Atmel MCI driver

Driver for the Atmel MCI controller (MMC interface) for AT32AP CPUs.

The AT91 ARM-based CPUs use basically the same hardware, so it should
be possible to share this driver, but no effort has been made so far.

Hardware documentation can be found in the AT32AP7000 data sheet,
which can be downloaded from

http://www.atmel.com/dyn/products/datasheets.asp?family_id=682

Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>

1 files changed, 477 insertions, 0 deletions

diff --git a/cpu/at32ap/atmel_mci.c b/cpu/at32ap/atmel_mci.c
new file mode 100644
index 0000000..3e3789b
--- /dev/null
+++ b/cpu/at32ap/atmel_mci.c
@@ -0,0 +1,477 @@
+/*
+ * Copyright (C) 2004-2006 Atmel Corporation
+ *
+ * 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>
+
+#ifdef CONFIG_MMC
+
+#include <part.h>
+#include <mmc.h>
+
+#include <asm/io.h>
+#include <asm/errno.h>
+#include <asm/byteorder.h>
+#include <asm/arch/clk.h>
+#include <asm/arch/memory-map.h>
+
+#include "atmel_mci.h"
+
+#ifdef DEBUG
+#define pr_debug(fmt, args...) printf(fmt, ##args)
+#else
+#define pr_debug(...) do { } while(0)
+#endif
+
+#ifndef CFG_MMC_CLK_OD
+#define CFG_MMC_CLK_OD		150000
+#endif
+
+#ifndef CFG_MMC_CLK_PP
+#define CFG_MMC_CLK_PP		5000000
+#endif
+
+#ifndef CFG_MMC_OP_COND
+#define CFG_MMC_OP_COND		0x00100000
+#endif
+
+#define MMC_DEFAULT_BLKLEN	512
+#define MMC_DEFAULT_RCA		1
+
+static unsigned int mmc_rca;
+static block_dev_desc_t mmc_blkdev;
+
+block_dev_desc_t *mmc_get_dev(int dev)
+{
+	return &mmc_blkdev;
+}
+
+static void mci_set_mode(unsigned long hz, unsigned long blklen)
+{
+	unsigned long bus_hz;
+	unsigned long clkdiv;
+
+	bus_hz = get_mci_clk_rate();
+	clkdiv = (bus_hz / hz) / 2 - 1;
+
+	pr_debug("mmc: setting clock %lu Hz, block size %lu\n",
+		 hz, blklen);
+
+	if (clkdiv & ~255UL) {
+		clkdiv = 255;
+		printf("mmc: clock %lu too low; setting CLKDIV to 255\n",
+			hz);
+	}
+
+	blklen &= 0xfffc;
+	mmci_writel(MR, (MMCI_BF(CLKDIV, clkdiv)
+			 | MMCI_BF(BLKLEN, blklen)));
+}
+
+#define RESP_NO_CRC	1
+#define R1		MMCI_BF(RSPTYP, 1)
+#define R2		MMCI_BF(RSPTYP, 2)
+#define R3		(R1 | RESP_NO_CRC)
+#define R6		R1
+#define NID		MMCI_BF(MAXLAT, 0)
+#define NCR		MMCI_BF(MAXLAT, 1)
+#define TRCMD_START	MMCI_BF(TRCMD, 1)
+#define TRDIR_READ	MMCI_BF(TRDIR, 1)
+#define TRTYP_BLOCK	MMCI_BF(TRTYP, 0)
+#define INIT_CMD	MMCI_BF(SPCMD, 1)
+#define OPEN_DRAIN	MMCI_BF(OPDCMD, 1)
+
+#define ERROR_FLAGS	(MMCI_BIT(DTOE)			\
+			 | MMCI_BIT(RDIRE)		\
+			 | MMCI_BIT(RENDE)		\
+			 | MMCI_BIT(RINDE)		\
+			 | MMCI_BIT(RTOE))
+
+static int
+mmc_cmd(unsigned long cmd, unsigned long arg,
+	void *resp, unsigned long flags)
+{
+	unsigned long *response = resp;
+	int i, response_words = 0;
+	unsigned long error_flags;
+	u32 status;
+
+	pr_debug("mmc: CMD%lu 0x%lx (flags 0x%lx)\n",
+		 cmd, arg, flags);
+
+	error_flags = ERROR_FLAGS;
+	if (!(flags & RESP_NO_CRC))
+		error_flags |= MMCI_BIT(RCRCE);
+
+	flags &= ~MMCI_BF(CMDNB, ~0UL);
+
+	if (MMCI_BFEXT(RSPTYP, flags) == MMCI_RSPTYP_48_BIT_RESP)
+		response_words = 1;
+	else if (MMCI_BFEXT(RSPTYP, flags) == MMCI_RSPTYP_136_BIT_RESP)
+		response_words = 4;
+
+	mmci_writel(ARGR, arg);
+	mmci_writel(CMDR, cmd | flags);
+	do {
+		udelay(40);
+		status = mmci_readl(SR);
+	} while (!(status & MMCI_BIT(CMDRDY)));
+
+	pr_debug("mmc: status 0x%08lx\n", status);
+
+	if (status & ERROR_FLAGS) {
+		printf("mmc: command %lu failed (status: 0x%08lx)\n",
+		       cmd, status);
+		return -EIO;
+	}
+
+	if (response_words)
+		pr_debug("mmc: response:");
+
+	for (i = 0; i < response_words; i++) {
+		response[i] = mmci_readl(RSPR);
+		pr_debug(" %08lx", response[i]);
+	}
+	pr_debug("\n");
+
+	return 0;
+}
+
+static int mmc_acmd(unsigned long cmd, unsigned long arg,
+		    void *resp, unsigned long flags)
+{
+	unsigned long aresp[4];
+	int ret;
+
+	/*
+	 * Seems like the APP_CMD part of an ACMD has 64 cycles max
+	 * latency even though the ACMD part doesn't. This isn't
+	 * entirely clear in the SD Card spec, but some cards refuse
+	 * to work if we attempt to use 5 cycles max latency here...
+	 */
+	ret = mmc_cmd(MMC_CMD_APP_CMD, 0, aresp,
+		      R1 | NCR | (flags & OPEN_DRAIN));
+	if (ret)
+		return ret;
+	if ((aresp[0] & (R1_ILLEGAL_COMMAND | R1_APP_CMD)) != R1_APP_CMD)
+		return -ENODEV;
+
+	ret = mmc_cmd(cmd, arg, resp, flags);
+	return ret;
+}
+
+static unsigned long
+mmc_bread(int dev, unsigned long start, lbaint_t blkcnt,
+	  unsigned long *buffer)
+{
+	int ret, i = 0;
+	unsigned long resp[4];
+	unsigned long card_status, data;
+	unsigned long wordcount;
+	u32 status;
+
+	if (blkcnt == 0)
+		return 0;
+
+	pr_debug("mmc_bread: dev %d, start %lx, blkcnt %lx\n",
+		 dev, start, blkcnt);
+
+	/* Put the device into Transfer state */
+	ret = mmc_cmd(MMC_CMD_SELECT_CARD, mmc_rca << 16, resp, R1 | NCR);
+	if (ret) goto fail;
+
+	/* Set block length */
+	ret = mmc_cmd(MMC_CMD_SET_BLOCKLEN, mmc_blkdev.blksz, resp, R1 | NCR);
+	if (ret) goto fail;
+
+	pr_debug("MCI_DTOR = %08lx\n", mmci_readl(DTOR));
+
+	for (i = 0; i < blkcnt; i++, start++) {
+		ret = mmc_cmd(MMC_CMD_READ_SINGLE_BLOCK,
+			      start * mmc_blkdev.blksz, resp,
+			      (R1 | NCR | TRCMD_START | TRDIR_READ
+			       | TRTYP_BLOCK));
+		if (ret) goto fail;
+
+		ret = -EIO;
+		wordcount = 0;
+		do {
+			do {
+				status = mmci_readl(SR);
+				if (status & (ERROR_FLAGS | MMCI_BIT(OVRE)))
+					goto fail;
+			} while (!(status & MMCI_BIT(RXRDY)));
+
+			if (status & MMCI_BIT(RXRDY)) {
+				data = mmci_readl(RDR);
+				// pr_debug("%x\n", data);
+				*buffer++ = data;
+				wordcount++;
+			}
+		} while(wordcount < (512 / 4));
+
+		pr_debug("mmc: read %u words, waiting for BLKE\n", wordcount);
+
+		do {
+			status = mmci_readl(SR);
+		} while (!(status & MMCI_BIT(BLKE)));
+
+		putc('.');
+	}
+
+out:
+	/* Put the device back into Standby state */
+	mmc_cmd(MMC_CMD_SELECT_CARD, 0, resp, NCR);
+	return i;
+
+fail:
+	mmc_cmd(MMC_CMD_SEND_STATUS, mmc_rca << 16, &card_status, R1 | NCR);
+	printf("mmc: bread failed, card status = ", card_status);
+	goto out;
+}
+
+static void mmc_parse_cid(struct mmc_cid *cid, unsigned long *resp)
+{
+	cid->mid = resp[0] >> 24;
+	cid->oid = (resp[0] >> 8) & 0xffff;
+	cid->pnm[0] = resp[0];
+	cid->pnm[1] = resp[1] >> 24;
+	cid->pnm[2] = resp[1] >> 16;
+	cid->pnm[3] = resp[1] >> 8;
+	cid->pnm[4] = resp[1];
+	cid->pnm[5] = resp[2] >> 24;
+	cid->pnm[6] = 0;
+	cid->prv = resp[2] >> 16;
+	cid->psn = (resp[2] << 16) | (resp[3] >> 16);
+	cid->mdt = resp[3] >> 8;
+}
+
+static void sd_parse_cid(struct mmc_cid *cid, unsigned long *resp)
+{
+	cid->mid = resp[0] >> 24;
+	cid->oid = (resp[0] >> 8) & 0xffff;
+	cid->pnm[0] = resp[0];
+	cid->pnm[1] = resp[1] >> 24;
+	cid->pnm[2] = resp[1] >> 16;
+	cid->pnm[3] = resp[1] >> 8;
+	cid->pnm[4] = resp[1];
+	cid->pnm[5] = 0;
+	cid->pnm[6] = 0;
+	cid->prv = resp[2] >> 24;
+	cid->psn = (resp[2] << 8) | (resp[3] >> 24);
+	cid->mdt = (resp[3] >> 8) & 0x0fff;
+}
+
+static void mmc_dump_cid(const struct mmc_cid *cid)
+{
+	printf("Manufacturer ID:       %02lX\n", cid->mid);
+	printf("OEM/Application ID:    %04lX\n", cid->oid);
+	printf("Product name:          %s\n", cid->pnm);
+	printf("Product Revision:      %lu.%lu\n",
+	       cid->prv >> 4, cid->prv & 0x0f);
+	printf("Product Serial Number: %lu\n", cid->psn);
+	printf("Manufacturing Date:    %02lu/%02lu\n",
+	       cid->mdt >> 4, cid->mdt & 0x0f);
+}
+
+static void mmc_dump_csd(const struct mmc_csd *csd)
+{
+	unsigned long *csd_raw = (unsigned long *)csd;
+	printf("CSD data: %08lx %08lx %08lx %08lx\n",
+	       csd_raw[0], csd_raw[1], csd_raw[2], csd_raw[3]);
+	printf("CSD structure version:   1.%u\n", csd->csd_structure);
+	printf("MMC System Spec version: %u\n", csd->spec_vers);
+	printf("Card command classes:    %03x\n", csd->ccc);
+	printf("Read block length:       %u\n", 1 << csd->read_bl_len);
+	if (csd->read_bl_partial)
+		puts("Supports partial reads\n");
+	else
+		puts("Does not support partial reads\n");
+	printf("Write block length:      %u\n", 1 << csd->write_bl_len);
+	if (csd->write_bl_partial)
+		puts("Supports partial writes\n");
+	else
+		puts("Does not support partial writes\n");
+	if (csd->wp_grp_enable)
+		printf("Supports group WP:      %u\n", csd->wp_grp_size + 1);
+	else
+		puts("Does not support group WP\n");
+	printf("Card capacity:		%u bytes\n",
+	       (csd->c_size + 1) * (1 << (csd->c_size_mult + 2)) *
+	       (1 << csd->read_bl_len));
+	printf("File format:            %u/%u\n",
+	       csd->file_format_grp, csd->file_format);
+	puts("Write protection:        ");
+	if (csd->perm_write_protect)
+		puts(" permanent");
+	if (csd->tmp_write_protect)
+		puts(" temporary");
+	putc('\n');
+}
+
+static int mmc_idle_cards(void)
+{
+	int ret;
+
+	/* Reset and initialize all cards */
+	ret = mmc_cmd(MMC_CMD_GO_IDLE_STATE, 0, NULL, 0);
+	if (ret)
+		return ret;
+
+	/* Keep the bus idle for 74 clock cycles */
+	return mmc_cmd(0, 0, NULL, INIT_CMD);
+}
+
+static int sd_init_card(struct mmc_cid *cid, int verbose)
+{
+	unsigned long resp[4];
+	int i, ret = 0;
+
+	mmc_idle_cards();
+	for (i = 0; i < 1000; i++) {
+		ret = mmc_acmd(MMC_ACMD_SD_SEND_OP_COND, CFG_MMC_OP_COND,
+			       resp, R3 | NID);
+		if (ret || (resp[0] & 0x80000000))
+			break;
+		ret = -ETIMEDOUT;
+	}
+
+	if (ret)
+		return ret;
+
+	ret = mmc_cmd(MMC_CMD_ALL_SEND_CID, 0, resp, R2 | NID);
+	if (ret)
+		return ret;
+	sd_parse_cid(cid, resp);
+	if (verbose)
+		mmc_dump_cid(cid);
+
+	/* Get RCA of the card that responded */
+	ret = mmc_cmd(MMC_CMD_SD_SEND_RELATIVE_ADDR, 0, resp, R6 | NCR);
+	if (ret)
+		return ret;
+
+	mmc_rca = resp[0] >> 16;
+	if (verbose)
+		printf("SD Card detected (RCA %u)\n", mmc_rca);
+	return 0;
+}
+
+static int mmc_init_card(struct mmc_cid *cid, int verbose)
+{
+	unsigned long resp[4];
+	int i, ret = 0;
+
+	mmc_idle_cards();
+	for (i = 0; i < 1000; i++) {
+		ret = mmc_cmd(MMC_CMD_SEND_OP_COND, CFG_MMC_OP_COND, resp,
+			      R3 | NID | OPEN_DRAIN);
+		if (ret || (resp[0] & 0x80000000))
+			break;
+		ret = -ETIMEDOUT;
+	}
+
+	if (ret)
+		return ret;
+
+	/* Get CID of all cards. FIXME: Support more than one card */
+	ret = mmc_cmd(MMC_CMD_ALL_SEND_CID, 0, resp, R2 | NID | OPEN_DRAIN);
+	if (ret)
+		return ret;
+	mmc_parse_cid(cid, resp);
+	if (verbose)
+		mmc_dump_cid(cid);
+
+	/* Set Relative Address of the card that responded */
+	ret = mmc_cmd(MMC_CMD_SET_RELATIVE_ADDR, mmc_rca << 16, resp,
+		      R1 | NCR | OPEN_DRAIN);
+	return ret;
+}
+
+int mmc_init(int verbose)
+{
+	struct mmc_cid cid;
+	struct mmc_csd csd;
+	int ret;
+
+	/* Initialize controller */
+	mmci_writel(CR, MMCI_BIT(SWRST));
+	mmci_writel(CR, MMCI_BIT(MCIEN));
+	mmci_writel(DTOR, 0x5f);
+	mmci_writel(IDR, ~0UL);
+	mci_set_mode(CFG_MMC_CLK_OD, MMC_DEFAULT_BLKLEN);
+
+	ret = sd_init_card(&cid, verbose);
+	if (ret) {
+		mmc_rca = MMC_DEFAULT_RCA;
+		ret = mmc_init_card(&cid, verbose);
+	}
+	if (ret)
+		return ret;
+
+	/* Get CSD from the card */
+	ret = mmc_cmd(MMC_CMD_SEND_CSD, mmc_rca << 16, &csd, R2 | NCR);
+	if (ret)
+		return ret;
+	if (verbose)
+		mmc_dump_csd(&csd);
+
+	/* Initialize the blockdev structure */
+	mmc_blkdev.if_type = IF_TYPE_MMC;
+	mmc_blkdev.part_type = PART_TYPE_DOS;
+	mmc_blkdev.block_read = mmc_bread;
+	sprintf((char *)mmc_blkdev.vendor,
+		"Man %02x%04x Snr %08x",
+		cid.mid, cid.oid, cid.psn);
+	strncpy((char *)mmc_blkdev.product, cid.pnm,
+		sizeof(mmc_blkdev.product));
+	sprintf((char *)mmc_blkdev.revision, "%x %x",
+		cid.prv >> 4, cid.prv & 0x0f);
+	mmc_blkdev.blksz = 1 << csd.read_bl_len;
+	mmc_blkdev.lba = (csd.c_size + 1) * (1 << (csd.c_size_mult + 2));
+
+	mci_set_mode(CFG_MMC_CLK_PP, mmc_blkdev.blksz);
+
+#if 0
+	if (fat_register_device(&mmc_blkdev, 1))
+		printf("Could not register MMC fat device\n");
+#else
+	init_part(&mmc_blkdev);
+#endif
+
+	return 0;
+}
+
+int mmc_read(ulong src, uchar *dst, int size)
+{
+	return -ENOSYS;
+}
+
+int mmc_write(uchar *src, ulong dst, int size)
+{
+	return -ENOSYS;
+}
+
+int mmc2info(ulong addr)
+{
+	return 0;
+}
+
+#endif /* CONFIG_MMC */