--- /dev/null
+/*
+ * Copyright (C) 2014 Panasonic Corporation
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <common.h>
+#include <asm/io.h>
+#include <asm/unaligned.h>
+#include <linux/mtd/nand.h>
+#include "denali.h"
+
+#define SPARE_ACCESS 0x41
+#define MAIN_ACCESS 0x42
+#define PIPELINE_ACCESS 0x2000
+
+#define BANK(x) ((x) << 24)
+
+static void __iomem *denali_flash_mem =
+ (void __iomem *)CONFIG_SYS_NAND_DATA_BASE;
+static void __iomem *denali_flash_reg =
+ (void __iomem *)CONFIG_SYS_NAND_REGS_BASE;
+
+static const int flash_bank;
+static uint8_t page_buffer[NAND_MAX_PAGESIZE];
+static int page_size, oob_size, pages_per_block;
+
+static void index_addr(uint32_t address, uint32_t data)
+{
+ writel(address, denali_flash_mem + INDEX_CTRL_REG);
+ writel(data, denali_flash_mem + INDEX_DATA_REG);
+}
+
+static int wait_for_irq(uint32_t irq_mask)
+{
+ unsigned long timeout = 1000000;
+ uint32_t intr_status;
+
+ do {
+ intr_status = readl(denali_flash_reg + INTR_STATUS(flash_bank));
+
+ if (intr_status & INTR_STATUS__ECC_UNCOR_ERR) {
+ debug("Uncorrected ECC detected\n");
+ return -EIO;
+ }
+
+ if (intr_status & irq_mask)
+ break;
+
+ udelay(1);
+ timeout--;
+ } while (timeout);
+
+ if (!timeout) {
+ debug("Timeout with interrupt status %08x\n", intr_status);
+ return -EIO;
+ }
+
+ return 0;
+}
+
+static void read_data_from_flash_mem(uint8_t *buf, int len)
+{
+ int i;
+ uint32_t *buf32;
+
+ /* transfer the data from the flash */
+ buf32 = (uint32_t *)buf;
+
+ /*
+ * Let's take care of unaligned access although it rarely happens.
+ * Avoid put_unaligned() for the normal use cases since it leads to
+ * a bit performance regression.
+ */
+ if ((unsigned long)buf32 % 4) {
+ for (i = 0; i < len / 4; i++)
+ put_unaligned(readl(denali_flash_mem + INDEX_DATA_REG),
+ buf32++);
+ } else {
+ for (i = 0; i < len / 4; i++)
+ *buf32++ = readl(denali_flash_mem + INDEX_DATA_REG);
+ }
+
+ if (len % 4) {
+ u32 tmp;
+
+ tmp = cpu_to_le32(readl(denali_flash_mem + INDEX_DATA_REG));
+ buf = (uint8_t *)buf32;
+ for (i = 0; i < len % 4; i++) {
+ *buf++ = tmp;
+ tmp >>= 8;
+ }
+ }
+}
+
+int denali_send_pipeline_cmd(int page, int ecc_en, int access_type)
+{
+ uint32_t addr, cmd;
+ static uint32_t page_count = 1;
+
+ writel(ecc_en, denali_flash_reg + ECC_ENABLE);
+
+ /* clear all bits of intr_status. */
+ writel(0xffff, denali_flash_reg + INTR_STATUS(flash_bank));
+
+ addr = BANK(flash_bank) | page;
+
+ /* setup the acccess type */
+ cmd = MODE_10 | addr;
+ index_addr(cmd, access_type);
+
+ /* setup the pipeline command */
+ index_addr(cmd, PIPELINE_ACCESS | page_count);
+
+ cmd = MODE_01 | addr;
+ writel(cmd, denali_flash_mem + INDEX_CTRL_REG);
+
+ return wait_for_irq(INTR_STATUS__LOAD_COMP);
+}
+
+static int nand_read_oob(void *buf, int page)
+{
+ int ret;
+
+ ret = denali_send_pipeline_cmd(page, 0, SPARE_ACCESS);
+ if (ret < 0)
+ return ret;
+
+ read_data_from_flash_mem(buf, oob_size);
+
+ return 0;
+}
+
+static int nand_read_page(void *buf, int page)
+{
+ int ret;
+
+ ret = denali_send_pipeline_cmd(page, 1, MAIN_ACCESS);
+ if (ret < 0)
+ return ret;
+
+ read_data_from_flash_mem(buf, page_size);
+
+ return 0;
+}
+
+static int nand_block_isbad(int block)
+{
+ int ret;
+
+ ret = nand_read_oob(page_buffer, block * pages_per_block);
+ if (ret < 0)
+ return ret;
+
+ return page_buffer[CONFIG_SYS_NAND_BAD_BLOCK_POS] != 0xff;
+}
+
+/* nand_init() - initialize data to make nand usable by SPL */
+void nand_init(void)
+{
+ /* access to main area */
+ writel(0, denali_flash_reg + TRANSFER_SPARE_REG);
+
+ /*
+ * These registers are expected to be already set by the hardware
+ * or earlier boot code. So we read these values out.
+ */
+ page_size = readl(denali_flash_reg + DEVICE_MAIN_AREA_SIZE);
+ oob_size = readl(denali_flash_reg + DEVICE_SPARE_AREA_SIZE);
+ pages_per_block = readl(denali_flash_reg + PAGES_PER_BLOCK);
+}
+
+int nand_spl_load_image(uint32_t offs, unsigned int size, void *dst)
+{
+ int block, page, column, readlen;
+ int ret;
+ int force_bad_block_check = 1;
+
+ page = offs / page_size;
+ column = offs % page_size;
+
+ block = page / pages_per_block;
+ page = page % pages_per_block;
+
+ while (size) {
+ if (force_bad_block_check || page == 0) {
+ ret = nand_block_isbad(block);
+ if (ret < 0)
+ return ret;
+
+ if (ret) {
+ block++;
+ continue;
+ }
+ }
+
+ force_bad_block_check = 0;
+
+ if (unlikely(column || size < page_size)) {
+ /* Partial page read */
+ ret = nand_read_page(page_buffer,
+ block * pages_per_block + page);
+ if (ret < 0)
+ return ret;
+
+ readlen = min(page_size - column, size);
+ memcpy(dst, page_buffer, readlen);
+
+ column = 0;
+ } else {
+ ret = nand_read_page(dst,
+ block * pages_per_block + page);
+ if (ret < 0)
+ return ret;
+
+ readlen = page_size;
+ }
+
+ size -= readlen;
+ dst += readlen;
+ page++;
+ if (page == pages_per_block) {
+ block++;
+ page = 0;
+ }
+ }
+
+ return 0;
+}
+
+void nand_deselect(void) {}