--- /dev/null
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+
+/*
+ * Copyright (C) 2020 by Nuvoton Technology Corporation
+ * Mulin Chao <mlchao@nuvoton.com>
+ * Wealian Liao <WHLIAO@nuvoton.com>
+ */
+
+#include <stdint.h>
+#include <string.h>
+#include "npcx_flash.h"
+
+/*----------------------------------------------------------------------------
+ * NPCX flash driver
+ *----------------------------------------------------------------------------*/
+static void flash_execute_cmd(uint8_t code, uint8_t cts)
+{
+ /* Set UMA code */
+ NPCX_UMA_CODE = code;
+ /* Execute UMA flash transaction by CTS setting */
+ NPCX_UMA_CTS = cts;
+ /* Wait for transaction completed */
+ while (NPCX_IS_BIT_SET(NPCX_UMA_CTS, NPCX_UMA_CTS_EXEC_DONE))
+ ;
+}
+
+static void flash_cs_level(uint8_t level)
+{
+ /* Program chip select pin to high/low level */
+ if (level)
+ NPCX_SET_BIT(NPCX_UMA_ECTS, NPCX_UMA_ECTS_SW_CS1);
+ else
+ NPCX_CLEAR_BIT(NPCX_UMA_ECTS, NPCX_UMA_ECTS_SW_CS1);
+}
+
+static void flash_set_address(uint32_t dest_addr)
+{
+ uint8_t *addr = (uint8_t *)&dest_addr;
+
+ /* Set target flash address */
+ NPCX_UMA_AB2 = addr[2];
+ NPCX_UMA_AB1 = addr[1];
+ NPCX_UMA_AB0 = addr[0];
+}
+
+void delay(uint32_t i)
+{
+ while (i--)
+ ;
+}
+
+static int flash_wait_ready(uint32_t timeout)
+{
+ /* Chip Select down. -- Burst mode */
+ flash_cs_level(0);
+
+ /* Command for Read status register */
+ flash_execute_cmd(NPCX_CMD_READ_STATUS_REG, NPCX_MASK_CMD_ONLY);
+ while (timeout > 0) {
+ /* Read status register */
+ NPCX_UMA_CTS = NPCX_MASK_RD_1BYTE;
+ while (NPCX_IS_BIT_SET(NPCX_UMA_CTS, NPCX_UMA_CTS_EXEC_DONE))
+ ;
+
+ if (!(NPCX_UMA_DB0 & NPCX_SPI_FLASH_SR1_BUSY))
+ break;
+
+ if (--timeout > 0)
+ delay(100);
+
+ }; /* Wait for Busy clear */
+
+ /* Chip Select high. */
+ flash_cs_level(1);
+
+ if (timeout == 0)
+ return NPCX_FLASH_STATUS_FAILED_TIMEOUT;
+
+ return NPCX_FLASH_STATUS_OK;
+}
+
+static int flash_write_enable(void)
+{
+ /* Write enable command */
+ flash_execute_cmd(NPCX_CMD_WRITE_EN, NPCX_MASK_CMD_ONLY);
+
+ /* Wait for flash is not busy */
+ int status = flash_wait_ready(NPCX_FLASH_ABORT_TIMEOUT);
+ if (status != NPCX_FLASH_STATUS_OK)
+ return status;
+
+ if (NPCX_UMA_DB0 & NPCX_SPI_FLASH_SR1_WEL)
+ return NPCX_FLASH_STATUS_OK;
+ else
+ return NPCX_FLASH_STATUS_FAILED;
+}
+
+static void flash_burst_write(uint32_t dest_addr, uint16_t bytes,
+ const uint8_t *data)
+{
+ /* Chip Select down -- Burst mode */
+ flash_cs_level(0);
+
+ /* Set write address */
+ flash_set_address(dest_addr);
+ /* Start programming */
+ flash_execute_cmd(NPCX_CMD_FLASH_PROGRAM, NPCX_MASK_CMD_WR_ADR);
+ for (uint32_t i = 0; i < bytes; i++) {
+ flash_execute_cmd(*data, NPCX_MASK_CMD_WR_ONLY);
+ data++;
+ }
+
+ /* Chip Select up */
+ flash_cs_level(1);
+}
+
+/* The data to write cannot cross 256 Bytes boundary */
+static int flash_program_write(uint32_t addr, uint32_t size,
+ const uint8_t *data)
+{
+ int status = flash_write_enable();
+ if (status != NPCX_FLASH_STATUS_OK)
+ return status;
+
+ flash_burst_write(addr, size, data);
+ return flash_wait_ready(NPCX_FLASH_ABORT_TIMEOUT);
+}
+
+int flash_physical_write(uint32_t offset, uint32_t size, const uint8_t *data)
+{
+ int status;
+ uint32_t trunk_start = (offset + 0xff) & ~0xff;
+
+ /* write head */
+ uint32_t dest_addr = offset;
+ uint32_t write_len = ((trunk_start - offset) > size) ? size : (trunk_start - offset);
+
+ if (write_len) {
+ status = flash_program_write(dest_addr, write_len, data);
+ if (status != NPCX_FLASH_STATUS_OK)
+ return status;
+ data += write_len;
+ }
+
+ dest_addr = trunk_start;
+ size -= write_len;
+
+ /* write remaining data*/
+ while (size > 0) {
+ write_len = (size > NPCX_FLASH_WRITE_SIZE) ?
+ NPCX_FLASH_WRITE_SIZE : size;
+
+ status = flash_program_write(dest_addr, write_len, data);
+ if (status != NPCX_FLASH_STATUS_OK)
+ return status;
+
+ data += write_len;
+ dest_addr += write_len;
+ size -= write_len;
+ }
+
+ return NPCX_FLASH_STATUS_OK;
+}
+
+int flash_physical_erase(uint32_t offset, uint32_t size)
+{
+ /* Alignment has been checked in upper layer */
+ for (; size > 0; size -= NPCX_FLASH_ERASE_SIZE,
+ offset += NPCX_FLASH_ERASE_SIZE) {
+ /* Enable write */
+ int status = flash_write_enable();
+ if (status != NPCX_FLASH_STATUS_OK)
+ return status;
+
+ /* Set erase address */
+ flash_set_address(offset);
+ /* Start erase */
+ flash_execute_cmd(NPCX_CMD_SECTOR_ERASE, NPCX_MASK_CMD_ADR);
+ /* Wait erase completed */
+ status = flash_wait_ready(NPCX_FLASH_ABORT_TIMEOUT);
+ if (status != NPCX_FLASH_STATUS_OK)
+ return status;
+ }
+
+ return NPCX_FLASH_STATUS_OK;
+}
+
+int flash_physical_erase_all(void)
+{
+ /* Enable write */
+ int status = flash_write_enable();
+ if (status != NPCX_FLASH_STATUS_OK)
+ return status;
+
+ /* Start erase */
+ flash_execute_cmd(NPCX_CMD_CHIP_ERASE, NPCX_MASK_CMD_ONLY);
+
+ /* Wait erase completed */
+ status = flash_wait_ready(NPCX_FLASH_ABORT_TIMEOUT);
+ if (status != NPCX_FLASH_STATUS_OK)
+ return status;
+
+ return NPCX_FLASH_STATUS_OK;
+}
+
+int flash_physical_clear_stsreg(void)
+{
+ /* Enable write */
+ int status = flash_write_enable();
+ if (status != NPCX_FLASH_STATUS_OK)
+ return status;
+
+ NPCX_UMA_DB0 = 0x0;
+ NPCX_UMA_DB1 = 0x0;
+
+ /* Write status register 1/2 */
+ flash_execute_cmd(NPCX_CMD_WRITE_STATUS_REG, NPCX_MASK_CMD_WR_2BYTE);
+
+ /* Wait writing completed */
+ status = flash_wait_ready(NPCX_FLASH_ABORT_TIMEOUT);
+ if (status != NPCX_FLASH_STATUS_OK)
+ return status;
+
+ /* Read status register 1/2 for checking */
+ flash_execute_cmd(NPCX_CMD_READ_STATUS_REG, NPCX_MASK_CMD_RD_1BYTE);
+ if (NPCX_UMA_DB0 != 0x00)
+ return NPCX_FLASH_STATUS_FAILED;
+ flash_execute_cmd(NPCX_CMD_READ_STATUS_REG2, NPCX_MASK_CMD_RD_1BYTE);
+ if (NPCX_UMA_DB0 != 0x00)
+ return NPCX_FLASH_STATUS_FAILED;
+
+ return NPCX_FLASH_STATUS_OK;
+}
+
+int flash_get_id(uint32_t *id)
+{
+ flash_execute_cmd(NPCX_CMD_READ_ID, NPCX_MASK_CMD_RD_3BYTE);
+ *id = NPCX_UMA_DB0 << 16 | NPCX_UMA_DB1 << 8 | NPCX_UMA_DB2;
+
+ return NPCX_FLASH_STATUS_OK;
+}
+
+/*----------------------------------------------------------------------------
+ * flash loader function
+ *----------------------------------------------------------------------------*/
+uint32_t flashloader_init(struct npcx_flash_params *params)
+{
+ /* Initialize params buffers */
+ memset(params, 0, sizeof(struct npcx_flash_params));
+
+ return NPCX_FLASH_STATUS_OK;
+}
+
+/*----------------------------------------------------------------------------
+ * Functions
+ *----------------------------------------------------------------------------*/
+/* flashloader parameter structure */
+__attribute__ ((section(".buffers.g_cfg")))
+volatile struct npcx_flash_params g_cfg;
+/* data buffer */
+__attribute__ ((section(".buffers.g_buf")))
+uint8_t g_buf[NPCX_FLASH_LOADER_BUFFER_SIZE];
+
+int main(void)
+{
+ uint32_t id;
+
+ /* set buffer */
+ flashloader_init((struct npcx_flash_params *)&g_cfg);
+
+ /* Avoid F_CS0 toggles while programming the internal flash. */
+ NPCX_SET_BIT(NPCX_DEVALT(0), NPCX_DEVALT0_NO_F_SPI);
+
+ /* clear flash status registers */
+ int status = flash_physical_clear_stsreg();
+ if (status != NPCX_FLASH_STATUS_OK) {
+ while (1)
+ g_cfg.sync = status;
+ }
+
+ while (1) {
+ /* wait command*/
+ while (g_cfg.sync == NPCX_FLASH_LOADER_WAIT)
+ ;
+
+ /* command handler */
+ switch (g_cfg.cmd) {
+ case NPCX_FLASH_CMD_GET_FLASH_ID:
+ status = flash_get_id(&id);
+ if (status == NPCX_FLASH_STATUS_OK) {
+ g_buf[0] = id & 0xff;
+ g_buf[1] = (id >> 8) & 0xff;
+ g_buf[2] = (id >> 16) & 0xff;
+ g_buf[3] = 0x00;
+ }
+ break;
+ case NPCX_FLASH_CMD_ERASE_SECTORS:
+ status = flash_physical_erase(g_cfg.addr, g_cfg.len);
+ break;
+ case NPCX_FLASH_CMD_ERASE_ALL:
+ status = flash_physical_erase_all();
+ break;
+ case NPCX_FLASH_CMD_PROGRAM:
+ status = flash_physical_write(g_cfg.addr,
+ g_cfg.len,
+ g_buf);
+ break;
+ default:
+ status = NPCX_FLASH_STATUS_FAILED_UNKNOWN_COMMAND;
+ break;
+ }
+
+ /* clear & set result for next command */
+ if (status != NPCX_FLASH_STATUS_OK) {
+ g_cfg.sync = status;
+ while (1)
+ ;
+ } else {
+ g_cfg.sync = NPCX_FLASH_LOADER_WAIT;
+ }
+ }
+
+ return 0;
+}
+
+__attribute__ ((section(".stack")))
+__attribute__ ((used))
+static uint32_t stack[NPCX_FLASH_LOADER_STACK_SIZE / 4];
+extern uint32_t _estack;
+extern uint32_t _bss;
+extern uint32_t _ebss;
+
+__attribute__ ((section(".entry")))
+void entry(void)
+{
+ /* set sp from end of stack */
+ __asm(" ldr sp, =_estack - 4");
+
+ main();
+
+ __asm(" bkpt #0x00");
+}