summaryrefslogtreecommitdiff
path: root/drivers/spi/atmel-quadspi.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/spi/atmel-quadspi.c')
-rw-r--r--drivers/spi/atmel-quadspi.c549
1 files changed, 549 insertions, 0 deletions
diff --git a/drivers/spi/atmel-quadspi.c b/drivers/spi/atmel-quadspi.c
new file mode 100644
index 000000000000..ddc712410812
--- /dev/null
+++ b/drivers/spi/atmel-quadspi.c
@@ -0,0 +1,549 @@
+/*
+ * Driver for Atmel QSPI Controller
+ *
+ * Copyright (C) 2015 Atmel Corporation
+ * Copyright (C) 2018 Cryptera A/S
+ *
+ * Author: Cyrille Pitchen <cyrille.pitchen@atmel.com>
+ * Author: Piotr Bugalski <bugalski.piotr@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * This driver is based on drivers/mtd/spi-nor/fsl-quadspi.c from Freescale.
+ */
+
+#include <linux/kernel.h>
+#include <linux/clk.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/of.h>
+
+#include <linux/io.h>
+#include <linux/spi/spi-mem.h>
+
+/* QSPI register offsets */
+#define QSPI_CR 0x0000 /* Control Register */
+#define QSPI_MR 0x0004 /* Mode Register */
+#define QSPI_RD 0x0008 /* Receive Data Register */
+#define QSPI_TD 0x000c /* Transmit Data Register */
+#define QSPI_SR 0x0010 /* Status Register */
+#define QSPI_IER 0x0014 /* Interrupt Enable Register */
+#define QSPI_IDR 0x0018 /* Interrupt Disable Register */
+#define QSPI_IMR 0x001c /* Interrupt Mask Register */
+#define QSPI_SCR 0x0020 /* Serial Clock Register */
+
+#define QSPI_IAR 0x0030 /* Instruction Address Register */
+#define QSPI_ICR 0x0034 /* Instruction Code Register */
+#define QSPI_IFR 0x0038 /* Instruction Frame Register */
+
+#define QSPI_SMR 0x0040 /* Scrambling Mode Register */
+#define QSPI_SKR 0x0044 /* Scrambling Key Register */
+
+#define QSPI_WPMR 0x00E4 /* Write Protection Mode Register */
+#define QSPI_WPSR 0x00E8 /* Write Protection Status Register */
+
+#define QSPI_VERSION 0x00FC /* Version Register */
+
+
+/* Bitfields in QSPI_CR (Control Register) */
+#define QSPI_CR_QSPIEN BIT(0)
+#define QSPI_CR_QSPIDIS BIT(1)
+#define QSPI_CR_SWRST BIT(7)
+#define QSPI_CR_LASTXFER BIT(24)
+
+/* Bitfields in QSPI_MR (Mode Register) */
+#define QSPI_MR_SMM BIT(0)
+#define QSPI_MR_LLB BIT(1)
+#define QSPI_MR_WDRBT BIT(2)
+#define QSPI_MR_SMRM BIT(3)
+#define QSPI_MR_CSMODE_MASK GENMASK(5, 4)
+#define QSPI_MR_CSMODE_NOT_RELOADED (0 << 4)
+#define QSPI_MR_CSMODE_LASTXFER (1 << 4)
+#define QSPI_MR_CSMODE_SYSTEMATICALLY (2 << 4)
+#define QSPI_MR_NBBITS_MASK GENMASK(11, 8)
+#define QSPI_MR_NBBITS(n) ((((n) - 8) << 8) & QSPI_MR_NBBITS_MASK)
+#define QSPI_MR_DLYBCT_MASK GENMASK(23, 16)
+#define QSPI_MR_DLYBCT(n) (((n) << 16) & QSPI_MR_DLYBCT_MASK)
+#define QSPI_MR_DLYCS_MASK GENMASK(31, 24)
+#define QSPI_MR_DLYCS(n) (((n) << 24) & QSPI_MR_DLYCS_MASK)
+
+/* Bitfields in QSPI_SR/QSPI_IER/QSPI_IDR/QSPI_IMR */
+#define QSPI_SR_RDRF BIT(0)
+#define QSPI_SR_TDRE BIT(1)
+#define QSPI_SR_TXEMPTY BIT(2)
+#define QSPI_SR_OVRES BIT(3)
+#define QSPI_SR_CSR BIT(8)
+#define QSPI_SR_CSS BIT(9)
+#define QSPI_SR_INSTRE BIT(10)
+#define QSPI_SR_QSPIENS BIT(24)
+
+#define QSPI_SR_CMD_COMPLETED (QSPI_SR_INSTRE | QSPI_SR_CSR)
+
+/* Bitfields in QSPI_SCR (Serial Clock Register) */
+#define QSPI_SCR_CPOL BIT(0)
+#define QSPI_SCR_CPHA BIT(1)
+#define QSPI_SCR_SCBR_MASK GENMASK(15, 8)
+#define QSPI_SCR_SCBR(n) (((n) << 8) & QSPI_SCR_SCBR_MASK)
+#define QSPI_SCR_DLYBS_MASK GENMASK(23, 16)
+#define QSPI_SCR_DLYBS(n) (((n) << 16) & QSPI_SCR_DLYBS_MASK)
+
+/* Bitfields in QSPI_ICR (Instruction Code Register) */
+#define QSPI_ICR_INST_MASK GENMASK(7, 0)
+#define QSPI_ICR_INST(inst) (((inst) << 0) & QSPI_ICR_INST_MASK)
+#define QSPI_ICR_OPT_MASK GENMASK(23, 16)
+#define QSPI_ICR_OPT(opt) (((opt) << 16) & QSPI_ICR_OPT_MASK)
+
+/* Bitfields in QSPI_IFR (Instruction Frame Register) */
+#define QSPI_IFR_WIDTH_MASK GENMASK(2, 0)
+#define QSPI_IFR_WIDTH_SINGLE_BIT_SPI (0 << 0)
+#define QSPI_IFR_WIDTH_DUAL_OUTPUT (1 << 0)
+#define QSPI_IFR_WIDTH_QUAD_OUTPUT (2 << 0)
+#define QSPI_IFR_WIDTH_DUAL_IO (3 << 0)
+#define QSPI_IFR_WIDTH_QUAD_IO (4 << 0)
+#define QSPI_IFR_WIDTH_DUAL_CMD (5 << 0)
+#define QSPI_IFR_WIDTH_QUAD_CMD (6 << 0)
+#define QSPI_IFR_INSTEN BIT(4)
+#define QSPI_IFR_ADDREN BIT(5)
+#define QSPI_IFR_OPTEN BIT(6)
+#define QSPI_IFR_DATAEN BIT(7)
+#define QSPI_IFR_OPTL_MASK GENMASK(9, 8)
+#define QSPI_IFR_OPTL_1BIT (0 << 8)
+#define QSPI_IFR_OPTL_2BIT (1 << 8)
+#define QSPI_IFR_OPTL_4BIT (2 << 8)
+#define QSPI_IFR_OPTL_8BIT (3 << 8)
+#define QSPI_IFR_ADDRL BIT(10)
+#define QSPI_IFR_TFRTYP_MASK GENMASK(13, 12)
+#define QSPI_IFR_TFRTYP_TRSFR_READ (0 << 12)
+#define QSPI_IFR_TFRTYP_TRSFR_READ_MEM (1 << 12)
+#define QSPI_IFR_TFRTYP_TRSFR_WRITE (2 << 12)
+#define QSPI_IFR_TFRTYP_TRSFR_WRITE_MEM (3 << 13)
+#define QSPI_IFR_CRM BIT(14)
+#define QSPI_IFR_NBDUM_MASK GENMASK(20, 16)
+#define QSPI_IFR_NBDUM(n) (((n) << 16) & QSPI_IFR_NBDUM_MASK)
+
+/* Bitfields in QSPI_SMR (Scrambling Mode Register) */
+#define QSPI_SMR_SCREN BIT(0)
+#define QSPI_SMR_RVDIS BIT(1)
+
+/* Bitfields in QSPI_WPMR (Write Protection Mode Register) */
+#define QSPI_WPMR_WPEN BIT(0)
+#define QSPI_WPMR_WPKEY_MASK GENMASK(31, 8)
+#define QSPI_WPMR_WPKEY(wpkey) (((wpkey) << 8) & QSPI_WPMR_WPKEY_MASK)
+
+/* Bitfields in QSPI_WPSR (Write Protection Status Register) */
+#define QSPI_WPSR_WPVS BIT(0)
+#define QSPI_WPSR_WPVSRC_MASK GENMASK(15, 8)
+#define QSPI_WPSR_WPVSRC(src) (((src) << 8) & QSPI_WPSR_WPVSRC)
+
+
+struct atmel_qspi {
+ void __iomem *regs;
+ void __iomem *mem;
+ struct clk *clk;
+ struct platform_device *pdev;
+ u32 pending;
+ struct completion cmd_completion;
+};
+
+struct qspi_mode {
+ u8 cmd_buswidth;
+ u8 addr_buswidth;
+ u8 data_buswidth;
+ u32 config;
+};
+
+static const struct qspi_mode sama5d2_qspi_modes[] = {
+ { 1, 1, 1, QSPI_IFR_WIDTH_SINGLE_BIT_SPI },
+ { 1, 1, 2, QSPI_IFR_WIDTH_DUAL_OUTPUT },
+ { 1, 1, 4, QSPI_IFR_WIDTH_QUAD_OUTPUT },
+ { 1, 2, 2, QSPI_IFR_WIDTH_DUAL_IO },
+ { 1, 4, 4, QSPI_IFR_WIDTH_QUAD_IO },
+ { 2, 2, 2, QSPI_IFR_WIDTH_DUAL_CMD },
+ { 4, 4, 4, QSPI_IFR_WIDTH_QUAD_CMD },
+};
+
+/* Register access functions */
+static inline u32 qspi_readl(struct atmel_qspi *aq, u32 reg)
+{
+ return readl_relaxed(aq->regs + reg);
+}
+
+static inline void qspi_writel(struct atmel_qspi *aq, u32 reg, u32 value)
+{
+ writel_relaxed(value, aq->regs + reg);
+}
+
+static inline bool is_compatible(const struct spi_mem_op *op,
+ const struct qspi_mode *mode)
+{
+ if (op->cmd.buswidth != mode->cmd_buswidth)
+ return false;
+
+ if (op->addr.nbytes && op->addr.buswidth != mode->addr_buswidth)
+ return false;
+
+ if (op->data.nbytes && op->data.buswidth != mode->data_buswidth)
+ return false;
+
+ return true;
+}
+
+static int find_mode(const struct spi_mem_op *op)
+{
+ u32 i;
+
+ for (i = 0; i < ARRAY_SIZE(sama5d2_qspi_modes); i++)
+ if (is_compatible(op, &sama5d2_qspi_modes[i]))
+ return i;
+
+ return -1;
+}
+
+static bool atmel_qspi_supports_op(struct spi_mem *mem,
+ const struct spi_mem_op *op)
+{
+ if (find_mode(op) < 0)
+ return false;
+
+ /* special case not supported by hardware */
+ if (op->addr.nbytes == 2 && op->cmd.buswidth != op->addr.buswidth &&
+ op->dummy.nbytes == 0)
+ return false;
+
+ return true;
+}
+
+static int atmel_qspi_exec_op(struct spi_mem *mem, const struct spi_mem_op *op)
+{
+ struct atmel_qspi *aq = spi_controller_get_devdata(mem->spi->master);
+ int mode;
+ u32 dummy_cycles = 0;
+ u32 iar, icr, ifr, sr;
+ int err = 0;
+
+ iar = 0;
+ icr = QSPI_ICR_INST(op->cmd.opcode);
+ ifr = QSPI_IFR_INSTEN;
+
+ qspi_writel(aq, QSPI_MR, QSPI_MR_SMM);
+
+ mode = find_mode(op);
+ if (mode < 0)
+ return -ENOTSUPP;
+
+ ifr |= sama5d2_qspi_modes[mode].config;
+
+ if (op->dummy.buswidth && op->dummy.nbytes)
+ dummy_cycles = op->dummy.nbytes * 8 / op->dummy.buswidth;
+
+ if (op->addr.buswidth) {
+ switch (op->addr.nbytes) {
+ case 0:
+ break;
+ case 1:
+ ifr |= QSPI_IFR_OPTEN | QSPI_IFR_OPTL_8BIT;
+ icr |= QSPI_ICR_OPT(op->addr.val & 0xff);
+ break;
+ case 2:
+ if (dummy_cycles < 8 / op->addr.buswidth) {
+ ifr &= ~QSPI_IFR_INSTEN;
+ ifr |= QSPI_IFR_ADDREN;
+ iar = (op->cmd.opcode << 16) |
+ (op->addr.val & 0xffff);
+ } else {
+ ifr |= QSPI_IFR_ADDREN;
+ iar = (op->addr.val << 8) & 0xffffff;
+ dummy_cycles -= 8 / op->addr.buswidth;
+ }
+ break;
+ case 3:
+ ifr |= QSPI_IFR_ADDREN;
+ iar = op->addr.val & 0xffffff;
+ break;
+ case 4:
+ ifr |= QSPI_IFR_ADDREN | QSPI_IFR_ADDRL;
+ iar = op->addr.val & 0x7ffffff;
+ break;
+ default:
+ return -ENOTSUPP;
+ }
+ }
+
+ /* Set number of dummy cycles */
+ if (dummy_cycles)
+ ifr |= QSPI_IFR_NBDUM(dummy_cycles);
+
+ /* Set data enable */
+ if (op->data.nbytes)
+ ifr |= QSPI_IFR_DATAEN;
+
+ if (op->data.dir == SPI_MEM_DATA_IN && op->data.nbytes)
+ ifr |= QSPI_IFR_TFRTYP_TRSFR_READ;
+ else
+ ifr |= QSPI_IFR_TFRTYP_TRSFR_WRITE;
+
+ /* Clear pending interrupts */
+ (void)qspi_readl(aq, QSPI_SR);
+
+ /* Set QSPI Instruction Frame registers */
+ qspi_writel(aq, QSPI_IAR, iar);
+ qspi_writel(aq, QSPI_ICR, icr);
+ qspi_writel(aq, QSPI_IFR, ifr);
+
+ /* Skip to the final steps if there is no data */
+ if (op->data.nbytes) {
+ /* Dummy read of QSPI_IFR to synchronize APB and AHB accesses */
+ (void)qspi_readl(aq, QSPI_IFR);
+
+ /* Send/Receive data */
+ if (op->data.dir == SPI_MEM_DATA_IN)
+ _memcpy_fromio(op->data.buf.in,
+ aq->mem + iar, op->data.nbytes);
+ else
+ _memcpy_toio(aq->mem + iar,
+ op->data.buf.out, op->data.nbytes);
+
+ /* Release the chip-select */
+ qspi_writel(aq, QSPI_CR, QSPI_CR_LASTXFER);
+ }
+
+ /* Poll INSTRuction End status */
+ sr = qspi_readl(aq, QSPI_SR);
+ if ((sr & QSPI_SR_CMD_COMPLETED) == QSPI_SR_CMD_COMPLETED)
+ return err;
+
+ /* Wait for INSTRuction End interrupt */
+ reinit_completion(&aq->cmd_completion);
+ aq->pending = sr & QSPI_SR_CMD_COMPLETED;
+ qspi_writel(aq, QSPI_IER, QSPI_SR_CMD_COMPLETED);
+ if (!wait_for_completion_timeout(&aq->cmd_completion,
+ msecs_to_jiffies(1000)))
+ err = -ETIMEDOUT;
+ qspi_writel(aq, QSPI_IDR, QSPI_SR_CMD_COMPLETED);
+
+ return err;
+}
+
+const char *atmel_qspi_get_name(struct spi_mem *spimem)
+{
+ return dev_name(spimem->spi->dev.parent);
+}
+
+static const struct spi_controller_mem_ops atmel_qspi_mem_ops = {
+ .supports_op = atmel_qspi_supports_op,
+ .exec_op = atmel_qspi_exec_op,
+ .get_name = atmel_qspi_get_name
+};
+
+static int atmel_qspi_setup(struct spi_device *spi)
+{
+ struct spi_controller *ctrl = spi->master;
+ struct atmel_qspi *aq = spi_controller_get_devdata(ctrl);
+ unsigned long src_rate;
+ u32 scr, scbr;
+
+ if (ctrl->busy)
+ return -EBUSY;
+
+ if (!spi->max_speed_hz)
+ return -EINVAL;
+
+ src_rate = clk_get_rate(aq->clk);
+ if (!src_rate)
+ return -EINVAL;
+
+ /* Compute the QSPI baudrate */
+ scbr = DIV_ROUND_UP(src_rate, spi->max_speed_hz);
+ if (scbr > 0)
+ scbr--;
+
+ scr = QSPI_SCR_SCBR(scbr);
+ qspi_writel(aq, QSPI_SCR, scr);
+
+ return 0;
+}
+
+static int atmel_qspi_init(struct atmel_qspi *aq)
+{
+ /* Reset the QSPI controller */
+ qspi_writel(aq, QSPI_CR, QSPI_CR_SWRST);
+
+ /* Enable the QSPI controller */
+ qspi_writel(aq, QSPI_CR, QSPI_CR_QSPIEN);
+
+ return 0;
+}
+
+static irqreturn_t atmel_qspi_interrupt(int irq, void *dev_id)
+{
+ struct atmel_qspi *aq = (struct atmel_qspi *)dev_id;
+ u32 status, mask, pending;
+
+ status = qspi_readl(aq, QSPI_SR);
+ mask = qspi_readl(aq, QSPI_IMR);
+ pending = status & mask;
+
+ if (!pending)
+ return IRQ_NONE;
+
+ aq->pending |= pending;
+ if ((aq->pending & QSPI_SR_CMD_COMPLETED) == QSPI_SR_CMD_COMPLETED)
+ complete(&aq->cmd_completion);
+
+ return IRQ_HANDLED;
+}
+
+static int atmel_qspi_probe(struct platform_device *pdev)
+{
+ struct spi_controller *ctrl;
+ struct atmel_qspi *aq;
+ struct resource *res;
+ int irq, err = 0;
+
+ ctrl = spi_alloc_master(&pdev->dev, sizeof(*aq));
+ if (!ctrl)
+ return -ENOMEM;
+
+ ctrl->mode_bits = SPI_RX_DUAL | SPI_RX_QUAD | SPI_TX_DUAL | SPI_TX_QUAD;
+ ctrl->setup = atmel_qspi_setup;
+ ctrl->bus_num = -1;
+ ctrl->mem_ops = &atmel_qspi_mem_ops;
+ ctrl->num_chipselect = 1;
+ ctrl->dev.of_node = pdev->dev.of_node;
+ platform_set_drvdata(pdev, ctrl);
+
+ aq = spi_controller_get_devdata(ctrl);
+
+ init_completion(&aq->cmd_completion);
+ aq->pdev = pdev;
+
+ /* Map the registers */
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "qspi_base");
+ aq->regs = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(aq->regs)) {
+ dev_err(&pdev->dev, "missing registers\n");
+ err = PTR_ERR(aq->regs);
+ goto exit;
+ }
+
+ /* Map the AHB memory */
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "qspi_mmap");
+ aq->mem = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(aq->mem)) {
+ dev_err(&pdev->dev, "missing AHB memory\n");
+ err = PTR_ERR(aq->mem);
+ goto exit;
+ }
+
+ /* Get the peripheral clock */
+ aq->clk = devm_clk_get(&pdev->dev, NULL);
+ if (IS_ERR(aq->clk)) {
+ dev_err(&pdev->dev, "missing peripheral clock\n");
+ err = PTR_ERR(aq->clk);
+ goto exit;
+ }
+
+ /* Enable the peripheral clock */
+ err = clk_prepare_enable(aq->clk);
+ if (err) {
+ dev_err(&pdev->dev, "failed to enable the peripheral clock\n");
+ goto exit;
+ }
+
+ /* Request the IRQ */
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0) {
+ dev_err(&pdev->dev, "missing IRQ\n");
+ err = irq;
+ goto disable_clk;
+ }
+ err = devm_request_irq(&pdev->dev, irq, atmel_qspi_interrupt,
+ 0, dev_name(&pdev->dev), aq);
+ if (err)
+ goto disable_clk;
+
+ err = atmel_qspi_init(aq);
+ if (err)
+ goto disable_clk;
+
+ err = spi_register_controller(ctrl);
+ if (err)
+ goto disable_clk;
+
+ return 0;
+
+disable_clk:
+ clk_disable_unprepare(aq->clk);
+exit:
+ spi_controller_put(ctrl);
+
+ return err;
+}
+
+static int atmel_qspi_remove(struct platform_device *pdev)
+{
+ struct spi_controller *ctrl = platform_get_drvdata(pdev);
+ struct atmel_qspi *aq = spi_controller_get_devdata(ctrl);
+
+ spi_unregister_controller(ctrl);
+ qspi_writel(aq, QSPI_CR, QSPI_CR_QSPIDIS);
+ clk_disable_unprepare(aq->clk);
+ return 0;
+}
+
+static int __maybe_unused atmel_qspi_suspend(struct device *dev)
+{
+ struct atmel_qspi *aq = dev_get_drvdata(dev);
+
+ clk_disable_unprepare(aq->clk);
+
+ return 0;
+}
+
+static int __maybe_unused atmel_qspi_resume(struct device *dev)
+{
+ struct atmel_qspi *aq = dev_get_drvdata(dev);
+
+ clk_prepare_enable(aq->clk);
+
+ return atmel_qspi_init(aq);
+}
+
+static SIMPLE_DEV_PM_OPS(atmel_qspi_pm_ops, atmel_qspi_suspend,
+ atmel_qspi_resume);
+
+static const struct of_device_id atmel_qspi_dt_ids[] = {
+ { .compatible = "atmel,sama5d2-qspi" },
+ { /* sentinel */ }
+};
+
+MODULE_DEVICE_TABLE(of, atmel_qspi_dt_ids);
+
+static struct platform_driver atmel_qspi_driver = {
+ .driver = {
+ .name = "atmel_qspi",
+ .of_match_table = atmel_qspi_dt_ids,
+ .pm = &atmel_qspi_pm_ops,
+ },
+ .probe = atmel_qspi_probe,
+ .remove = atmel_qspi_remove,
+};
+module_platform_driver(atmel_qspi_driver);
+
+MODULE_AUTHOR("Cyrille Pitchen <cyrille.pitchen@atmel.com>");
+MODULE_AUTHOR("Piotr Bugalski <bugalski.piotr@gmail.com");
+MODULE_DESCRIPTION("Atmel QSPI Controller driver");
+MODULE_LICENSE("GPL v2");
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-23 14:42:50 +0000