Add SPI flash driver

This driver is taken from u-boot and adapted to match
coreboot. It still contains some hacks and is ICH specific
at places.

Change-Id: I97dd8096f7db3b62f8f4f4e4d08bdee10d88f689
Signed-off-by: Patrick Georgi <patrick@georgi-clan.de>
Reviewed-on: http://review.coreboot.org/997
Tested-by: build bot (Jenkins)
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>

src/drivers/spi/eon.c

@@ -0,0 +1,161 @@
+/*
+ * (C) Copyright 2010, ucRobotics Inc.
+ * Author: Chong Huang <chuang@ucrobotics.com>
+ * Licensed under the GPL-2 or later.
+ */
+
+#include <stdlib.h>
+#include <spi_flash.h>
+#include "spi_flash_internal.h"
+
+/* EN25Q128-specific commands */
+#define CMD_EN25Q128_WREN	0x06    /* Write Enable */
+#define CMD_EN25Q128_WRDI	0x04    /* Write Disable */
+#define CMD_EN25Q128_RDSR	0x05    /* Read Status Register */
+#define CMD_EN25Q128_WRSR	0x01    /* Write Status Register */
+#define CMD_EN25Q128_READ	0x03    /* Read Data Bytes */
+#define CMD_EN25Q128_FAST_READ	0x0b    /* Read Data Bytes at Higher Speed */
+#define CMD_EN25Q128_PP		0x02    /* Page Program */
+#define CMD_EN25Q128_SE		0x20    /* Sector Erase */
+#define CMD_EN25Q128_BE		0xd8    /* Block Erase */
+#define CMD_EN25Q128_DP		0xb9    /* Deep Power-down */
+#define CMD_EN25Q128_RES	0xab    /* Release from DP, and Read Signature */
+
+#define EON_ID_EN25Q128		0x18
+
+struct eon_spi_flash_params {
+	u8 idcode1;
+	u16 page_size;
+	u16 pages_per_sector;
+	u16 sectors_per_block;
+	u16 nr_sectors;
+	const char *name;
+};
+
+/* spi_flash needs to be first so upper layers can free() it */
+struct eon_spi_flash {
+	struct spi_flash flash;
+	const struct eon_spi_flash_params *params;
+};
+
+static inline struct eon_spi_flash *to_eon_spi_flash(struct spi_flash *flash)
+{
+	return container_of(flash, struct eon_spi_flash, flash);
+}
+
+static const struct eon_spi_flash_params eon_spi_flash_table[] = {
+	{
+		.idcode1 = EON_ID_EN25Q128,
+		.page_size = 256,
+		.pages_per_sector = 16,
+		.sectors_per_block = 16,
+		.nr_sectors = 4096,
+		.name = "EN25Q128",
+	},
+};
+
+static int eon_write(struct spi_flash *flash,
+		     u32 offset, size_t len, const void *buf)
+{
+	struct eon_spi_flash *eon = to_eon_spi_flash(flash);
+	unsigned long page_addr;
+	unsigned long byte_addr;
+	unsigned long page_size;
+	size_t chunk_len;
+	size_t actual;
+	int ret;
+	u8 cmd[4];
+
+	page_size = eon->params->page_size;
+	page_addr = offset / page_size;
+	byte_addr = offset % page_size;
+
+	ret = spi_claim_bus(flash->spi);
+	if (ret) {
+		printk(BIOS_WARNING, "SF: Unable to claim SPI bus\n");
+		return ret;
+	}
+
+	ret = 0;
+	for (actual = 0; actual < len; actual += chunk_len) {
+		chunk_len = min(len - actual, page_size - byte_addr);
+
+		cmd[0] = CMD_EN25Q128_PP;
+		cmd[1] = page_addr >> 8;
+		cmd[2] = page_addr;
+		cmd[3] = byte_addr;
+
+		printk(BIOS_SPEW,
+		    "PP: 0x%p => cmd = { 0x%02x 0x%02x%02x%02x } chunk_len = %zd\n",
+		     buf + actual, cmd[0], cmd[1], cmd[2], cmd[3], chunk_len);
+
+		ret = spi_flash_cmd(flash->spi, CMD_EN25Q128_WREN, NULL, 0);
+		if (ret < 0) {
+			printk(BIOS_WARNING, "SF: Enabling Write failed\n");
+			break;
+		}
+
+		ret = spi_flash_cmd_write(flash->spi, cmd, 4,
+					  buf + actual, chunk_len);
+		if (ret < 0) {
+			printk(BIOS_WARNING, "SF: EON Page Program failed\n");
+			break;
+		}
+
+		ret = spi_flash_cmd_wait_ready(flash, SPI_FLASH_PROG_TIMEOUT);
+		if (ret)
+			break;
+
+		page_addr++;
+		byte_addr = 0;
+	}
+
+	printk(BIOS_INFO, "SF: EON: Successfully programmed %zu bytes @ 0x%x\n",
+	      len, offset);
+
+	spi_release_bus(flash->spi);
+	return ret;
+}
+
+static int eon_erase(struct spi_flash *flash, u32 offset, size_t len)
+{
+	return spi_flash_cmd_erase(flash, CMD_EN25Q128_BE, offset, len);
+}
+
+struct spi_flash *spi_flash_probe_eon(struct spi_slave *spi, u8 *idcode)
+{
+	const struct eon_spi_flash_params *params;
+	struct eon_spi_flash *eon;
+	unsigned int i;
+
+	for (i = 0; i < ARRAY_SIZE(eon_spi_flash_table); ++i) {
+		params = &eon_spi_flash_table[i];
+		if (params->idcode1 == idcode[2])
+			break;
+	}
+
+	if (i == ARRAY_SIZE(eon_spi_flash_table)) {
+		printk(BIOS_WARNING, "SF: Unsupported EON ID %02x\n", idcode[1]);
+		return NULL;
+	}
+
+	eon = malloc(sizeof(*eon));
+	if (!eon) {
+		printk(BIOS_WARNING, "SF: Failed to allocate memory\n");
+		return NULL;
+	}
+
+	eon->params = params;
+	eon->flash.spi = spi;
+	eon->flash.name = params->name;
+
+	eon->flash.write = eon_write;
+	eon->flash.erase = eon_erase;
+	eon->flash.read = spi_flash_cmd_read_fast;
+	eon->flash.sector_size = params->page_size * params->pages_per_sector
+	    * params->sectors_per_block;
+	eon->flash.size = params->page_size * params->pages_per_sector
+	    * params->nr_sectors;
+
+	return &eon->flash;
+}