILE_PHY_TSEL);
+	writel(RFILE_PHY_DQ_TIMING,
+	       cdns_xspi->auxbase + CDNS_XSPI_PHY_DATASLICE_RFILE_PHY_DQ_TIMING);
+	writel(RFILE_PHY_DQS_TIMING,
+	       cdns_xspi->auxbase + CDNS_XSPI_PHY_DATASLICE_RFILE_PHY_DQS_TIMING);
+	writel(RFILE_PHY_GATE_LPBK_CTRL,
+	       cdns_xspi->auxbase + CDNS_XSPI_PHY_DATASLICE_RFILE_PHY_GATE_LPBK_CTRL);
+	writel(RFILE_PHY_DLL_MASTER_CTRL,
+	       cdns_xspi->auxbase + CDNS_XSPI_PHY_DATASLICE_RFILE_PHY_DLL_MASTER_CTRL);
+	writel(RFILE_PHY_DLL_SLAVE_CTRL,
+	       cdns_xspi->auxbase + CDNS_XSPI_PHY_DATASLICE_RFILE_PHY_DLL_SLAVE_CTRL);
+
+	cdns_xspi_reset_dll(cdns_xspi);
+
+	return cdns_xspi_is_dll_locked(cdns_xspi);
+}
+
+/* Find max avalible clock */
+static bool cdns_mrvl_xspi_setup_clock(struct cdns_xspi_dev *cdns_xspi,
+				       int requested_clk)
+{
+	int i = 0;
+	int clk_val;
+	u32 clk_reg;
+	bool update_clk = false;
+
+	while (i < ARRAY_SIZE(cdns_mrvl_xspi_clk_div_list)) {
+		clk_val = MRVL_XSPI_CLOCK_DIVIDED(
+				cdns_mrvl_xspi_clk_div_list[i]);
+		if (clk_val <= requested_clk)
+			break;
+		i++;
+	}
+
+	dev_dbg(cdns_xspi->dev, "Found clk div: %d, clk val: %d\n",
+		cdns_mrvl_xspi_clk_div_list[i],
+		MRVL_XSPI_CLOCK_DIVIDED(
+		cdns_mrvl_xspi_clk_div_list[i]));
+
+	clk_reg = readl(cdns_xspi->auxbase + MRVL_XSPI_CLK_CTRL_AUX_REG);
+
+	if (FIELD_GET(MRVL_XSPI_CLK_DIV, clk_reg) != i) {
+		clk_reg &= ~MRVL_XSPI_CLK_ENABLE;
+		writel(clk_reg,
+		       cdns_xspi->auxbase + MRVL_XSPI_CLK_CTRL_AUX_REG);
+		clk_reg = FIELD_PREP(MRVL_XSPI_CLK_DIV, i);
+		clk_reg &= ~MRVL_XSPI_CLK_DIV;
+		clk_reg |= FIELD_PREP(MRVL_XSPI_CLK_DIV, i);
+		clk_reg |= MRVL_XSPI_CLK_ENABLE;
+		clk_reg |= MRVL_XSPI_IRQ_ENABLE;
+		update_clk = true;
+	}
+
+	if (update_clk)
+		writel(clk_reg,
+		       cdns_xspi->auxbase + MRVL_XSPI_CLK_CTRL_AUX_REG);
+
+	return update_clk;
+}
+
 static int cdns_xspi_wait_for_controller_idle(struct cdns_xspi_dev *cdns_xspi)
 {
 	u32 ctrl_stat;
@@ -295,6 +450,10 @@ static void cdns_xspi_set_interrupts(struct cdns_xspi_dev *cdns_xspi,
 				     bool enabled)
 {
 	u32 intr_enable;
+	u32 irq_status;
+
+	irq_status = readl(cdns_xspi->iobase + CDNS_XSPI_INTR_STATUS_REG);
+	writel(irq_status, cdns_xspi->iobase + CDNS_XSPI_INTR_STATUS_REG);
 
 	intr_enable = readl(cdns_xspi->iobase + CDNS_XSPI_INTR_ENABLE_REG);
 	if (enabled)
@@ -319,6 +478,9 @@ static int cdns_xspi_controller_init(struct cdns_xspi_dev *cdns_xspi)
 		return -EIO;
 	}
 
+	writel(FIELD_PREP(CDNS_XSPI_CTRL_WORK_MODE, CDNS_XSPI_WORK_MODE_STIG),
+	       cdns_xspi->iobase + CDNS_XSPI_CTRL_CONFIG_REG);
+
 	ctrl_features = readl(cdns_xspi->iobase + CDNS_XSPI_CTRL_FEATURES_REG);
 	cdns_xspi->hw_num_banks = FIELD_GET(CDNS_XSPI_NUM_BANKS, ctrl_features);
 	cdns_xspi_set_interrupts(cdns_xspi, false);
@@ -326,6 +488,70 @@ static int cdns_xspi_controller_init(struct cdns_xspi_dev *cdns_xspi)
 	return 0;
 }
 
+static void mrvl_ioreadq(void __iomem  *addr, void *buf, int len)
+{
+	int i = 0;
+	int rcount = len / 8;
+	int rcount_nf = len % 8;
+	uint64_t tmp;
+	uint64_t *buf64 = (uint64_t *)buf;
+
+	if (((uint64_t)buf % 8) == 0) {
+		for (i = 0; i < rcount; i++)
+			*buf64++ = readq(addr);
+	} else {
+		for (i = 0; i < rcount; i++) {
+			tmp = readq(addr);
+			memcpy(buf+(i*8), &tmp, 8);
+		}
+	}
+
+	if (rcount_nf != 0) {
+		tmp = readq(addr);
+		memcpy(buf+(i*8), &tmp, rcount_nf);
+	}
+}
+
+static void mrvl_iowriteq(void __iomem *addr, const void *buf, int len)
+{
+	int i = 0;
+	int rcount = len / 8;
+	int rcount_nf = len % 8;
+	uint64_t tmp;
+	uint64_t *buf64 = (uint64_t *)buf;
+
+	if (((uint64_t)buf % 8) == 0) {
+		for (i = 0; i < rcount; i++)
+			writeq(*buf64++, addr);
+	} else {
+		for (i = 0; i < rcount; i++) {
+			memcpy(&tmp, buf+(i*8), 8);
+			writeq(tmp, addr);
+		}
+	}
+
+	if (rcount_nf != 0) {
+		memcpy(&tmp, buf+(i*8), rcount_nf);
+		writeq(tmp, addr);
+	}
+}
+
+static void cdns_xspi_sdma_memread(struct cdns_xspi_dev *cdns_xspi, int len)
+{
+	if (cdns_xspi->mrvl_hw_overlay)
+		mrvl_ioreadq(cdns_xspi->sdmabase, cdns_xspi->in_buffer, len);
+	else
+		ioread8_rep(cdns_xspi->sdmabase, cdns_xspi->in_buffer, len);
+}
+
+static void cdns_xspi_sdma_memwrite(struct cdns_xspi_dev *cdns_xspi, int len)
+{
+	if (cdns_xspi->mrvl_hw_overlay)
+		mrvl_iowriteq(cdns_xspi->sdmabase, cdns_xspi->out_buffer, len);
+	else
+		iowrite8_rep(cdns_xspi->sdmabase, cdns_xspi->out_buffer, len);
+}
+
 static void cdns_xspi_sdma_handle(struct cdns_xspi_dev *cdns_xspi)
 {
 	u32 sdma_size, sdma_trd_info;
@@ -337,13 +563,11 @@ static void cdns_xspi_sdma_handle(struct cdns_xspi_dev *cdns_xspi)
 
 	switch (sdma_dir) {
 	case CDNS_XSPI_SDMA_DIR_READ:
-		ioread8_rep(cdns_xspi->sdmabase,
-			    cdns_xspi->in_buffer, sdma_size);
+		cdns_xspi_sdma_memread(cdns_xspi, sdma_size);
 		break;
 
 	case CDNS_XSPI_SDMA_DIR_WRITE:
-		iowrite8_rep(cdns_xspi->sdmabase,
-			     cdns_xspi->out_buffer, sdma_size);
+		cdns_xspi_sdma_memwrite(cdns_xspi, sdma_size);
 		break;
 	}
 }
@@ -421,6 +645,9 @@ static int cdns_xspi_mem_op(struct cdns_xspi_dev *cdns_xspi,
 	if (cdns_xspi->cur_cs != spi_get_chipselect(mem->spi, 0))
 		cdns_xspi->cur_cs = spi_get_chipselect(mem->spi, 0);
 
+	if (cdns_xspi->mrvl_hw_overlay)
+		cdns_mrvl_xspi_setup_clock(cdns_xspi, mem->spi->max_speed_hz);
+
 	return cdns_xspi_send_stig_command(cdns_xspi, op,
 					   (dir != SPI_MEM_NO_DATA));
 }
@@ -461,6 +688,10 @@ static irqreturn_t cdns_xspi_irq_handler(int this_irq, void *dev)
 	irq_status = readl(cdns_xspi->iobase + CDNS_XSPI_INTR_STATUS_REG);
 	writel(irq_status, cdns_xspi->iobase + CDNS_XSPI_INTR_STATUS_REG);
 
+	if (cdns_xspi->mrvl_hw_overlay)
+		writel(MRVL_MSIX_CLEAR_IRQ,
+		       cdns_xspi->auxbase + MRVL_XSPI_SPIX_INTR_AUX);
+
 	if (irq_status &
 	    (CDNS_XSPI_SDMA_ERROR | CDNS_XSPI_SDMA_TRIGGER |
 	     CDNS_XSPI_STIG_DONE)) {
@@ -528,11 +759,23 @@ static void cdns_xspi_print_phy_config(struct cdns_xspi_dev *cdns_xspi)
 		 readl(cdns_xspi->auxbase + CDNS_XSPI_CCP_PHY_DLL_SLAVE_CTRL));
 }
 
+static int cdns_xspi_setup(struct spi_device *spi_dev)
+{
+	struct cdns_xspi_dev *cdns_xspi = spi_controller_get_devdata(
+						spi_dev->controller);
+
+	if (cdns_xspi->mrvl_hw_overlay)
+		cdns_mrvl_xspi_setup_clock(cdns_xspi, spi_dev->max_speed_hz);
+
+	return 0;
+}
+
 static int cdns_xspi_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
 	struct spi_controller *host = NULL;
 	struct cdns_xspi_dev *cdns_xspi = NULL;
+	const struct cdns_xspi_driver_data *drv_data;
 	struct resource *res;
 	int ret;
 
@@ -544,10 +787,16 @@ static int cdns_xspi_probe(struct platform_device *pdev)
 		SPI_RX_DUAL | SPI_RX_QUAD | SPI_TX_OCTAL | SPI_RX_OCTAL |
 		SPI_MODE_0  | SPI_MODE_3;
 
+	drv_data = of_device_get_match_data(dev);
+
 	host->mem_ops = &cadence_xspi_mem_ops;
 	host->dev.of_node = pdev->dev.of_node;
+	host->dev.fwnode = pdev->dev.fwnode;
 	host->bus_num = -1;
 
+	if (drv_data->mrvl_hw_overlay)
+		host->setup = cdns_xspi_setup;
+
 	platform_set_drvdata(pdev, host);
 
 	cdns_xspi = spi_controller_get_devdata(host);
@@ -559,6 +808,8 @@ static int cdns_xspi_probe(struct platform_device *pdev)
 	init_completion(&cdns_xspi->auto_cmd_complete);
 	init_completion(&cdns_xspi->sdma_complete);
 
+	cdns_xspi->mrvl_hw_overlay = drv_data->mrvl_hw_overlay;
+
 	ret = cdns_xspi_of_get_plat_data(pdev);
 	if (ret)
 		return -ENODEV;
@@ -592,8 +843,12 @@ static int cdns_xspi_probe(struct platform_device *pdev)
 		return ret;
 	}
 
-	cdns_xspi_print_phy_config(cdns_xspi);
+	if (drv_data->mrvl_hw_overlay) {
+		cdns_mrvl_xspi_setup_clock(cdns_xspi, MRVL_DEFAULT_CLK);
+		cdns_xspi_configure_phy(cdns_xspi);
+	}
 
+	cdns_xspi_print_phy_config(cdns_xspi);
 	ret = cdns_xspi_controller_init(cdns_xspi);
 	if (ret) {
 		dev_err(dev, "Failed to initialize controller\n");
@@ -616,6 +871,11 @@ static int cdns_xspi_probe(struct platform_device *pdev)
 static const struct of_device_id cdns_xspi_of_match[] = {
 	{
 		.compatible = "cdns,xspi-nor",
+		.data = &cdns_driver_data,
+	},
+	{
+		.compatible = "marvell,cn10-xspi-nor",
+		.data = &mrvl_driver_data,
 	},
 	{ /* end of table */}
 };
-- 
2.43.0