spi: mtk_qspi: add qspi driver for MT7629 SoC
This patch adds MT7629 qspi driver for accessing SPI NOR flash.
Signed-off-by: Guochun Mao <guochun.mao@mediatek.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Jagan Teki <jagan@openedev.com>
diff --git a/drivers/spi/mtk_qspi.c b/drivers/spi/mtk_qspi.c
new file mode 100644
index 0000000..b510733
--- /dev/null
+++ b/drivers/spi/mtk_qspi.c
@@ -0,0 +1,359 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2018 MediaTek, Inc.
+ * Author : Guochun.Mao@mediatek.com
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <malloc.h>
+#include <spi.h>
+#include <asm/io.h>
+#include <linux/iopoll.h>
+#include <linux/ioport.h>
+
+/* Register Offset */
+struct mtk_qspi_regs {
+ u32 cmd;
+ u32 cnt;
+ u32 rdsr;
+ u32 rdata;
+ u32 radr[3];
+ u32 wdata;
+ u32 prgdata[6];
+ u32 shreg[10];
+ u32 cfg[2];
+ u32 shreg10;
+ u32 mode_mon;
+ u32 status[4];
+ u32 flash_time;
+ u32 flash_cfg;
+ u32 reserved_0[3];
+ u32 sf_time;
+ u32 pp_dw_data;
+ u32 reserved_1;
+ u32 delsel_0[2];
+ u32 intrstus;
+ u32 intren;
+ u32 reserved_2;
+ u32 cfg3;
+ u32 reserved_3;
+ u32 chksum;
+ u32 aaicmd;
+ u32 wrprot;
+ u32 radr3;
+ u32 dual;
+ u32 delsel_1[3];
+};
+
+struct mtk_qspi_platdata {
+ fdt_addr_t reg_base;
+ fdt_addr_t mem_base;
+};
+
+struct mtk_qspi_priv {
+ struct mtk_qspi_regs *regs;
+ unsigned long *mem_base;
+ u8 op;
+ u8 tx[3]; /* only record max 3 bytes paras, when it's address. */
+ u32 txlen; /* dout buffer length - op code length */
+ u8 *rx;
+ u32 rxlen;
+};
+
+#define MTK_QSPI_CMD_POLLINGREG_US 500000
+#define MTK_QSPI_WRBUF_SIZE 256
+#define MTK_QSPI_COMMAND_ENABLE 0x30
+
+/* NOR flash controller commands */
+#define MTK_QSPI_RD_TRIGGER BIT(0)
+#define MTK_QSPI_READSTATUS BIT(1)
+#define MTK_QSPI_PRG_CMD BIT(2)
+#define MTK_QSPI_WR_TRIGGER BIT(4)
+#define MTK_QSPI_WRITESTATUS BIT(5)
+#define MTK_QSPI_AUTOINC BIT(7)
+
+#define MTK_QSPI_MAX_RX_TX_SHIFT 0x6
+#define MTK_QSPI_MAX_SHIFT 0x8
+
+#define MTK_QSPI_WR_BUF_ENABLE 0x1
+#define MTK_QSPI_WR_BUF_DISABLE 0x0
+
+static int mtk_qspi_execute_cmd(struct mtk_qspi_priv *priv, u8 cmd)
+{
+ u8 tmp;
+ u8 val = cmd & ~MTK_QSPI_AUTOINC;
+
+ writeb(cmd, &priv->regs->cmd);
+
+ return readb_poll_timeout(&priv->regs->cmd, tmp, !(val & tmp),
+ MTK_QSPI_CMD_POLLINGREG_US);
+}
+
+static int mtk_qspi_tx_rx(struct mtk_qspi_priv *priv)
+{
+ int len = 1 + priv->txlen + priv->rxlen;
+ int i, ret, idx;
+
+ if (len > MTK_QSPI_MAX_SHIFT)
+ return -ERR_INVAL;
+
+ writeb(len * 8, &priv->regs->cnt);
+
+ /* start at PRGDATA5, go down to PRGDATA0 */
+ idx = MTK_QSPI_MAX_RX_TX_SHIFT - 1;
+
+ /* opcode */
+ writeb(priv->op, &priv->regs->prgdata[idx]);
+ idx--;
+
+ /* program TX data */
+ for (i = 0; i < priv->txlen; i++, idx--)
+ writeb(priv->tx[i], &priv->regs->prgdata[idx]);
+
+ /* clear out rest of TX registers */
+ while (idx >= 0) {
+ writeb(0, &priv->regs->prgdata[idx]);
+ idx--;
+ }
+
+ ret = mtk_qspi_execute_cmd(priv, MTK_QSPI_PRG_CMD);
+ if (ret)
+ return ret;
+
+ /* restart at first RX byte */
+ idx = priv->rxlen - 1;
+
+ /* read out RX data */
+ for (i = 0; i < priv->rxlen; i++, idx--)
+ priv->rx[i] = readb(&priv->regs->shreg[idx]);
+
+ return 0;
+}
+
+static int mtk_qspi_read(struct mtk_qspi_priv *priv,
+ u32 addr, u8 *buf, u32 len)
+{
+ memcpy(buf, (u8 *)priv->mem_base + addr, len);
+ return 0;
+}
+
+static void mtk_qspi_set_addr(struct mtk_qspi_priv *priv, u32 addr)
+{
+ int i;
+
+ for (i = 0; i < 3; i++) {
+ writeb(addr & 0xff, &priv->regs->radr[i]);
+ addr >>= 8;
+ }
+}
+
+static int mtk_qspi_write_single_byte(struct mtk_qspi_priv *priv,
+ u32 addr, u32 length, const u8 *data)
+{
+ int i, ret;
+
+ mtk_qspi_set_addr(priv, addr);
+
+ for (i = 0; i < length; i++) {
+ writeb(*data++, &priv->regs->wdata);
+ ret = mtk_qspi_execute_cmd(priv, MTK_QSPI_WR_TRIGGER);
+ if (ret < 0)
+ return ret;
+ }
+ return 0;
+}
+
+static int mtk_qspi_write_buffer(struct mtk_qspi_priv *priv, u32 addr,
+ const u8 *buf)
+{
+ int i, data;
+
+ mtk_qspi_set_addr(priv, addr);
+
+ for (i = 0; i < MTK_QSPI_WRBUF_SIZE; i += 4) {
+ data = buf[i + 3] << 24 | buf[i + 2] << 16 |
+ buf[i + 1] << 8 | buf[i];
+ writel(data, &priv->regs->pp_dw_data);
+ }
+
+ return mtk_qspi_execute_cmd(priv, MTK_QSPI_WR_TRIGGER);
+}
+
+static int mtk_qspi_write(struct mtk_qspi_priv *priv,
+ u32 addr, const u8 *buf, u32 len)
+{
+ int ret;
+
+ /* setting pre-fetch buffer for page program */
+ writel(MTK_QSPI_WR_BUF_ENABLE, &priv->regs->cfg[1]);
+ while (len >= MTK_QSPI_WRBUF_SIZE) {
+ ret = mtk_qspi_write_buffer(priv, addr, buf);
+ if (ret < 0)
+ return ret;
+
+ len -= MTK_QSPI_WRBUF_SIZE;
+ addr += MTK_QSPI_WRBUF_SIZE;
+ buf += MTK_QSPI_WRBUF_SIZE;
+ }
+ /* disable pre-fetch buffer for page program */
+ writel(MTK_QSPI_WR_BUF_DISABLE, &priv->regs->cfg[1]);
+
+ if (len)
+ return mtk_qspi_write_single_byte(priv, addr, len, buf);
+
+ return 0;
+}
+
+static int mtk_qspi_claim_bus(struct udevice *dev)
+{
+ /* nothing to do */
+ return 0;
+}
+
+static int mtk_qspi_release_bus(struct udevice *dev)
+{
+ /* nothing to do */
+ return 0;
+}
+
+static int mtk_qspi_transfer(struct mtk_qspi_priv *priv, unsigned int bitlen,
+ const void *dout, void *din, unsigned long flags)
+{
+ u32 bytes = DIV_ROUND_UP(bitlen, 8);
+ u32 addr;
+
+ if (!bytes)
+ return -ERR_INVAL;
+
+ if (dout) {
+ if (flags & SPI_XFER_BEGIN) {
+ /* parse op code and potential paras first */
+ priv->op = *(u8 *)dout;
+ if (bytes > 1)
+ memcpy(priv->tx, (u8 *)dout + 1,
+ bytes <= 4 ? bytes - 1 : 3);
+ priv->txlen = bytes - 1;
+ }
+
+ if (flags == SPI_XFER_ONCE) {
+ /* operations without receiving or sending data.
+ * for example: erase, write flash register or write
+ * enable...
+ */
+ priv->rx = NULL;
+ priv->rxlen = 0;
+ return mtk_qspi_tx_rx(priv);
+ }
+
+ if (flags & SPI_XFER_END) {
+ /* here, dout should be data to be written.
+ * and priv->tx should be filled 3Bytes address.
+ */
+ addr = priv->tx[0] << 16 | priv->tx[1] << 8 |
+ priv->tx[2];
+ return mtk_qspi_write(priv, addr, (u8 *)dout, bytes);
+ }
+ }
+
+ if (din) {
+ if (priv->txlen >= 3) {
+ /* if run to here, priv->tx[] should be the address
+ * where read data from,
+ * and, din is the buf to receive data.
+ */
+ addr = priv->tx[0] << 16 | priv->tx[1] << 8 |
+ priv->tx[2];
+ return mtk_qspi_read(priv, addr, (u8 *)din, bytes);
+ }
+
+ /* should be reading flash's register */
+ priv->rx = (u8 *)din;
+ priv->rxlen = bytes;
+ return mtk_qspi_tx_rx(priv);
+ }
+
+ return 0;
+}
+
+static int mtk_qspi_xfer(struct udevice *dev, unsigned int bitlen,
+ const void *dout, void *din, unsigned long flags)
+{
+ struct udevice *bus = dev->parent;
+ struct mtk_qspi_priv *priv = dev_get_priv(bus);
+
+ return mtk_qspi_transfer(priv, bitlen, dout, din, flags);
+}
+
+static int mtk_qspi_set_speed(struct udevice *bus, uint speed)
+{
+ /* nothing to do */
+ return 0;
+}
+
+static int mtk_qspi_set_mode(struct udevice *bus, uint mode)
+{
+ /* nothing to do */
+ return 0;
+}
+
+static int mtk_qspi_ofdata_to_platdata(struct udevice *bus)
+{
+ struct resource res_reg, res_mem;
+ struct mtk_qspi_platdata *plat = bus->platdata;
+ int ret;
+
+ ret = dev_read_resource_byname(bus, "reg_base", &res_reg);
+ if (ret) {
+ debug("can't get reg_base resource(ret = %d)\n", ret);
+ return -ENOMEM;
+ }
+
+ ret = dev_read_resource_byname(bus, "mem_base", &res_mem);
+ if (ret) {
+ debug("can't get map_base resource(ret = %d)\n", ret);
+ return -ENOMEM;
+ }
+
+ plat->mem_base = res_mem.start;
+ plat->reg_base = res_reg.start;
+
+ return 0;
+}
+
+static int mtk_qspi_probe(struct udevice *bus)
+{
+ struct mtk_qspi_platdata *plat = dev_get_platdata(bus);
+ struct mtk_qspi_priv *priv = dev_get_priv(bus);
+
+ priv->regs = (struct mtk_qspi_regs *)plat->reg_base;
+ priv->mem_base = (unsigned long *)plat->mem_base;
+
+ writel(MTK_QSPI_COMMAND_ENABLE, &priv->regs->wrprot);
+
+ return 0;
+}
+
+static const struct dm_spi_ops mtk_qspi_ops = {
+ .claim_bus = mtk_qspi_claim_bus,
+ .release_bus = mtk_qspi_release_bus,
+ .xfer = mtk_qspi_xfer,
+ .set_speed = mtk_qspi_set_speed,
+ .set_mode = mtk_qspi_set_mode,
+};
+
+static const struct udevice_id mtk_qspi_ids[] = {
+ { .compatible = "mediatek,mt7629-qspi" },
+ { }
+};
+
+U_BOOT_DRIVER(mtk_qspi) = {
+ .name = "mtk_qspi",
+ .id = UCLASS_SPI,
+ .of_match = mtk_qspi_ids,
+ .ops = &mtk_qspi_ops,
+ .ofdata_to_platdata = mtk_qspi_ofdata_to_platdata,
+ .platdata_auto_alloc_size = sizeof(struct mtk_qspi_platdata),
+ .priv_auto_alloc_size = sizeof(struct mtk_qspi_priv),
+ .probe = mtk_qspi_probe,
+};