--- /dev/null
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2019 MediaTek Inc. All Rights Reserved.
+ *
+ * Author: Weijie Gao <weijie.gao@mediatek.com>
+ */
+
+#include <common.h>
+#include <clk.h>
+#include <dm.h>
+#include <errno.h>
+#include <spi.h>
+#include <spi-mem.h>
+#include <stdbool.h>
+#include <watchdog.h>
+#include <dm/pinctrl.h>
+#include <linux/bitops.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+
+#define SNFI_MAC_CTL 0x500
+#define MAC_XIO_SEL BIT(4)
+#define SF_MAC_EN BIT(3)
+#define SF_TRIG BIT(2)
+#define WIP_READY BIT(1)
+#define WIP BIT(0)
+
+#define SNFI_MAC_OUTL 0x504
+#define SNFI_MAC_INL 0x508
+
+#define SNFI_MISC_CTL 0x538
+#define SW_RST BIT(28)
+#define FIFO_RD_LTC_SHIFT 25
+#define FIFO_RD_LTC GENMASK(26, 25)
+#define LATCH_LAT_SHIFT 8
+#define LATCH_LAT GENMASK(9, 8)
+#define CS_DESELECT_CYC_SHIFT 0
+#define CS_DESELECT_CYC GENMASK(4, 0)
+
+#define SNF_STA_CTL1 0x550
+#define SPI_STATE GENMASK(3, 0)
+
+#define SNFI_GPRAM_OFFSET 0x800
+#define SNFI_GPRAM_SIZE 0x80
+
+#define SNFI_POLL_INTERVAL 500000
+#define SNFI_RST_POLL_INTERVAL 1000000
+
+struct mtk_snfi_priv {
+ void __iomem *base;
+
+ struct clk nfi_clk;
+ struct clk pad_clk;
+};
+
+static int mtk_snfi_adjust_op_size(struct spi_slave *slave,
+ struct spi_mem_op *op)
+{
+ u32 nbytes;
+
+ /*
+ * When there is input data, it will be appended after the output
+ * data in the GPRAM. So the total size of either pure output data
+ * or the output+input data must not exceed the GPRAM size.
+ */
+
+ nbytes = sizeof(op->cmd.opcode) + op->addr.nbytes +
+ op->dummy.nbytes;
+
+ if (nbytes + op->data.nbytes <= SNFI_GPRAM_SIZE)
+ return 0;
+
+ if (nbytes >= SNFI_GPRAM_SIZE)
+ return -ENOTSUPP;
+
+ op->data.nbytes = SNFI_GPRAM_SIZE - nbytes;
+
+ return 0;
+}
+
+static bool mtk_snfi_supports_op(struct spi_slave *slave,
+ const struct spi_mem_op *op)
+{
+ if (op->cmd.buswidth > 1 || op->addr.buswidth > 1 ||
+ op->dummy.buswidth > 1 || op->data.buswidth > 1)
+ return false;
+
+ return true;
+}
+
+static int mtk_snfi_mac_trigger(struct mtk_snfi_priv *priv,
+ struct udevice *bus, u32 outlen, u32 inlen)
+{
+ int ret;
+ u32 val;
+
+#ifdef CONFIG_PINCTRL
+ pinctrl_select_state(bus, "snfi");
+#endif
+
+ writel(SF_MAC_EN, priv->base + SNFI_MAC_CTL);
+ writel(outlen, priv->base + SNFI_MAC_OUTL);
+ writel(inlen, priv->base + SNFI_MAC_INL);
+
+ writel(SF_MAC_EN | SF_TRIG, priv->base + SNFI_MAC_CTL);
+
+ ret = readl_poll_timeout(priv->base + SNFI_MAC_CTL, val,
+ val & WIP_READY, SNFI_POLL_INTERVAL);
+ if (ret) {
+ printf("%s: timed out waiting for WIP_READY\n", __func__);
+ goto cleanup;
+ }
+
+ ret = readl_poll_timeout(priv->base + SNFI_MAC_CTL, val,
+ !(val & WIP), SNFI_POLL_INTERVAL);
+ if (ret)
+ printf("%s: timed out waiting for WIP cleared\n", __func__);
+
+ writel(0, priv->base + SNFI_MAC_CTL);
+
+cleanup:
+#ifdef CONFIG_PINCTRL
+ pinctrl_select_state(bus, "default");
+#endif
+
+ return ret;
+}
+
+static int mtk_snfi_mac_reset(struct mtk_snfi_priv *priv)
+{
+ int ret;
+ u32 val;
+
+ setbits_32(priv->base + SNFI_MISC_CTL, SW_RST);
+
+ ret = readl_poll_timeout(priv->base + SNF_STA_CTL1, val,
+ !(val & SPI_STATE), SNFI_POLL_INTERVAL);
+ if (ret)
+ printf("%s: failed to reset snfi mac\n", __func__);
+
+ writel((2 << FIFO_RD_LTC_SHIFT) |
+ (10 << CS_DESELECT_CYC_SHIFT),
+ priv->base + SNFI_MISC_CTL);
+
+ return ret;
+}
+
+static void mtk_snfi_copy_to_gpram(struct mtk_snfi_priv *priv,
+ const void *data, size_t len)
+{
+ void __iomem *gpram = priv->base + SNFI_GPRAM_OFFSET;
+ size_t i, n = (len + sizeof(u32) - 1) / sizeof(u32);
+ const u32 *buff = data;
+
+ /*
+ * The output data will always be copied to the beginning of
+ * the GPRAM. Uses word write for better performace.
+ *
+ * Trailing bytes in the last word are not cared.
+ */
+
+ for (i = 0; i < n; i++)
+ writel(buff[i], gpram + i * sizeof(u32));
+}
+
+static void mtk_snfi_copy_from_gpram(struct mtk_snfi_priv *priv, u8 *cache,
+ void *data, size_t pos, size_t len)
+{
+ void __iomem *gpram = priv->base + SNFI_GPRAM_OFFSET;
+ u32 *buff = (u32 *)cache;
+ size_t i, off, end;
+
+ /* Start position in the buffer */
+ off = pos & (sizeof(u32) - 1);
+
+ /* End position for copy */
+ end = (len + pos + sizeof(u32) - 1) & (~(sizeof(u32) - 1));
+
+ /* Start position for copy */
+ pos &= ~(sizeof(u32) - 1);
+
+ /*
+ * Read aligned data from GPRAM to buffer first.
+ * Uses word read for better performace.
+ */
+ i = 0;
+ while (pos < end) {
+ buff[i++] = readl(gpram + pos);
+ pos += sizeof(u32);
+ }
+
+ /* Copy rx data */
+ memcpy(data, cache + off, len);
+}
+
+static int mtk_snfi_exec_op(struct spi_slave *slave,
+ const struct spi_mem_op *op)
+{
+ struct udevice *bus = dev_get_parent(slave->dev);
+ struct mtk_snfi_priv *priv = dev_get_priv(bus);
+ u8 gpram_cache[SNFI_GPRAM_SIZE];
+ u32 i, len = 0, inlen = 0;
+ int addr_sh;
+ int ret;
+
+ WATCHDOG_RESET();
+
+ ret = mtk_snfi_mac_reset(priv);
+ if (ret)
+ return ret;
+
+ /* Put opcode */
+ gpram_cache[len++] = op->cmd.opcode;
+
+ /* Put address */
+ addr_sh = (op->addr.nbytes - 1) * 8;
+ while (addr_sh >= 0) {
+ gpram_cache[len++] = (op->addr.val >> addr_sh) & 0xff;
+ addr_sh -= 8;
+ }
+
+ /* Put dummy bytes */
+ for (i = 0; i < op->dummy.nbytes; i++)
+ gpram_cache[len++] = 0;
+
+ /* Put output data */
+ if (op->data.nbytes && op->data.dir == SPI_MEM_DATA_OUT) {
+ memcpy(gpram_cache + len, op->data.buf.out, op->data.nbytes);
+ len += op->data.nbytes;
+ }
+
+ /* Copy final output data to GPRAM */
+ mtk_snfi_copy_to_gpram(priv, gpram_cache, len);
+
+ /* Start one SPI transaction */
+ if (op->data.nbytes && op->data.dir == SPI_MEM_DATA_IN)
+ inlen = op->data.nbytes;
+
+ ret = mtk_snfi_mac_trigger(priv, bus, len, inlen);
+ if (ret)
+ return ret;
+
+ /* Copy input data from GPRAM */
+ if (inlen)
+ mtk_snfi_copy_from_gpram(priv, gpram_cache, op->data.buf.in,
+ len, inlen);
+
+ return 0;
+}
+
+static int mtk_snfi_spi_probe(struct udevice *bus)
+{
+ struct mtk_snfi_priv *priv = dev_get_priv(bus);
+ int ret;
+
+ priv->base = (void __iomem *)devfdt_get_addr(bus);
+ if (!priv->base)
+ return -EINVAL;
+
+ ret = clk_get_by_name(bus, "nfi_clk", &priv->nfi_clk);
+ if (ret < 0)
+ return ret;
+
+ ret = clk_get_by_name(bus, "pad_clk", &priv->pad_clk);
+ if (ret < 0)
+ return ret;
+
+ clk_enable(&priv->nfi_clk);
+ clk_enable(&priv->pad_clk);
+
+ return 0;
+}
+
+static int mtk_snfi_set_speed(struct udevice *bus, uint speed)
+{
+ /*
+ * The SNFI does not have a bus clock divider.
+ * The bus clock is set in dts (pad_clk, UNIVPLL2_D8 = 50MHz).
+ */
+
+ return 0;
+}
+
+static int mtk_snfi_set_mode(struct udevice *bus, uint mode)
+{
+ /* The SNFI supports only mode 0 */
+
+ if (mode)
+ return -EINVAL;
+
+ return 0;
+}
+
+static const struct spi_controller_mem_ops mtk_snfi_mem_ops = {
+ .adjust_op_size = mtk_snfi_adjust_op_size,
+ .supports_op = mtk_snfi_supports_op,
+ .exec_op = mtk_snfi_exec_op,
+};
+
+static const struct dm_spi_ops mtk_snfi_spi_ops = {
+ .mem_ops = &mtk_snfi_mem_ops,
+ .set_speed = mtk_snfi_set_speed,
+ .set_mode = mtk_snfi_set_mode,
+};
+
+static const struct udevice_id mtk_snfi_spi_ids[] = {
+ { .compatible = "mediatek,mtk-snfi-spi" },
+ { }
+};
+
+U_BOOT_DRIVER(mtk_snfi_spi) = {
+ .name = "mtk_snfi_spi",
+ .id = UCLASS_SPI,
+ .of_match = mtk_snfi_spi_ids,
+ .ops = &mtk_snfi_spi_ops,
+ .priv_auto_alloc_size = sizeof(struct mtk_snfi_priv),
+ .probe = mtk_snfi_spi_probe,
+};