src/drivers/spi: introduce AMIC support

Add support for the AMIC A25L032 flash chip.

Change-Id: Ie8d441a923c6fbd18c16440b4571321652d934d5
Signed-off-by: Idwer Vollering <vidwer@gmail.com>
Reviewed-on: http://review.coreboot.org/5252
Tested-by: build bot (Jenkins)
Reviewed-by: Kyösti Mälkki <kyosti.malkki@gmail.com>

src/drivers/spi/Kconfig

@@ -31,6 +31,14 @@ config SPI_FLASH_SMM
 	help
 	  Select this option if you want SPI flash support in SMM.
 
+config SPI_FLASH_AMIC
+	bool
+	default y
+	depends on SPI_FLASH
+	help
+	  Select this option if your chipset driver needs to store certain
+	  data in the SPI flash and your SPI flash is made by AMIC.
+
 config SPI_FLASH_EON
 	bool
 	default y

src/drivers/spi/Makefile.inc

@@ -2,6 +2,7 @@
 ramstage-$(CONFIG_SPI_FLASH) += spi_flash.c
 
 # drivers
+ramstage-$(CONFIG_SPI_FLASH_AMIC) += amic.c
 ramstage-$(CONFIG_SPI_FLASH_EON) += eon.c
 ramstage-$(CONFIG_SPI_FLASH_MACRONIX) += macronix.c
 ramstage-$(CONFIG_SPI_FLASH_SPANSION) += spansion.c
@@ -16,6 +17,7 @@ ifeq ($(CONFIG_SPI_FLASH_SMM),y)
 smm-$(CONFIG_SPI_FLASH) += spi_flash.c
 
 # drivers
+smm-$(CONFIG_SPI_FLASH_AMIC) += amic.c
 smm-$(CONFIG_SPI_FLASH_EON) += eon.c
 smm-$(CONFIG_SPI_FLASH_MACRONIX) += macronix.c
 smm-$(CONFIG_SPI_FLASH_SPANSION) += spansion.c

src/drivers/spi/amic.c

@@ -0,0 +1,179 @@
+/*
+ * Copyright (C) 2014 Idwer Vollering <vidwer@gmail.com>
+ *
+ * Based on winbond.c
+ *
+ * Copyright 2008, Network Appliance Inc.
+ * Author: Jason McMullan <mcmullan <at> netapp.com>
+ * Licensed under the GPL-2 or later.
+ */
+
+#include <stdlib.h>
+#include <spi_flash.h>
+#include "spi_flash_internal.h"
+
+/* A25L-specific commands */
+#define CMD_A25_WREN		0x06	/* Write Enable */
+#define CMD_A25_WRDI		0x04	/* Write Disable */
+#define CMD_A25_RDSR		0x05	/* Read Status Register */
+#define CMD_A25_WRSR		0x01	/* Write Status Register */
+#define CMD_A25_READ		0x03	/* Read Data Bytes */
+#define CMD_A25_FAST_READ	0x0b	/* Read Data Bytes at Higher Speed */
+#define CMD_A25_PP		0x02	/* Page Program */
+#define CMD_A25_SE		0x20	/* Sector (4K) Erase */
+#define CMD_A25_BE		0xd8	/* Block (64K) Erase */
+#define CMD_A25_CE		0xc7	/* Chip Erase */
+#define CMD_A25_DP		0xb9	/* Deep Power-down */
+#define CMD_A25_RES		0xab	/* Release from DP, and Read Signature */
+
+struct amic_spi_flash_params {
+	uint16_t	id;
+	/* Log2 of page size in power-of-two mode */
+	uint8_t		l2_page_size;
+	uint16_t	pages_per_sector;
+	uint16_t	sectors_per_block;
+	uint16_t	nr_blocks;
+	const char	*name;
+};
+
+/* spi_flash needs to be first so upper layers can free() it */
+struct amic_spi_flash {
+	struct spi_flash flash;
+	const struct amic_spi_flash_params *params;
+};
+
+static inline struct amic_spi_flash *
+to_amic_spi_flash(struct spi_flash *flash)
+{
+	return container_of(flash, struct amic_spi_flash, flash);
+}
+
+static const struct amic_spi_flash_params amic_spi_flash_table[] = {
+	{
+		.id			= 0x3016,
+		.l2_page_size		= 8,
+		.pages_per_sector	= 16,
+		.sectors_per_block	= 16,
+		.nr_blocks		= 64,
+		.name			= "A25L032",
+	},
+};
+
+static int amic_write(struct spi_flash *flash,
+		u32 offset, size_t len, const void *buf)
+{
+	struct amic_spi_flash *amic = to_amic_spi_flash(flash);
+	unsigned long byte_addr;
+	unsigned long page_size;
+	size_t chunk_len;
+	size_t actual;
+	int ret;
+	u8 cmd[4];
+
+	page_size = min(1 << amic->params->l2_page_size, CONTROLLER_PAGE_LIMIT);
+	byte_addr = offset % page_size;
+
+	flash->spi->rw = SPI_WRITE_FLAG;
+	ret = spi_claim_bus(flash->spi);
+	if (ret) {
+		printk(BIOS_WARNING, "SF: Unable to claim SPI bus\n");
+		return ret;
+	}
+
+	for (actual = 0; actual < len; actual += chunk_len) {
+		chunk_len = min(len - actual, page_size - byte_addr);
+
+		cmd[0] = CMD_A25_PP;
+		cmd[1] = (offset >> 16) & 0xff;
+		cmd[2] = (offset >> 8) & 0xff;
+		cmd[3] = offset & 0xff;
+#if CONFIG_DEBUG_SPI_FLASH
+		printk(BIOS_SPEW, "PP: 0x%p => cmd = { 0x%02x 0x%02x%02x%02x }"
+		        " chunk_len = %zu\n", buf + actual,
+			cmd[0], cmd[1], cmd[2], cmd[3], chunk_len);
+#endif
+
+		ret = spi_flash_cmd(flash->spi, CMD_A25_WREN, NULL, 0);
+		if (ret < 0) {
+			printk(BIOS_WARNING, "SF: Enabling Write failed\n");
+			goto out;
+		}
+
+		ret = spi_flash_cmd_write(flash->spi, cmd, 4,
+				buf + actual, chunk_len);
+		if (ret < 0) {
+			printk(BIOS_WARNING, "SF: AMIC Page Program failed\n");
+			goto out;
+		}
+
+		ret = spi_flash_cmd_wait_ready(flash, SPI_FLASH_PROG_TIMEOUT);
+		if (ret)
+			goto out;
+
+		offset += chunk_len;
+		byte_addr = 0;
+	}
+
+#if CONFIG_DEBUG_SPI_FLASH
+	printk(BIOS_SPEW, "SF: AMIC: Successfully programmed %zu bytes @"
+			" 0x%lx\n", len, (unsigned long)(offset - len));
+#endif
+	ret = 0;
+
+out:
+	spi_release_bus(flash->spi);
+	return ret;
+}
+
+static int amic_erase(struct spi_flash *flash, u32 offset, size_t len)
+{
+	return spi_flash_cmd_erase(flash, CMD_A25_SE, offset, len);
+}
+
+struct spi_flash *spi_flash_probe_amic(struct spi_slave *spi, u8 *idcode)
+{
+	const struct amic_spi_flash_params *params;
+	unsigned page_size;
+	struct amic_spi_flash *amic;
+	unsigned int i;
+
+	for (i = 0; i < ARRAY_SIZE(amic_spi_flash_table); i++) {
+		params = &amic_spi_flash_table[i];
+		if (params->id == ((idcode[1] << 8) | idcode[2]))
+			break;
+	}
+
+	if (i == ARRAY_SIZE(amic_spi_flash_table)) {
+		printk(BIOS_WARNING, "SF: Unsupported AMIC ID %02x%02x\n",
+				idcode[1], idcode[2]);
+		return NULL;
+	}
+
+	amic = malloc(sizeof(struct amic_spi_flash));
+	if (!amic) {
+		printk(BIOS_WARNING, "SF: Failed to allocate memory\n");
+		return NULL;
+	}
+
+	amic->params = params;
+	amic->flash.spi = spi;
+	amic->flash.name = params->name;
+
+	/* Assuming power-of-two page size initially. */
+	page_size = 1 << params->l2_page_size;
+
+	amic->flash.write = amic_write;
+	amic->flash.erase = amic_erase;
+#if CONFIG_SPI_FLASH_NO_FAST_READ
+	amic->flash.read = spi_flash_cmd_read_slow;
+#else
+	amic->flash.read = spi_flash_cmd_read_fast;
+#endif
+	amic->flash.sector_size = (1 << amic->params->l2_page_size) *
+		amic->params->pages_per_sector;
+	amic->flash.size = page_size * params->pages_per_sector
+				* params->sectors_per_block
+				* params->nr_blocks;
+
+	return &amic->flash;
+}

src/drivers/spi/spi_flash.c

@@ -218,6 +218,9 @@ static struct {
 	struct spi_flash *(*probe) (struct spi_slave *spi, u8 *idcode);
 } flashes[] = {
 	/* Keep it sorted by define name */
+#if CONFIG_SPI_FLASH_AMIC
+	{ 0, 0x37, spi_flash_probe_amic, },
+#endif
 #if CONFIG_SPI_FLASH_EON
 	{ 0, 0x1c, spi_flash_probe_eon, },
 #endif

src/drivers/spi/spi_flash_internal.h

@@ -72,6 +72,7 @@ int spi_flash_cmd_erase(struct spi_flash *flash, u8 erase_cmd,
 
 /* Manufacturer-specific probe functions */
 struct spi_flash *spi_flash_probe_spansion(struct spi_slave *spi, u8 *idcode);
+struct spi_flash *spi_flash_probe_amic(struct spi_slave *spi, u8 *idcode);
 struct spi_flash *spi_flash_probe_atmel(struct spi_slave *spi, u8 *idcode);
 struct spi_flash *spi_flash_probe_eon(struct spi_slave *spi, u8 *idcode);
 struct spi_flash *spi_flash_probe_macronix(struct spi_slave *spi, u8 *idcode);