Added sd driver for bcm2835 (Raspberry PI)

Replaced defines according to sdhci.h

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

1 files changed, 591 insertions, 0 deletions

diff --git a/drivers/mci/mci-bcm2835.c b/drivers/mci/mci-bcm2835.c
new file mode 100644
index 0000000000..b76f134af2
--- /dev/null
+++ b/drivers/mci/mci-bcm2835.c
@@ -0,0 +1,591 @@
+/*
+ * Raspberry PI MCI driver
+ *
+ * Support for SDHCI device on bcm2835
+ * Based on sdhci-bcm2708.c (c) 2010 Broadcom
+ * Inspired by bcm2835_sdhci.c from git://github.com/gonzoua/u-boot-pi.git
+ *
+ * Portions (e.g. read/write macros, concepts for back-to-back register write
+ * timing workarounds) obviously extracted from the Linux kernel at:
+ * https://github.com/raspberrypi/linux.git rpi-3.6.y
+ *
+ * The Linux kernel code has the following (c) and license, which is hence
+ * propagated to here:
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * 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., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ * Author: Wilhelm Lundgren <wilhelm.lundgren@cybercom.com>
+ */
+
+#include <common.h>
+#include <init.h>
+#include <mci.h>
+#include <io.h>
+#include <malloc.h>
+#include <clock.h>
+#include "mci-bcm2835.h"
+#include "sdhci.h"
+
+#define to_bcm2835_host(h)	container_of(h, struct bcm2835_mci_host, mci)
+static int twoticks_delay;
+struct bcm2835_mci_host {
+	struct mci_host mci;
+	void __iomem *regs;
+	struct device_d *hw_dev;
+	int bus_width;
+	u32 clock;
+	u32 max_clock;
+	u32 version;
+	uint64_t last_write;
+};
+
+void bcm2835_mci_write(struct bcm2835_mci_host *host, u32 reg, u32 val)
+{
+	/*
+	 * The Arasan has a bugette whereby it may lose the content of
+	 * successive writes to registers that are within two SD-card clock
+	 * cycles of each other (a clock domain crossing problem).
+	 * It seems, however, that the data register does not have this problem.
+	 * (Which is just as well - otherwise we'd have to nobble the DMA engine
+	 * too)
+	 */
+
+	if (host->last_write != 0)
+		while ((get_time_ns() - host->last_write) < twoticks_delay)
+			;
+	host->last_write = get_time_ns();
+	writel(val, host->regs + reg);
+}
+
+u32 bcm2835_mci_read(struct bcm2835_mci_host *host, u32 reg)
+{
+	return readl(host->regs + reg);
+}
+
+/* Create special write data function since the data
+ * register is not affected by the twoticks_delay bug
+ * and we can thus get better speed here
+ */
+void bcm2835_mci_write_data(struct bcm2835_mci_host *host, u32 *p)
+{
+	writel(*p, host->regs + SDHCI_BUFFER);
+}
+
+/* Make a read data functions as well just to keep structure */
+void bcm2835_mci_read_data(struct bcm2835_mci_host *host, u32 *p)
+{
+	*p = readl(host->regs + SDHCI_BUFFER);
+}
+
+static int bcm2835_mci_transfer_data(struct bcm2835_mci_host *host,
+		struct mci_cmd *cmd, struct mci_data *data) {
+	u32 *p;
+	u32 data_size, status, intr_status = 0;
+	u32 data_ready_intr_mask;
+	u32 data_ready_status_mask;
+	int i = 0;
+	void (*read_write_func)(struct bcm2835_mci_host*, u32*);
+
+	data_size = data->blocksize * data->blocks;
+
+	if (data->flags & MMC_DATA_READ) {
+		p = (u32 *) data->dest;
+		data_ready_intr_mask = IRQSTAT_BRR;
+		data_ready_status_mask = PRSSTAT_BREN;
+		read_write_func = &bcm2835_mci_read_data;
+	} else {
+		p = (u32 *) data->src;
+		data_ready_intr_mask = IRQSTAT_BWR;
+		data_ready_status_mask = PRSSTAT_BWEN;
+		read_write_func = &bcm2835_mci_write_data;
+	}
+	do {
+		intr_status = bcm2835_mci_read(host, SDHCI_INT_STATUS);
+		if (intr_status & IRQSTAT_CIE) {
+			dev_err(host->hw_dev,
+					"Error occured while transferring data: 0x%X\n",
+					intr_status);
+			return -EPERM;
+		}
+		if (intr_status & data_ready_intr_mask) {
+			status = bcm2835_mci_read(host, SDHCI_PRESENT_STATE);
+			if ((status & data_ready_status_mask) == 0)
+				continue;
+			/*Clear latest int and transfer one block size of data*/
+			bcm2835_mci_write(host, SDHCI_INT_STATUS,
+					data_ready_intr_mask);
+			for (i = 0; i < data->blocksize; i += 4) {
+				read_write_func(host, p);
+				p++;
+				data_size -= 4;
+			}
+		}
+	} while ((intr_status & IRQSTAT_TC) == 0);
+
+	if (data_size != 0) {
+		if (data->flags & MMC_DATA_READ)
+			dev_err(host->hw_dev, "Error while reading:\n");
+		else
+			dev_err(host->hw_dev, "Error while writing:\n");
+
+		dev_err(host->hw_dev, "Transferred %d bytes of data, wanted %d\n",
+				(data->blocksize * data->blocks) - data_size,
+				data->blocksize * data->blocks);
+
+		dev_err(host->hw_dev, "Status: 0x%X, Interrupt: 0x%X\n",
+				bcm2835_mci_read(host, SDHCI_PRESENT_STATE),
+				bcm2835_mci_read(host, SDHCI_INT_STATUS));
+
+		return -EPERM;
+	}
+	return 0;
+}
+
+static u32 bcm2835_mci_wait_command_done(struct bcm2835_mci_host *host)
+{
+	u32 interrupt = 0;
+
+	while (true) {
+		interrupt = bcm2835_mci_read(
+				host, SDHCI_INT_STATUS);
+		if (interrupt & IRQSTAT_CIE)
+			return -EPERM;
+		if (interrupt & IRQSTAT_CC)
+			break;
+	}
+	return 0;
+}
+
+static void bcm2835_mci_reset_emmc(struct bcm2835_mci_host *host, u32 reset,
+		u32 wait_for)
+{
+	u32 ret;
+	u32 current = bcm2835_mci_read(host,
+			SDHCI_CLOCK_CONTROL__TIMEOUT_CONTROL__SOFTWARE_RESET);
+
+	bcm2835_mci_write(host,
+			SDHCI_CLOCK_CONTROL__TIMEOUT_CONTROL__SOFTWARE_RESET,
+			current | reset);
+
+	while (true) {
+		ret = bcm2835_mci_read(host,
+				SDHCI_CLOCK_CONTROL__TIMEOUT_CONTROL__SOFTWARE_RESET);
+		if (ret & wait_for)
+			continue;
+		break;
+	}
+}
+
+/**
+ * Process one command to the MCI card
+ * @param host MCI host
+ * @param cmd The command to process
+ * @param data The data to handle in the command (can be NULL)
+ * @return 0 on success, negative value else
+ */
+static int bcm2835_mci_request(struct mci_host *mci, struct mci_cmd *cmd,
+		struct mci_data *data) {
+	u32 command, block_data = 0, ret = 0;
+	u32 wait_inhibit_mask = PRSSTAT_CICHB | PRSSTAT_CIDHB;
+	struct bcm2835_mci_host *host = to_bcm2835_host(mci);
+
+	command = COMMAND_CMD(cmd->cmdidx);
+
+	if (cmd->resp_type != MMC_RSP_NONE) {
+		if (cmd->resp_type & MMC_RSP_136)
+			command |= COMMAND_RSPTYP_136;
+		else if (cmd->resp_type & MMC_RSP_BUSY)
+			command |= COMMAND_RSPTYP_48_BUSY;
+		else
+			command |= COMMAND_RSPTYP_48;
+		if (cmd->resp_type & MMC_RSP_CRC)
+			command |= COMMAND_CCCEN;
+	}
+	if (data != NULL) {
+		command |= COMMAND_DPSEL | TRANSFER_MODE_BCEN;
+
+		if (data->blocks > 1)
+			command |= TRANSFER_MODE_MSBSEL;
+
+		if (data->flags & MMC_DATA_READ)
+			command |= TRANSFER_MODE_DTDSEL;
+
+		block_data = (data->blocks << BLOCK_SHIFT);
+		block_data |= data->blocksize;
+	}
+
+	/* We shouldn't wait for data inihibit for stop commands, even
+	though they might use busy signaling */
+	if (cmd->cmdidx == MMC_CMD_STOP_TRANSMISSION)
+		wait_inhibit_mask = PRSSTAT_CICHB;
+
+	/*Wait for old command*/
+	while (bcm2835_mci_read(host, SDHCI_PRESENT_STATE)
+			& wait_inhibit_mask)
+		;
+
+	bcm2835_mci_write(host, SDHCI_INT_ENABLE, 0xFFFFFFFF);
+	bcm2835_mci_write(host, SDHCI_INT_STATUS, 0xFFFFFFFF);
+
+	bcm2835_mci_write(host, SDHCI_BLOCK_SIZE__BLOCK_COUNT, block_data);
+	bcm2835_mci_write(host, SDHCI_ARGUMENT, cmd->cmdarg);
+	bcm2835_mci_write(host, SDHCI_TRANSFER_MODE__COMMAND, command);
+
+	ret = bcm2835_mci_wait_command_done(host);
+	if (ret) {
+		dev_err(host->hw_dev, "Error while executing command %d\n",
+				cmd->cmdidx);
+		dev_err(host->hw_dev, "Status: 0x%X, Interrupt: 0x%X\n",
+				bcm2835_mci_read(host, SDHCI_PRESENT_STATE),
+				bcm2835_mci_read(host, SDHCI_INT_STATUS));
+	}
+	if (cmd->resp_type != 0 && ret != -1) {
+		int i = 0;
+
+		/* CRC is stripped so we need to do some shifting. */
+		if (cmd->resp_type & MMC_RSP_136) {
+			for (i = 0; i < 4; i++) {
+				cmd->response[i] = bcm2835_mci_read(
+					host,
+					SDHCI_RESPONSE_0 + (3 - i) * 4) << 8;
+				if (i != 3)
+					cmd->response[i] |=
+						readb((u32) (host->regs) +
+						SDHCI_RESPONSE_0 +
+						(3 - i) * 4 - 1);
+			}
+		} else {
+			cmd->response[0] = bcm2835_mci_read(
+					host, SDHCI_RESPONSE_0);
+		}
+		bcm2835_mci_write(host, SDHCI_INT_STATUS,
+				IRQSTAT_CC);
+	}
+
+	if (!ret && data)
+		ret = bcm2835_mci_transfer_data(host, cmd, data);
+
+	bcm2835_mci_write(host, SDHCI_INT_STATUS, 0xFFFFFFFF);
+	if (ret) {
+		bcm2835_mci_reset_emmc(host, CONTROL1_CMDRST,
+				CONTROL1_CMDRST);
+		bcm2835_mci_reset_emmc(host, CONTROL1_DATARST,
+				CONTROL1_DATARST);
+	}
+
+	return ret;
+}
+
+static u32 bcm2835_mci_get_clock_divider(struct bcm2835_mci_host *host,
+		u32 desired_hz)
+{
+	u32 div;
+	u32 clk_hz;
+
+	if (host->version >= SDHCI_SPEC_300) {
+		/* Version 3.00 divisors must be a multiple of 2. */
+		if (host->max_clock <= desired_hz)
+			div = 1;
+		else {
+			for (div = 2; div < MAX_CLK_DIVIDER_V3; div += 2) {
+				clk_hz = host->max_clock / div;
+				if (clk_hz <= desired_hz)
+					break;
+			}
+		}
+	} else {
+		/* Version 2.00 divisors must be a power of 2. */
+		for (div = 1; div < MAX_CLK_DIVIDER_V2; div *= 2) {
+			clk_hz = host->max_clock / div;
+			if (clk_hz <= desired_hz)
+				break;
+		}
+
+	}
+
+	/*Since setting lowest bit means divide by two, shift down*/
+	dev_dbg(host->hw_dev,
+			"Wanted %d hz, returning divider %d (%d) which yields %d hz\n",
+			desired_hz, div >> 1, div, host->max_clock / div);
+	twoticks_delay = ((2 * 1000000000) / (host->max_clock / div)) + 1;
+
+	div = div >> 1;
+	host->clock = desired_hz;
+	return div;
+}
+
+/**
+ * Setup the bus width and IO speed
+ * @param host MCI host
+ * @param bus_width New bus width value (1, 4 or 8)
+ * @param clock New clock in Hz (can be '0' to disable the clock)
+ */
+static void bcm2835_mci_set_ios(struct mci_host *mci, struct mci_ios *ios)
+{
+	u32 divider;
+	u32 divider_msb, divider_lsb;
+	u32 enable;
+	u32 current_val;
+
+	struct bcm2835_mci_host *host = to_bcm2835_host(mci);
+
+	current_val = bcm2835_mci_read(host,
+			SDHCI_HOST_CONTROL__POWER_CONTROL__BLOCK_GAP_CONTROL);
+
+	switch (ios->bus_width) {
+	case MMC_BUS_WIDTH_4:
+		bcm2835_mci_write(host,
+				SDHCI_HOST_CONTROL__POWER_CONTROL__BLOCK_GAP_CONTROL,
+				current_val | CONTROL0_4DATA);
+		host->bus_width = 1;
+		dev_dbg(host->hw_dev, "Changing bus width to 4\n");
+		break;
+	case MMC_BUS_WIDTH_1:
+		bcm2835_mci_write(host,
+				SDHCI_HOST_CONTROL__POWER_CONTROL__BLOCK_GAP_CONTROL,
+				current_val & ~CONTROL0_4DATA);
+		host->bus_width = 0;
+		dev_dbg(host->hw_dev, "Changing bus width to 1\n");
+		break;
+	default:
+		dev_warn(host->hw_dev, "Unsupported width received: %d\n",
+				ios->bus_width);
+		return;
+	}
+	if (ios->clock != host->clock && ios->clock != 0) {
+		bcm2835_mci_write(host,
+				SDHCI_CLOCK_CONTROL__TIMEOUT_CONTROL__SOFTWARE_RESET,
+				0x00);
+
+		if (ios->clock > 26000000) {
+			enable = bcm2835_mci_read(host,
+					SDHCI_HOST_CONTROL__POWER_CONTROL__BLOCK_GAP_CONTROL);
+			enable |= CONTROL0_HISPEED;
+			bcm2835_mci_write(host,
+					SDHCI_CLOCK_CONTROL__TIMEOUT_CONTROL__SOFTWARE_RESET,
+					enable);
+		}
+
+		divider = bcm2835_mci_get_clock_divider(host, ios->clock);
+		divider_msb = divider & 0x300;
+		divider_msb >>= CONTROL1_CLKLSB;
+		divider_lsb = divider & 0xFF;
+		enable = (divider_lsb << CONTROL1_CLKLSB);
+		enable |= (divider_msb << CONTROL1_CLKMSB);
+		enable |= CONTROL1_INTCLKENA | CONTROL1_TIMEOUT;
+
+		bcm2835_mci_write(host,
+				SDHCI_CLOCK_CONTROL__TIMEOUT_CONTROL__SOFTWARE_RESET,
+				enable);
+		while (true) {
+			u32 ret = bcm2835_mci_read(host,
+					SDHCI_CLOCK_CONTROL__TIMEOUT_CONTROL__SOFTWARE_RESET);
+			if (ret & CONTROL1_CLK_STABLE)
+				break;
+		}
+
+		enable |= CONTROL1_CLKENA;
+		bcm2835_mci_write(host,
+				SDHCI_CLOCK_CONTROL__TIMEOUT_CONTROL__SOFTWARE_RESET,
+				enable);
+
+		mdelay(100);
+
+		bcm2835_mci_reset_emmc(host, CONTROL1_CMDRST,
+				CONTROL1_CMDRST);
+		bcm2835_mci_reset_emmc(host, CONTROL1_DATARST,
+				CONTROL1_DATARST);
+
+		host->clock = ios->clock;
+	}
+	dev_dbg(host->hw_dev, "IO settings: bus width=%d, frequency=%u Hz\n",
+			host->bus_width, host->clock);
+}
+
+int bcm2835_mci_reset(struct mci_host *mci, struct device_d *mci_dev)
+{
+	struct bcm2835_mci_host *host;
+	u32 ret = 0;
+	u32 reset = CONTROL1_HOSTRST | CONTROL1_CMDRST | CONTROL1_DATARST;
+	u32 enable = 0;
+	u32 divider;
+	u32 divider_msb, divider_lsb;
+
+	host = to_bcm2835_host(mci);
+	divider = bcm2835_mci_get_clock_divider(host, MIN_FREQ);
+	divider_msb = divider & 0x300;
+	divider_msb = divider_msb >> CONTROL1_CLKLSB;
+	divider_lsb = divider & 0xFF;
+
+	enable = (divider_lsb << CONTROL1_CLKLSB);
+	enable |= (divider_msb << CONTROL1_CLKMSB);
+	enable |= CONTROL1_INTCLKENA | CONTROL1_TIMEOUT;
+
+	bcm2835_mci_reset_emmc(host, enable | reset, CONTROL1_HOSTRST);
+
+	bcm2835_mci_write(host,
+			SDHCI_HOST_CONTROL__POWER_CONTROL__BLOCK_GAP_CONTROL,
+			0x00);
+	bcm2835_mci_write(host, SDHCI_ACMD12_ERR__HOST_CONTROL2,
+			0x00);
+	bcm2835_mci_write(host,
+			SDHCI_CLOCK_CONTROL__TIMEOUT_CONTROL__SOFTWARE_RESET,
+			enable);
+	while (true) {
+		ret = bcm2835_mci_read(host,
+				SDHCI_CLOCK_CONTROL__TIMEOUT_CONTROL__SOFTWARE_RESET);
+		if (ret & CONTROL1_CLK_STABLE)
+			break;
+	}
+
+	enable |= CONTROL1_CLKENA;
+	bcm2835_mci_write(host,
+			SDHCI_CLOCK_CONTROL__TIMEOUT_CONTROL__SOFTWARE_RESET,
+			enable);
+
+	/*Delay atelast 74 clk cycles for card init*/
+	mdelay(100);
+
+	bcm2835_mci_write(host, SDHCI_INT_ENABLE,
+			0xFFFFFFFF);
+	bcm2835_mci_write(host, SDHCI_INT_STATUS,
+			0xFFFFFFFF);
+
+	/*Now write command 0 and see if we get response*/
+	bcm2835_mci_write(host, SDHCI_ARGUMENT, 0x0);
+	bcm2835_mci_write(host, SDHCI_TRANSFER_MODE__COMMAND, 0x0);
+	return bcm2835_mci_wait_command_done(host);
+}
+
+static u32 bcm2835_mci_get_emmc_clock(struct msg_get_clock_rate *clk_data)
+{
+	u32 val;
+	struct bcm2835_mbox_regs *regs =
+			(struct bcm2835_mbox_regs *) BCM2835_MBOX_PHYSADDR;
+
+	/*Read out old msg*/
+	while (true) {
+		val = readl(&regs->status);
+		if (val & BCM2835_MBOX_STATUS_RD_EMPTY)
+			break;
+		val = readl(&regs->read);
+	}
+
+	/*Check for ok to write*/
+	while (true) {
+		val = readl(&regs->status);
+		if (!(val & BCM2835_MBOX_STATUS_WR_FULL))
+			break;
+	}
+	val = BCM2835_MBOX_PROP_CHAN + ((u32) &clk_data->hdr);
+	writel(val, &regs->write);
+
+	while (true) {
+		/* Wait for the response */
+		while (true) {
+			val = readl(&regs->status);
+			if (!(val & BCM2835_MBOX_STATUS_RD_EMPTY))
+				break;
+		}
+
+		/* Read the response */
+		val = readl(&regs->read);
+		if ((val & 0x0F) == BCM2835_MBOX_PROP_CHAN)
+			break;
+	}
+	if ((val & ~0x0F) == ((u32) &clk_data->hdr))
+		if (clk_data->get_clock_rate.tag_hdr.val_len
+				& BCM2835_MBOX_TAG_VAL_LEN_RESPONSE)
+			return 1;
+	return 0;
+}
+
+static int bcm2835_mci_probe(struct device_d *hw_dev)
+{
+	struct bcm2835_mci_host *host;
+	struct msg_get_clock_rate *clk_data;
+
+	host = xzalloc(sizeof(*host));
+	host->mci.send_cmd = bcm2835_mci_request;
+	host->mci.set_ios = bcm2835_mci_set_ios;
+	host->mci.init = bcm2835_mci_reset;
+	host->mci.hw_dev = hw_dev;
+	host->hw_dev = hw_dev;
+
+	/* Allocate a buffer thats 16 bytes aligned in memory
+	 * Of the 32 bits address passed into the mbox 28 bits
+	 * are the address of the buffer, lower 4 bits is channel
+	 */
+	clk_data = memalign(16, sizeof(struct msg_get_clock_rate));
+	memset(clk_data, 0, sizeof(struct msg_get_clock_rate));
+	clk_data->hdr.buf_size = sizeof(struct msg_get_clock_rate);
+	clk_data->get_clock_rate.tag_hdr.tag = BCM2835_MBOX_TAG_GET_CLOCK_RATE;
+	clk_data->get_clock_rate.tag_hdr.val_buf_size =
+			sizeof(clk_data->get_clock_rate.body);
+	clk_data->get_clock_rate.tag_hdr.val_len =
+			sizeof(clk_data->get_clock_rate.body.req);
+	clk_data->get_clock_rate.body.req.clock_id = BCM2835_MBOX_CLOCK_ID_EMMC;
+
+	if (!bcm2835_mci_get_emmc_clock(clk_data)) {
+		dev_warn(host->hw_dev,
+				"Failed getting emmc clock, lets go anyway with 50MHz\n");
+		host->max_clock = 50000000;
+	} else {
+		host->max_clock = clk_data->get_clock_rate.body.resp.rate_hz;
+		dev_info(host->hw_dev, "Got emmc clock at %d Hz\n",
+				host->max_clock);
+	}
+
+	host->regs = dev_request_mem_region(hw_dev, 0);
+	if (host->regs == NULL) {
+		dev_err(host->hw_dev, "Failed request mem region, aborting...\n");
+		return -EBUSY;
+	}
+
+	host->mci.host_caps |= MMC_MODE_4BIT | MMC_MODE_HS | MMC_MODE_HS_52MHz;
+
+	host->mci.voltages = MMC_VDD_32_33 | MMC_VDD_33_34;
+
+	host->mci.f_min = MIN_FREQ;
+	host->mci.f_max = host->max_clock;
+
+	/*
+	 * The Arasan has a bugette whereby it may lose the content of
+	 * successive writes to registers that are within two SD-card clock
+	 * cycles of each other (a clock domain crossing problem).
+	 *
+	 * 1/MIN_FREQ is (max) time per tick of eMMC clock.
+	 * 2/MIN_FREQ is time for two ticks.
+	 * Multiply by 1000000000 to get nS per two ticks.
+	 * +1 for hack rounding.
+	 */
+
+	twoticks_delay = ((2 * 1000000000) / MIN_FREQ) + 1;
+
+	host->version = bcm2835_mci_read(
+			host, BCM2835_MCI_SLOTISR_VER);
+	host->version = (host->version >> 16) & 0xFF;
+	return mci_register(&host->mci);
+}
+
+static struct driver_d bcm2835_mci_driver = {
+	.name = "bcm2835_mci",
+	.probe = bcm2835_mci_probe,
+};
+
+static int bcm2835_mci_add(void)
+{
+	return platform_driver_register(&bcm2835_mci_driver);
+}
+coredevice_initcall(bcm2835_mci_add);