SPEAr : smi driver support for SPEAr SoCs

SPEAr SoCs contain a serial memory interface controller. This
controller is used to interface with spi based memories.
This patch adds the driver for this IP.

Signed-off-by: Vipin <vipin.kumar@st.com>

1 files changed, 523 insertions, 0 deletions

diff --git a/drivers/mtd/spr_smi.c b/drivers/mtd/spr_smi.c
new file mode 100755
index 0000000..9a70a19
--- /dev/null
+++ b/drivers/mtd/spr_smi.c
@@ -0,0 +1,523 @@
+/*
+ * (C) Copyright 2009
+ * Vipin Kumar, ST Micoelectronics, vipin.kumar@st.com.
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#include <common.h>
+#include <flash.h>
+#include <linux/err.h>
+
+#include <asm/io.h>
+#include <asm/arch/hardware.h>
+#include <asm/arch/spr_smi.h>
+
+#if !defined(CONFIG_SYS_NO_FLASH)
+
+static struct smi_regs *const smicntl =
+    (struct smi_regs * const)CONFIG_SYS_SMI_BASE;
+static ulong bank_base[CONFIG_SYS_MAX_FLASH_BANKS] =
+    CONFIG_SYS_FLASH_ADDR_BASE;
+flash_info_t flash_info[CONFIG_SYS_MAX_FLASH_BANKS];
+
+#define ST_M25Pxx_ID		0x00002020
+
+static struct flash_dev flash_ids[] = {
+	{0x10, 0x10000, 2},	/* 64K Byte */
+	{0x11, 0x20000, 4},	/* 128K Byte */
+	{0x12, 0x40000, 4},	/* 256K Byte */
+	{0x13, 0x80000, 8},	/* 512K Byte */
+	{0x14, 0x100000, 16},	/* 1M Byte */
+	{0x15, 0x200000, 32},	/* 2M Byte */
+	{0x16, 0x400000, 64},	/* 4M Byte */
+	{0x17, 0x800000, 128},	/* 8M Byte */
+	{0x18, 0x1000000, 64},	/* 16M Byte */
+	{0x00,}
+};
+
+/*
+ * smi_wait_xfer_finish - Wait until TFF is set in status register
+ * @timeout:	 timeout in milliseconds
+ *
+ * Wait until TFF is set in status register
+ */
+static void smi_wait_xfer_finish(int timeout)
+{
+	while (timeout--) {
+		if (readl(&smicntl->smi_sr) & TFF)
+			break;
+		udelay(1000);
+	}
+}
+
+/*
+ * smi_read_id - Read flash id
+ * @info:	 flash_info structure pointer
+ * @banknum:	 bank number
+ *
+ * Read the flash id present at bank #banknum
+ */
+static unsigned int smi_read_id(flash_info_t *info, int banknum)
+{
+	unsigned int value;
+
+	writel(readl(&smicntl->smi_cr1) | SW_MODE, &smicntl->smi_cr1);
+	writel(READ_ID, &smicntl->smi_tr);
+	writel((banknum << BANKSEL_SHIFT) | SEND | TX_LEN_1 | RX_LEN_3,
+	       &smicntl->smi_cr2);
+	smi_wait_xfer_finish(XFER_FINISH_TOUT);
+
+	value = (readl(&smicntl->smi_rr) & 0x00FFFFFF);
+
+	writel(readl(&smicntl->smi_sr) & ~TFF, &smicntl->smi_sr);
+	writel(readl(&smicntl->smi_cr1) & ~SW_MODE, &smicntl->smi_cr1);
+
+	return value;
+}
+
+/*
+ * flash_get_size - Detect the SMI flash by reading the ID.
+ * @base:	 Base address of the flash area bank #banknum
+ * @banknum:	 Bank number
+ *
+ * Detect the SMI flash by reading the ID. Initializes the flash_info structure
+ * with size, sector count etc.
+ */
+static ulong flash_get_size(ulong base, int banknum)
+{
+	flash_info_t *info = &flash_info[banknum];
+	struct flash_dev *dev;
+	unsigned int value;
+	unsigned int density;
+	int i;
+
+	value = smi_read_id(info, banknum);
+	density = (value >> 16) & 0xff;
+
+	for (i = 0, dev = &flash_ids[0]; dev->density != 0x0;
+	     i++, dev = &flash_ids[i]) {
+		if (dev->density == density) {
+			info->size = dev->size;
+			info->sector_count = dev->sector_count;
+			break;
+		}
+	}
+
+	if (dev->density == 0x0)
+		return 0;
+
+	info->flash_id = value & 0xffff;
+	info->start[0] = base;
+
+	return info->size;
+}
+
+/*
+ * smi_read_sr - Read status register of SMI
+ * @bank:	 bank number
+ *
+ * This routine will get the status register of the flash chip present at the
+ * given bank
+ */
+static unsigned int smi_read_sr(int bank)
+{
+	u32 ctrlreg1;
+
+	/* store the CTRL REG1 state */
+	ctrlreg1 = readl(&smicntl->smi_cr1);
+
+	/* Program SMI in HW Mode */
+	writel(readl(&smicntl->smi_cr1) & ~(SW_MODE | WB_MODE),
+	       &smicntl->smi_cr1);
+
+	/* Performing a RSR instruction in HW mode */
+	writel((bank << BANKSEL_SHIFT) | RD_STATUS_REG, &smicntl->smi_cr2);
+
+	smi_wait_xfer_finish(XFER_FINISH_TOUT);
+
+	/* Restore the CTRL REG1 state */
+	writel(ctrlreg1, &smicntl->smi_cr1);
+
+	return readl(&smicntl->smi_sr);
+}
+
+/*
+ * smi_wait_till_ready - Wait till last operation is over.
+ * @bank:	 bank number shifted.
+ * @timeout:	 timeout in milliseconds.
+ *
+ * This routine checks for WIP(write in progress)bit in Status register(SMSR-b0)
+ * The routine checks for #timeout loops, each at interval of 1 milli-second.
+ * If successful the routine returns 0.
+ */
+static int smi_wait_till_ready(int bank, int timeout)
+{
+	int count;
+	unsigned int sr;
+
+	/* One chip guarantees max 5 msec wait here after page writes,
+	   but potentially three seconds (!) after page erase. */
+	for (count = 0; count < timeout; count++) {
+
+		sr = smi_read_sr(bank);
+		if (sr < 0)
+			break;
+		else if (!(sr & WIP_BIT))
+			return 0;
+
+		/* Try again after 1m-sec */
+		udelay(1000);
+	}
+	printf("SMI controller is still in wait, timeout=%d\n", timeout);
+	return -EIO;
+}
+
+/*
+ * smi_write_enable - Enable the flash to do write operation
+ * @bank:	 bank number
+ *
+ * Set write enable latch with Write Enable command.
+ * Returns negative if error occurred.
+ */
+static int smi_write_enable(int bank)
+{
+	u32 ctrlreg1;
+	int timeout = WMODE_TOUT;
+
+	/* Store the CTRL REG1 state */
+	ctrlreg1 = readl(&smicntl->smi_cr1);
+
+	/* Program SMI in H/W Mode */
+	writel(readl(&smicntl->smi_cr1) & ~SW_MODE, &smicntl->smi_cr1);
+
+	/* Give the Flash, Write Enable command */
+	writel((bank << BANKSEL_SHIFT) | WE, &smicntl->smi_cr2);
+
+	smi_wait_xfer_finish(XFER_FINISH_TOUT);
+
+	/* Restore the CTRL REG1 state */
+	writel(ctrlreg1, &smicntl->smi_cr1);
+
+	while (timeout--) {
+		if (smi_read_sr(bank) & (1 << (bank + WM_SHIFT)))
+			break;
+		udelay(1000);
+	}
+
+	if (timeout)
+		return 0;
+
+	return -1;
+}
+
+/*
+ * smi_init - SMI initialization routine
+ *
+ * SMI initialization routine. Sets SMI control register1.
+ */
+static void smi_init(void)
+{
+	/* Setting the fast mode values. SMI working at 166/4 = 41.5 MHz */
+	writel(HOLD1 | FAST_MODE | BANK_EN | DSEL_TIME | PRESCAL4,
+	       &smicntl->smi_cr1);
+}
+
+/*
+ * smi_sector_erase - Erase flash sector
+ * @info:	 flash_info structure pointer
+ * @sector:	 sector number
+ *
+ * Set write enable latch with Write Enable command.
+ * Returns negative if error occurred.
+ */
+static int smi_sector_erase(flash_info_t *info, unsigned int sector)
+{
+	int bank;
+	unsigned int sect_add;
+	unsigned int instruction;
+
+	switch (info->start[0]) {
+	case SMIBANK0_BASE:
+		bank = BANK0;
+		break;
+	case SMIBANK1_BASE:
+		bank = BANK1;
+		break;
+	case SMIBANK2_BASE:
+		bank = BANK2;
+		break;
+	case SMIBANK3_BASE:
+		bank = BANK3;
+		break;
+	default:
+		return -1;
+	}
+
+	sect_add = sector * (info->size / info->sector_count);
+	instruction = ((sect_add >> 8) & 0x0000FF00) | SECTOR_ERASE;
+
+	writel(readl(&smicntl->smi_sr) & ~(ERF1 | ERF2), &smicntl->smi_sr);
+
+	if (info->flash_id == ST_M25Pxx_ID) {
+		/* Wait until finished previous write command. */
+		if (smi_wait_till_ready(bank, CONFIG_SYS_FLASH_ERASE_TOUT))
+			return -EBUSY;
+
+		/* Send write enable, before erase commands. */
+		if (smi_write_enable(bank))
+			return -EIO;
+
+		/* Put SMI in SW mode */
+		writel(readl(&smicntl->smi_cr1) | SW_MODE, &smicntl->smi_cr1);
+
+		/* Send Sector Erase command in SW Mode */
+		writel(instruction, &smicntl->smi_tr);
+		writel((bank << BANKSEL_SHIFT) | SEND | TX_LEN_4,
+		       &smicntl->smi_cr2);
+		smi_wait_xfer_finish(XFER_FINISH_TOUT);
+
+		if (smi_wait_till_ready(bank, CONFIG_SYS_FLASH_ERASE_TOUT))
+			return -EBUSY;
+
+		/* Put SMI in HW mode */
+		writel(readl(&smicntl->smi_cr1) & ~SW_MODE,
+		       &smicntl->smi_cr1);
+
+		return 0;
+	} else {
+		/* Put SMI in HW mode */
+		writel(readl(&smicntl->smi_cr1) & ~SW_MODE,
+		       &smicntl->smi_cr1);
+		return -EINVAL;
+	}
+}
+
+/*
+ * smi_write - Write to SMI flash
+ * @src_addr:	 source buffer
+ * @dst_addr:	 destination buffer
+ * @length:	 length to write in words
+ * @bank:	 bank base address
+ *
+ * Write to SMI flash
+ */
+static int smi_write(unsigned int *src_addr, unsigned int *dst_addr,
+		     unsigned int length, ulong bank_addr)
+{
+	int banknum;
+	unsigned int WM;
+
+	switch (bank_addr) {
+	case SMIBANK0_BASE:
+		banknum = BANK0;
+		WM = WM0;
+		break;
+	case SMIBANK1_BASE:
+		banknum = BANK1;
+		WM = WM1;
+		break;
+	case SMIBANK2_BASE:
+		banknum = BANK2;
+		WM = WM2;
+		break;
+	case SMIBANK3_BASE:
+		banknum = BANK3;
+		WM = WM3;
+		break;
+	default:
+		return -1;
+	}
+
+	if (smi_wait_till_ready(banknum, CONFIG_SYS_FLASH_WRITE_TOUT))
+		return -EBUSY;
+
+	/* Set SMI in Hardware Mode */
+	writel(readl(&smicntl->smi_cr1) & ~SW_MODE, &smicntl->smi_cr1);
+
+	if (smi_write_enable(banknum))
+		return -EIO;
+
+	/* Perform the write command */
+	while (length--) {
+		if (((ulong) (dst_addr) % SFLASH_PAGE_SIZE) == 0) {
+			if (smi_wait_till_ready(banknum,
+						CONFIG_SYS_FLASH_WRITE_TOUT))
+				return -EBUSY;
+
+			if (smi_write_enable(banknum))
+				return -EIO;
+		}
+
+		*dst_addr++ = *src_addr++;
+
+		if ((readl(&smicntl->smi_sr) & (ERF1 | ERF2)))
+			return -EIO;
+	}
+
+	if (smi_wait_till_ready(banknum, CONFIG_SYS_FLASH_WRITE_TOUT))
+		return -EBUSY;
+
+	writel(readl(&smicntl->smi_sr) & ~(WCF), &smicntl->smi_sr);
+
+	return 0;
+}
+
+/*
+ * write_buff - Write to SMI flash
+ * @info:	 flash info structure
+ * @src:	 source buffer
+ * @dest_addr:	 destination buffer
+ * @length:	 length to write in words
+ *
+ * Write to SMI flash
+ */
+int write_buff(flash_info_t *info, uchar *src, ulong dest_addr, ulong length)
+{
+	return smi_write((unsigned int *)src, (unsigned int *)dest_addr,
+		  (length + 3) / 4, info->start[0]);
+}
+
+/*
+ * flash_init - SMI flash initialization
+ *
+ * SMI flash initialization
+ */
+unsigned long flash_init(void)
+{
+	unsigned long size = 0;
+	int i, j;
+
+	smi_init();
+
+	for (i = 0; i < CONFIG_SYS_MAX_FLASH_BANKS; i++) {
+		flash_info[i].flash_id = FLASH_UNKNOWN;
+		size += flash_info[i].size = flash_get_size(bank_base[i], i);
+	}
+
+	for (j = 0; j < CONFIG_SYS_MAX_FLASH_BANKS; j++) {
+		for (i = 1; i < flash_info[j].sector_count; i++)
+			flash_info[j].start[i] =
+			    flash_info[j].start[i - 1] +
+			    flash_info->size / flash_info->sector_count;
+
+	}
+
+	return size;
+}
+
+/*
+ * flash_print_info - Print SMI flash information
+ *
+ * Print SMI flash information
+ */
+void flash_print_info(flash_info_t *info)
+{
+	int i;
+	if (info->flash_id == FLASH_UNKNOWN) {
+		puts("missing or unknown FLASH type\n");
+		return;
+	}
+	printf("  Size: %ld MB in %d Sectors\n",
+	       info->size >> 20, info->sector_count);
+
+	puts("  Sector Start Addresses:");
+	for (i = 0; i < info->sector_count; ++i) {
+#ifdef CONFIG_SYS_FLASH_EMPTY_INFO
+		int size;
+		int erased;
+		u32 *flash;
+
+		/*
+		 * Check if whole sector is erased
+		 */
+		size = (info->size) / (info->sector_count);
+		flash = (u32 *) info->start[i];
+		size = size / sizeof(int);
+
+		while ((size--) && (*flash++ == ~0))
+			;
+
+		size++;
+		if (size)
+			erased = 0;
+		else
+			erased = 1;
+
+		if ((i % 5) == 0)
+			printf("\n");
+
+		printf(" %08lX%s%s",
+		       info->start[i],
+		       erased ? " E" : "  ", info->protect[i] ? "RO " : "   ");
+#else
+		if ((i % 5) == 0)
+			printf("\n   ");
+		printf(" %08lX%s",
+		       info->start[i], info->protect[i] ? " (RO)  " : "     ");
+#endif
+	}
+	putc('\n');
+	return;
+}
+
+/*
+ * flash_erase - Erase SMI flash
+ *
+ * Erase SMI flash
+ */
+int flash_erase(flash_info_t *info, int s_first, int s_last)
+{
+	int rcode = 0;
+	int prot = 0;
+	flash_sect_t sect;
+
+	if (info->flash_id != ST_M25Pxx_ID) {
+		puts("Can't erase unknown flash type - aborted\n");
+		return 1;
+	}
+
+	if ((s_first < 0) || (s_first > s_last)) {
+		puts("- no sectors to erase\n");
+		return 1;
+	}
+
+	for (sect = s_first; sect <= s_last; ++sect) {
+		if (info->protect[sect])
+			prot++;
+	}
+	if (prot) {
+		printf("- Warning: %d protected sectors will not be erased!\n",
+		       prot);
+	} else {
+		putc('\n');
+	}
+
+	for (sect = s_first; sect <= s_last; sect++) {
+		if (info->protect[sect] == 0) {
+			if (smi_sector_erase(info, sect))
+				rcode = 1;
+			else
+				putc('.');
+		}
+	}
+	puts(" done\n");
+	return rcode;
+}
+#endif