spi: Add Atmel QuadSPI driver
Backport the driver from linux v5.1-rc5 and adapt it for u-boot.
Tested on sama5d2_xplained Rev B with mx25l25635e spi-nor flash.
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Jagan Teki <jagan@amarulasolutions.com>
diff --git a/drivers/spi/atmel-quadspi.c b/drivers/spi/atmel-quadspi.c
new file mode 100644
index 0000000..7d9a540
--- /dev/null
+++ b/drivers/spi/atmel-quadspi.c
@@ -0,0 +1,536 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * 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>
+ */
+
+#include <asm/io.h>
+#include <clk.h>
+#include <common.h>
+#include <dm.h>
+#include <errno.h>
+#include <fdtdec.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/ioport.h>
+#include <mach/clk.h>
+#include <spi.h>
+#include <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_WICR 0x0034 /* Write Instruction Code Register */
+#define QSPI_IFR 0x0038 /* Instruction Frame Register */
+#define QSPI_RICR 0x003C /* Read Instruction Code 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 (Read/Write 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_MEM BIT(12)
+#define QSPI_IFR_SAMA5D2_WRITE_TRSFR BIT(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)
+#define QSPI_IFR_APBTFRTYP_READ BIT(24) /* Defined in SAM9X60 */
+
+/* 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_caps {
+ bool has_qspick;
+ bool has_ricr;
+};
+
+struct atmel_qspi {
+ void __iomem *regs;
+ void __iomem *mem;
+ const struct atmel_qspi_caps *caps;
+ ulong bus_clk_rate;
+ u32 mr;
+};
+
+struct atmel_qspi_mode {
+ u8 cmd_buswidth;
+ u8 addr_buswidth;
+ u8 data_buswidth;
+ u32 config;
+};
+
+static const struct atmel_qspi_mode atmel_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 },
+};
+
+static inline bool atmel_qspi_is_compatible(const struct spi_mem_op *op,
+ const struct atmel_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 atmel_qspi_find_mode(const struct spi_mem_op *op)
+{
+ u32 i;
+
+ for (i = 0; i < ARRAY_SIZE(atmel_qspi_modes); i++)
+ if (atmel_qspi_is_compatible(op, &atmel_qspi_modes[i]))
+ return i;
+
+ return -ENOTSUPP;
+}
+
+static bool atmel_qspi_supports_op(struct spi_slave *slave,
+ const struct spi_mem_op *op)
+{
+ if (atmel_qspi_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_set_cfg(struct atmel_qspi *aq,
+ const struct spi_mem_op *op, u32 *offset)
+{
+ u32 iar, icr, ifr;
+ u32 dummy_cycles = 0;
+ int mode;
+
+ iar = 0;
+ icr = QSPI_ICR_INST(op->cmd.opcode);
+ ifr = QSPI_IFR_INSTEN;
+
+ mode = atmel_qspi_find_mode(op);
+ if (mode < 0)
+ return mode;
+ ifr |= atmel_qspi_modes[mode].config;
+
+ if (op->dummy.buswidth && op->dummy.nbytes)
+ dummy_cycles = op->dummy.nbytes * 8 / op->dummy.buswidth;
+
+ /*
+ * The controller allows 24 and 32-bit addressing while NAND-flash
+ * requires 16-bit long. Handling 8-bit long addresses is done using
+ * the option field. For the 16-bit addresses, the workaround depends
+ * of the number of requested dummy bits. If there are 8 or more dummy
+ * cycles, the address is shifted and sent with the first dummy byte.
+ * Otherwise opcode is disabled and the first byte of the address
+ * contains the command opcode (works only if the opcode and address
+ * use the same buswidth). The limitation is when the 16-bit address is
+ * used without enough dummy cycles and the opcode is using a different
+ * buswidth than the address.
+ */
+ 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;
+ }
+ }
+
+ /* offset of the data access in the QSPI memory space */
+ *offset = iar;
+
+ /* 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 the QSPI controller is set in regular SPI mode, set it in
+ * Serial Memory Mode (SMM).
+ */
+ if (aq->mr != QSPI_MR_SMM) {
+ writel(QSPI_MR_SMM, aq->regs + QSPI_MR);
+ aq->mr = QSPI_MR_SMM;
+ }
+
+ /* Clear pending interrupts */
+ (void)readl(aq->regs + QSPI_SR);
+
+ if (aq->caps->has_ricr) {
+ if (!op->addr.nbytes && op->data.dir == SPI_MEM_DATA_IN)
+ ifr |= QSPI_IFR_APBTFRTYP_READ;
+
+ /* Set QSPI Instruction Frame registers */
+ writel(iar, aq->regs + QSPI_IAR);
+ if (op->data.dir == SPI_MEM_DATA_IN)
+ writel(icr, aq->regs + QSPI_RICR);
+ else
+ writel(icr, aq->regs + QSPI_WICR);
+ writel(ifr, aq->regs + QSPI_IFR);
+ } else {
+ if (op->data.dir == SPI_MEM_DATA_OUT)
+ ifr |= QSPI_IFR_SAMA5D2_WRITE_TRSFR;
+
+ /* Set QSPI Instruction Frame registers */
+ writel(iar, aq->regs + QSPI_IAR);
+ writel(icr, aq->regs + QSPI_ICR);
+ writel(ifr, aq->regs + QSPI_IFR);
+ }
+
+ return 0;
+}
+
+static int atmel_qspi_exec_op(struct spi_slave *slave,
+ const struct spi_mem_op *op)
+{
+ struct atmel_qspi *aq = dev_get_priv(slave->dev->parent);
+ u32 sr, imr, offset;
+ int err;
+
+ err = atmel_qspi_set_cfg(aq, op, &offset);
+ if (err)
+ return err;
+
+ /* 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)readl(aq->regs + QSPI_IFR);
+
+ /* Send/Receive data */
+ if (op->data.dir == SPI_MEM_DATA_IN)
+ memcpy_fromio(op->data.buf.in, aq->mem + offset,
+ op->data.nbytes);
+ else
+ memcpy_toio(aq->mem + offset, op->data.buf.out,
+ op->data.nbytes);
+
+ /* Release the chip-select */
+ writel(QSPI_CR_LASTXFER, aq->regs + QSPI_CR);
+ }
+
+ /* Poll INSTruction End and Chip Select Rise flags. */
+ imr = QSPI_SR_INSTRE | QSPI_SR_CSR;
+ return readl_poll_timeout(aq->regs + QSPI_SR, sr, (sr & imr) == imr,
+ 1000000);
+}
+
+static int atmel_qspi_set_speed(struct udevice *bus, uint hz)
+{
+ struct atmel_qspi *aq = dev_get_priv(bus);
+ u32 scr, scbr, mask, new_value;
+
+ /* Compute the QSPI baudrate */
+ scbr = DIV_ROUND_UP(aq->bus_clk_rate, hz);
+ if (scbr > 0)
+ scbr--;
+
+ new_value = QSPI_SCR_SCBR(scbr);
+ mask = QSPI_SCR_SCBR_MASK;
+
+ scr = readl(aq->regs + QSPI_SCR);
+ if ((scr & mask) == new_value)
+ return 0;
+
+ scr = (scr & ~mask) | new_value;
+ writel(scr, aq->regs + QSPI_SCR);
+
+ return 0;
+}
+
+static int atmel_qspi_set_mode(struct udevice *bus, uint mode)
+{
+ struct atmel_qspi *aq = dev_get_priv(bus);
+ u32 scr, mask, new_value = 0;
+
+ if (mode & SPI_CPOL)
+ new_value = QSPI_SCR_CPOL;
+ if (mode & SPI_CPHA)
+ new_value = QSPI_SCR_CPHA;
+
+ mask = QSPI_SCR_CPOL | QSPI_SCR_CPHA;
+
+ scr = readl(aq->regs + QSPI_SCR);
+ if ((scr & mask) == new_value)
+ return 0;
+
+ scr = (scr & ~mask) | new_value;
+ writel(scr, aq->regs + QSPI_SCR);
+
+ return 0;
+}
+
+static int atmel_qspi_enable_clk(struct udevice *dev)
+{
+ struct atmel_qspi *aq = dev_get_priv(dev);
+ struct clk pclk, qspick;
+ int ret;
+
+ ret = clk_get_by_name(dev, "pclk", &pclk);
+ if (ret)
+ ret = clk_get_by_index(dev, 0, &pclk);
+
+ if (ret) {
+ dev_err(dev, "Missing QSPI peripheral clock\n");
+ return ret;
+ }
+
+ ret = clk_enable(&pclk);
+ if (ret) {
+ dev_err(dev, "Failed to enable QSPI peripheral clock\n");
+ goto free_pclk;
+ }
+
+ if (aq->caps->has_qspick) {
+ /* Get the QSPI system clock */
+ ret = clk_get_by_name(dev, "qspick", &qspick);
+ if (ret) {
+ dev_err(dev, "Missing QSPI peripheral clock\n");
+ goto free_pclk;
+ }
+
+ ret = clk_enable(&qspick);
+ if (ret)
+ dev_err(dev, "Failed to enable QSPI system clock\n");
+ clk_free(&qspick);
+ }
+
+ aq->bus_clk_rate = clk_get_rate(&pclk);
+ if (!aq->bus_clk_rate)
+ ret = -EINVAL;
+
+free_pclk:
+ clk_free(&pclk);
+
+ return ret;
+}
+
+static void atmel_qspi_init(struct atmel_qspi *aq)
+{
+ /* Reset the QSPI controller */
+ writel(QSPI_CR_SWRST, aq->regs + QSPI_CR);
+
+ /* Set the QSPI controller by default in Serial Memory Mode */
+ writel(QSPI_MR_SMM, aq->regs + QSPI_MR);
+ aq->mr = QSPI_MR_SMM;
+
+ /* Enable the QSPI controller */
+ writel(QSPI_CR_QSPIEN, aq->regs + QSPI_CR);
+}
+
+static int atmel_qspi_probe(struct udevice *dev)
+{
+ struct atmel_qspi *aq = dev_get_priv(dev);
+ struct resource res;
+ int ret;
+
+ aq->caps = (struct atmel_qspi_caps *)dev_get_driver_data(dev);
+ if (!aq->caps) {
+ dev_err(dev, "Could not retrieve QSPI caps\n");
+ return -EINVAL;
+ };
+
+ /* Map the registers */
+ ret = dev_read_resource_byname(dev, "qspi_base", &res);
+ if (ret) {
+ dev_err(dev, "missing registers\n");
+ return ret;
+ }
+
+ aq->regs = devm_ioremap(dev, res.start, resource_size(&res));
+ if (IS_ERR(aq->regs))
+ return PTR_ERR(aq->regs);
+
+ /* Map the AHB memory */
+ ret = dev_read_resource_byname(dev, "qspi_mmap", &res);
+ if (ret) {
+ dev_err(dev, "missing AHB memory\n");
+ return ret;
+ }
+
+ aq->mem = devm_ioremap(dev, res.start, resource_size(&res));
+ if (IS_ERR(aq->mem))
+ return PTR_ERR(aq->mem);
+
+ ret = atmel_qspi_enable_clk(dev);
+ if (ret)
+ return ret;
+
+ atmel_qspi_init(aq);
+
+ return 0;
+}
+
+static const struct spi_controller_mem_ops atmel_qspi_mem_ops = {
+ .supports_op = atmel_qspi_supports_op,
+ .exec_op = atmel_qspi_exec_op,
+};
+
+static const struct dm_spi_ops atmel_qspi_ops = {
+ .set_speed = atmel_qspi_set_speed,
+ .set_mode = atmel_qspi_set_mode,
+ .mem_ops = &atmel_qspi_mem_ops,
+};
+
+static const struct atmel_qspi_caps atmel_sama5d2_qspi_caps = {};
+
+static const struct atmel_qspi_caps atmel_sam9x60_qspi_caps = {
+ .has_qspick = true,
+ .has_ricr = true,
+};
+
+static const struct udevice_id atmel_qspi_ids[] = {
+ {
+ .compatible = "atmel,sama5d2-qspi",
+ .data = (ulong)&atmel_sama5d2_qspi_caps,
+ },
+ {
+ .compatible = "microchip,sam9x60-qspi",
+ .data = (ulong)&atmel_sam9x60_qspi_caps,
+ },
+ { /* sentinel */ }
+};
+
+U_BOOT_DRIVER(atmel_qspi) = {
+ .name = "atmel_qspi",
+ .id = UCLASS_SPI,
+ .of_match = atmel_qspi_ids,
+ .ops = &atmel_qspi_ops,
+ .priv_auto_alloc_size = sizeof(struct atmel_qspi),
+ .probe = atmel_qspi_probe,
+};