Add SPI-NAND framework

This framework supports SPI-NAND and is based on the
SPI-MEM framework for SPI operations. It uses a common high
level access using the io_mtd.

It is limited to the read functionalities.

Default behavior is the basic one data line operation
but it could be overridden by platform.

Change-Id: Icb4e0887c4003a826f47c876479dd004a323a32b
Signed-off-by: Lionel Debieve <lionel.debieve@st.com>
Signed-off-by: Christophe Kerello <christophe.kerello@st.com>
diff --git a/drivers/mtd/nand/spi_nand.c b/drivers/mtd/nand/spi_nand.c
new file mode 100644
index 0000000..d01a119
--- /dev/null
+++ b/drivers/mtd/nand/spi_nand.c
@@ -0,0 +1,320 @@
+/*
+ * Copyright (c) 2019,  STMicroelectronics - All Rights Reserved
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <assert.h>
+#include <errno.h>
+#include <stddef.h>
+
+#include <platform_def.h>
+
+#include <common/debug.h>
+#include <drivers/delay_timer.h>
+#include <drivers/spi_nand.h>
+#include <lib/utils.h>
+
+#define SPI_NAND_MAX_ID_LEN		4U
+#define DELAY_US_400MS			400000U
+#define MACRONIX_ID			0xC2U
+
+static struct spinand_device spinand_dev;
+
+#pragma weak plat_get_spi_nand_data
+int plat_get_spi_nand_data(struct spinand_device *device)
+{
+	return 0;
+}
+
+static int spi_nand_reg(bool read_reg, uint8_t reg, uint8_t *val,
+			enum spi_mem_data_dir dir)
+{
+	struct spi_mem_op op;
+
+	zeromem(&op, sizeof(struct spi_mem_op));
+	if (read_reg) {
+		op.cmd.opcode = SPI_NAND_OP_GET_FEATURE;
+	} else {
+		op.cmd.opcode = SPI_NAND_OP_SET_FEATURE;
+	}
+
+	op.cmd.buswidth = SPI_MEM_BUSWIDTH_1_LINE;
+	op.addr.val = reg;
+	op.addr.nbytes = 1U;
+	op.addr.buswidth = SPI_MEM_BUSWIDTH_1_LINE;
+	op.data.buswidth = SPI_MEM_BUSWIDTH_1_LINE;
+	op.data.dir = dir;
+	op.data.nbytes = 1U;
+	op.data.buf = val;
+
+	return spi_mem_exec_op(&op);
+}
+
+static int spi_nand_read_reg(uint8_t reg, uint8_t *val)
+{
+	return spi_nand_reg(true, reg, val, SPI_MEM_DATA_IN);
+}
+
+static int spi_nand_write_reg(uint8_t reg, uint8_t val)
+{
+	return spi_nand_reg(false, reg, &val, SPI_MEM_DATA_OUT);
+}
+
+static int spi_nand_update_cfg(uint8_t mask, uint8_t val)
+{
+	int ret;
+	uint8_t cfg = spinand_dev.cfg_cache;
+
+	cfg &= ~mask;
+	cfg |= val;
+
+	if (cfg == spinand_dev.cfg_cache) {
+		return 0;
+	}
+
+	ret = spi_nand_write_reg(SPI_NAND_REG_CFG, cfg);
+	if (ret == 0) {
+		spinand_dev.cfg_cache = cfg;
+	}
+
+	return ret;
+}
+
+static int spi_nand_ecc_enable(bool enable)
+{
+	return spi_nand_update_cfg(SPI_NAND_CFG_ECC_EN,
+				   enable ? SPI_NAND_CFG_ECC_EN : 0U);
+}
+
+static int spi_nand_quad_enable(uint8_t manufacturer_id)
+{
+	bool enable = false;
+
+	if (manufacturer_id != MACRONIX_ID) {
+		return 0;
+	}
+
+	if (spinand_dev.spi_read_cache_op.data.buswidth ==
+	    SPI_MEM_BUSWIDTH_4_LINE) {
+		enable = true;
+	}
+
+	return spi_nand_update_cfg(SPI_NAND_CFG_QE,
+				   enable ? SPI_NAND_CFG_QE : 0U);
+}
+
+static int spi_nand_wait_ready(uint8_t *status)
+{
+	int ret;
+	uint64_t timeout = timeout_init_us(DELAY_US_400MS);
+
+	while (!timeout_elapsed(timeout)) {
+		ret = spi_nand_read_reg(SPI_NAND_REG_STATUS, status);
+		if (ret != 0) {
+			return ret;
+		}
+
+		VERBOSE("%s Status %x\n", __func__, *status);
+		if ((*status & SPI_NAND_STATUS_BUSY) == 0U) {
+			return 0;
+		}
+	}
+
+	return -ETIMEDOUT;
+}
+
+static int spi_nand_reset(void)
+{
+	struct spi_mem_op op;
+	uint8_t status;
+	int ret;
+
+	zeromem(&op, sizeof(struct spi_mem_op));
+	op.cmd.opcode = SPI_NAND_OP_RESET;
+	op.cmd.buswidth = SPI_MEM_BUSWIDTH_1_LINE;
+
+	ret = spi_mem_exec_op(&op);
+	if (ret != 0) {
+		return ret;
+	}
+
+	return spi_nand_wait_ready(&status);
+}
+
+static int spi_nand_read_id(uint8_t *id)
+{
+	struct spi_mem_op op;
+
+	zeromem(&op, sizeof(struct spi_mem_op));
+	op.cmd.opcode = SPI_NAND_OP_READ_ID;
+	op.cmd.buswidth = SPI_MEM_BUSWIDTH_1_LINE;
+	op.data.dir = SPI_MEM_DATA_IN;
+	op.data.nbytes = SPI_NAND_MAX_ID_LEN;
+	op.data.buf = id;
+	op.data.buswidth = SPI_MEM_BUSWIDTH_1_LINE;
+
+	return spi_mem_exec_op(&op);
+}
+
+static int spi_nand_load_page(unsigned int page)
+{
+	struct spi_mem_op op;
+	uint32_t block_nb = page / spinand_dev.nand_dev->block_size;
+	uint32_t page_nb = page - (block_nb * spinand_dev.nand_dev->page_size);
+	uint32_t nbpages_per_block = spinand_dev.nand_dev->block_size /
+				     spinand_dev.nand_dev->page_size;
+	uint32_t block_sh = __builtin_ctz(nbpages_per_block) + 1U;
+
+	zeromem(&op, sizeof(struct spi_mem_op));
+	op.cmd.opcode = SPI_NAND_OP_LOAD_PAGE;
+	op.cmd.buswidth = SPI_MEM_BUSWIDTH_1_LINE;
+	op.addr.val = (block_nb << block_sh) | page_nb;
+	op.addr.nbytes = 3U;
+	op.addr.buswidth = SPI_MEM_BUSWIDTH_1_LINE;
+
+	return spi_mem_exec_op(&op);
+}
+
+static int spi_nand_read_from_cache(unsigned int page, unsigned int offset,
+				    uint8_t *buffer, unsigned int len)
+{
+	uint32_t nbpages_per_block = spinand_dev.nand_dev->block_size /
+				     spinand_dev.nand_dev->page_size;
+	uint32_t block_nb = page / nbpages_per_block;
+	uint32_t page_sh = __builtin_ctz(spinand_dev.nand_dev->page_size) + 1U;
+
+	spinand_dev.spi_read_cache_op.addr.val = offset;
+
+	if ((spinand_dev.nand_dev->nb_planes > 1U) && ((block_nb % 2U) == 1U)) {
+		spinand_dev.spi_read_cache_op.addr.val |= 1U << page_sh;
+	}
+
+	spinand_dev.spi_read_cache_op.data.buf = buffer;
+	spinand_dev.spi_read_cache_op.data.nbytes = len;
+
+	return spi_mem_exec_op(&spinand_dev.spi_read_cache_op);
+}
+
+static int spi_nand_read_page(unsigned int page, unsigned int offset,
+			      uint8_t *buffer, unsigned int len,
+			      bool ecc_enabled)
+{
+	uint8_t status;
+	int ret;
+
+	ret = spi_nand_ecc_enable(ecc_enabled);
+	if (ret != 0) {
+		return ret;
+	}
+
+	ret = spi_nand_load_page(page);
+	if (ret != 0) {
+		return ret;
+	}
+
+	ret = spi_nand_wait_ready(&status);
+	if (ret != 0) {
+		return ret;
+	}
+
+	ret = spi_nand_read_from_cache(page, offset, buffer, len);
+	if (ret != 0) {
+		return ret;
+	}
+
+	if (ecc_enabled && ((status & SPI_NAND_STATUS_ECC_UNCOR) != 0U)) {
+		return -EBADMSG;
+	}
+
+	return 0;
+}
+
+static int spi_nand_mtd_block_is_bad(unsigned int block)
+{
+	unsigned int nbpages_per_block = spinand_dev.nand_dev->block_size /
+					 spinand_dev.nand_dev->page_size;
+	uint8_t bbm_marker[2];
+	int ret;
+
+	ret = spi_nand_read_page(block * nbpages_per_block,
+				 spinand_dev.nand_dev->page_size,
+				 bbm_marker, sizeof(bbm_marker), false);
+	if (ret != 0) {
+		return ret;
+	}
+
+	if ((bbm_marker[0] != GENMASK_32(7, 0)) ||
+	    (bbm_marker[1] != GENMASK_32(7, 0))) {
+		WARN("Block %i is bad\n", block);
+		return 1;
+	}
+
+	return 0;
+}
+
+static int spi_nand_mtd_read_page(struct nand_device *nand, unsigned int page,
+				  uintptr_t buffer)
+{
+	return spi_nand_read_page(page, 0, (uint8_t *)buffer,
+				  spinand_dev.nand_dev->page_size, true);
+}
+
+int spi_nand_init(unsigned long long *size, unsigned int *erase_size)
+{
+	uint8_t id[SPI_NAND_MAX_ID_LEN];
+	int ret;
+
+	spinand_dev.nand_dev = get_nand_device();
+	if (spinand_dev.nand_dev == NULL) {
+		return -EINVAL;
+	}
+
+	spinand_dev.nand_dev->mtd_block_is_bad = spi_nand_mtd_block_is_bad;
+	spinand_dev.nand_dev->mtd_read_page = spi_nand_mtd_read_page;
+	spinand_dev.nand_dev->nb_planes = 1;
+
+	spinand_dev.spi_read_cache_op.cmd.opcode = SPI_NAND_OP_READ_FROM_CACHE;
+	spinand_dev.spi_read_cache_op.cmd.buswidth = SPI_MEM_BUSWIDTH_1_LINE;
+	spinand_dev.spi_read_cache_op.addr.nbytes = 2U;
+	spinand_dev.spi_read_cache_op.addr.buswidth = SPI_MEM_BUSWIDTH_1_LINE;
+	spinand_dev.spi_read_cache_op.dummy.nbytes = 1U;
+	spinand_dev.spi_read_cache_op.dummy.buswidth = SPI_MEM_BUSWIDTH_1_LINE;
+	spinand_dev.spi_read_cache_op.data.buswidth = SPI_MEM_BUSWIDTH_1_LINE;
+
+	if (plat_get_spi_nand_data(&spinand_dev) != 0) {
+		return -EINVAL;
+	}
+
+	ret = spi_nand_reset();
+	if (ret != 0) {
+		return ret;
+	}
+
+	ret = spi_nand_read_id(id);
+	if (ret != 0) {
+		return ret;
+	}
+
+	ret = spi_nand_read_reg(SPI_NAND_REG_CFG, &spinand_dev.cfg_cache);
+	if (ret != 0) {
+		return ret;
+	}
+
+	ret = spi_nand_quad_enable(id[0]);
+	if (ret != 0) {
+		return ret;
+	}
+
+	VERBOSE("SPI_NAND Detected ID 0x%x 0x%x\n", id[0], id[1]);
+
+	VERBOSE("Page size %i, Block size %i, size %lli\n",
+		spinand_dev.nand_dev->page_size,
+		spinand_dev.nand_dev->block_size,
+		spinand_dev.nand_dev->size);
+
+	*size = spinand_dev.nand_dev->size;
+	*erase_size = spinand_dev.nand_dev->block_size;
+
+	return 0;
+}