soc/mediatek/mt8192: Use SPI-NOR as flash controller

Add a SPI-NOR flash controller which supports pio mode.

Signed-off-by: CK Hu <ck.hu@mediatek.com>
Change-Id: I1e38672a532dd8234b3ef24c84113888c8795810
Reviewed-on: https://review.coreboot.org/c/coreboot/+/44453
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Hung-Te Lin <hungte@chromium.org>

src/soc/mediatek/mt8192/Makefile.inc

@@ -1,6 +1,7 @@
 ifeq ($(CONFIG_SOC_MEDIATEK_MT8192),y)
 
 bootblock-y += bootblock.c
+bootblock-y += flash_controller.c
 bootblock-y += ../common/gpio.c gpio.c
 bootblock-y += ../common/mmu_operations.c
 bootblock-$(CONFIG_SPI_FLASH) += ../common/spi.c spi.c
@@ -8,6 +9,7 @@ bootblock-y += ../common/timer.c
 bootblock-y += ../common/uart.c
 bootblock-y += ../common/wdt.c
 
+verstage-y += flash_controller.c
 verstage-y += ../common/gpio.c gpio.c
 verstage-$(CONFIG_SPI_FLASH) += ../common/spi.c spi.c
 verstage-y += ../common/timer.c
@@ -15,11 +17,13 @@ verstage-y += ../common/uart.c
 
 romstage-y += ../common/cbmem.c
 romstage-y += emi.c
+romstage-y += flash_controller.c
 romstage-y += ../common/gpio.c gpio.c
 romstage-$(CONFIG_SPI_FLASH) += ../common/spi.c spi.c
 romstage-y += ../common/timer.c
 romstage-y += ../common/uart.c
 
+ramstage-y += flash_controller.c
 ramstage-y += ../common/gpio.c gpio.c
 ramstage-y += emi.c
 ramstage-$(CONFIG_SPI_FLASH) += ../common/spi.c spi.c

src/soc/mediatek/mt8192/flash_controller.c

@@ -0,0 +1,172 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#include <assert.h>
+#include <console/console.h>
+#include <device/mmio.h>
+#include <soc/flash_controller.h>
+#include <spi_flash.h>
+#include <spi-generic.h>
+#include <stdint.h>
+#include <string.h>
+#include <timer.h>
+#include <types.h>
+
+#define GET_NTH_BYTE(d, n)	((d >> (8 * n)) & 0xff)
+
+static int polling_cmd(u32 val)
+{
+	struct stopwatch sw;
+
+	stopwatch_init_usecs_expire(&sw, SFLASH_POLLINGREG_US);
+
+	while ((read32(&mt8192_nor->cmd) & val) != 0) {
+		if (stopwatch_expired(&sw))
+			return -1;
+	}
+
+	return 0;
+}
+
+static int mt8192_nor_execute_cmd(u8 cmdval)
+{
+	u8 val = cmdval & ~SFLASH_AUTOINC;
+
+	write8(&mt8192_nor->cmd, cmdval);
+	return polling_cmd(val);
+}
+
+static int sflashhw_read_flash_status(u8 *value)
+{
+	if (mt8192_nor_execute_cmd(SFLASH_READSTATUS))
+		return -1;
+
+	*value = read8(&mt8192_nor->rdsr);
+	return 0;
+}
+
+static int wait_for_write_done(void)
+{
+	struct stopwatch sw;
+	u8 reg;
+
+	stopwatch_init_usecs_expire(&sw, SFLASH_POLLINGREG_US);
+
+	while (sflashhw_read_flash_status(&reg) == 0) {
+		if (!(reg & SFLASH_WRITE_IN_PROGRESS))
+			return 0;
+		if (stopwatch_expired(&sw))
+			return -1;
+	}
+
+	return -1;
+}
+
+/* set serial flash program address */
+static void set_sfpaddr(u32 addr)
+{
+	write8(&mt8192_nor->radr[2], GET_NTH_BYTE(addr, 2));
+	write8(&mt8192_nor->radr[1], GET_NTH_BYTE(addr, 1));
+	write8(&mt8192_nor->radr[0], GET_NTH_BYTE(addr, 0));
+}
+
+static int sector_erase(int offset)
+{
+	if (wait_for_write_done())
+		return -1;
+
+	write8(&mt8192_nor->prgdata[5], SFLASH_OP_WREN);
+	write8(&mt8192_nor->cnt, 8);
+	mt8192_nor_execute_cmd(SFLASH_PRG_CMD);
+
+	write8(&mt8192_nor->prgdata[5], SECTOR_ERASE_CMD);
+	write8(&mt8192_nor->prgdata[4], GET_NTH_BYTE(offset, 2));
+	write8(&mt8192_nor->prgdata[3], GET_NTH_BYTE(offset, 1));
+	write8(&mt8192_nor->prgdata[2], GET_NTH_BYTE(offset, 0));
+	write8(&mt8192_nor->cnt, 32);
+	mt8192_nor_execute_cmd(SFLASH_PRG_CMD);
+
+	if (wait_for_write_done())
+		return -1;
+
+	return 0;
+}
+
+static int pio_read(u32 addr, u8 *buf, u32 len)
+{
+	set_sfpaddr(addr);
+	while (len) {
+		if (mt8192_nor_execute_cmd(SFLASH_RD_TRIGGER | SFLASH_AUTOINC))
+			return -1;
+
+		*buf++ = read8(&mt8192_nor->rdata);
+		len--;
+	}
+	return 0;
+}
+
+static int nor_read(const struct spi_flash *flash, u32 addr, size_t len,
+		    void *buf)
+{
+	if (pio_read(addr, buf, len))
+		return -1;
+
+	return 0;
+}
+
+static int nor_write(const struct spi_flash *flash, u32 addr, size_t len,
+		     const void *buf)
+{
+	const u8 *buffer = (const u8 *)buf;
+
+	set_sfpaddr(addr);
+	while (len) {
+		write8(&mt8192_nor->wdata, *buffer);
+		if (mt8192_nor_execute_cmd(SFLASH_WR_TRIGGER | SFLASH_AUTOINC))
+			return -1;
+
+		if (wait_for_write_done())
+			return -1;
+		buffer++;
+		len--;
+	}
+	return 0;
+}
+
+static int nor_erase(const struct spi_flash *flash, u32 offset, size_t len)
+{
+	int sector_start = offset;
+	int sector_num = (u32)len / flash->sector_size;
+
+	while (sector_num) {
+		if (!sector_erase(sector_start)) {
+			sector_start += flash->sector_size;
+			sector_num--;
+		} else {
+			printk(BIOS_WARNING, "Erase failed at %#x!\n",
+			       sector_start);
+			return -1;
+		}
+	}
+	return 0;
+}
+
+const struct spi_flash_ops spi_flash_ops = {
+	.read = nor_read,
+	.write = nor_write,
+	.erase = nor_erase,
+};
+
+int mtk_spi_flash_probe(const struct spi_slave *spi,
+			struct spi_flash *flash)
+{
+	write32(&mt8192_nor->wrprot, SFLASH_COMMAND_ENABLE);
+	memcpy(&flash->spi, spi, sizeof(*spi));
+
+	flash->sector_size = 0x1000;
+	flash->erase_cmd = SECTOR_ERASE_CMD;
+	flash->size = CONFIG_ROM_SIZE;
+
+	flash->ops = &spi_flash_ops;
+
+	return 0;
+}

src/soc/mediatek/mt8192/include/soc/flash_controller.h

@@ -0,0 +1,78 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#ifndef __SOC_MEDIATEK_MT8192_FLASH_CONTROLLER_H__
+#define __SOC_MEDIATEK_MT8192_FLASH_CONTROLLER_H__
+
+#include <spi-generic.h>
+#include <stdint.h>
+#include <soc/addressmap.h>
+
+enum {
+	SFLASH_POLLINGREG_US	  = 500000,
+	SFLASH_WRBUF_SIZE	  = 128,
+	SFLASHNAME_LENGTH	  = 16,
+	SFLASH_WRITE_IN_PROGRESS  = 1,
+	SFLASH_COMMAND_ENABLE	  = 0x30,
+	SFLASH_DMA_ALIGN	  = 0x10,
+
+	/* NOR flash controller commands */
+	SFLASH_RD_TRIGGER	  = 1 << 0,
+	SFLASH_READSTATUS	  = 1 << 1,
+	SFLASH_PRG_CMD		  = 1 << 2,
+	SFLASH_WR_TRIGGER	  = 1 << 4,
+	SFLASH_WRITESTATUS	  = 1 << 5,
+	SFLASH_AUTOINC		  = 1 << 7,
+	/* NOR flash commands */
+	SFLASH_OP_WREN		  = 0x6,
+	SECTOR_ERASE_CMD	  = 0x20,
+	SFLASH_UNPROTECTED	  = 0x0,
+	/* DMA commands */
+	SFLASH_DMA_TRIGGER	  = 1 << 0,
+	SFLASH_DMA_SW_RESET	  = 1 << 1,
+	SFLASH_DMA_WDLE_EN	  = 1 << 2
+};
+
+/* register Offset */
+struct mt8192_nor_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 status[5];
+	u32 timing;
+	u32 flash_cfg;
+	u32 reserved2[3];
+	u32 sf_time;
+	u32 reserved3;
+	u32 diff_addr;
+	u32 del_sel[2];
+	u32 intrstus;
+	u32 intren;
+	u32 pp_ctl;
+	u32 cfg3;
+	u32 chksum_ctl;
+	u32 chksum;
+	u32 aaicmd;
+	u32 wrprot;
+	u32 radr3;
+	u32 read_dual;
+	u32 delsel[3];
+	u32 reserved[397];
+	u32 cfg1_bri[2];
+	u32 fdma_ctl;
+	u32 fdma_fadr;
+	u32 fdma_dadr;
+	u32 fdma_end_dadr;
+};
+check_member(mt8192_nor_regs, fdma_end_dadr, 0x724);
+static struct mt8192_nor_regs *const mt8192_nor = (void *)SFLASH_REG_BASE;
+
+int mtk_spi_flash_probe(const struct spi_slave *spi, struct spi_flash *flash);
+
+#endif /* __SOC_MEDIATEK_MT8192_FLASH_CONTROLLER_H__ */

src/soc/mediatek/mt8192/spi.c

@@ -3,6 +3,7 @@
 #include <device/mmio.h>
 #include <assert.h>
 #include <soc/addressmap.h>
+#include <soc/flash_controller.h>
 #include <soc/gpio.h>
 #include <soc/spi.h>
 
@@ -128,12 +129,22 @@ void mtk_spi_set_timing(struct mtk_spi_regs *regs, u32 sck_ticks, u32 cs_ticks,
 		     ((cs_ticks - 1) << SPI_CFG1_CS_IDLE_SHIFT));
 }
 
+static const struct spi_ctrlr spi_flash_ctrlr = {
+	.max_xfer_size = 65535,
+	.flash_probe = mtk_spi_flash_probe,
+};
+
 const struct spi_ctrlr_buses spi_ctrlr_bus_map[] = {
 	{
 		.ctrlr = &spi_ctrlr,
 		.bus_start = 0,
 		.bus_end = SPI_BUS_NUMBER - 1,
 	},
+	{
+		.ctrlr = &spi_flash_ctrlr,
+		.bus_start = CONFIG_BOOT_DEVICE_SPI_FLASH_BUS,
+		.bus_end = CONFIG_BOOT_DEVICE_SPI_FLASH_BUS,
+	},
 };
 
 const size_t spi_ctrlr_bus_map_count = ARRAY_SIZE(spi_ctrlr_bus_map);