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authorSascha Hauer <s.hauer@pengutronix.de>2019-05-10 18:15:50 +0200
committerSascha Hauer <s.hauer@pengutronix.de>2019-05-10 18:15:50 +0200
commit066794f82b3355bd8302bdbb898569ee6fafcb0a (patch)
treedd4d3d166d60931d5dfab4898cb1affbbbd73612
parentbac01839b063697200d5b957b652da197b8f0b1d (diff)
parent9036d1db4d4a9a61bcda4871a5ce844d84d3d793 (diff)
downloadbarebox-066794f82b3355bd8302bdbb898569ee6fafcb0a.tar.gz
Merge branch 'for-next/mmc'
-rw-r--r--arch/arm/boards/raspberry-pi/rpi-common.c8
-rw-r--r--arch/arm/configs/rpi_defconfig2
-rw-r--r--arch/arm/dts/bcm2837-rpi-3.dts5
-rw-r--r--drivers/mci/Kconfig4
-rw-r--r--drivers/mci/Makefile1
-rw-r--r--drivers/mci/bcm2835-sdhost.c638
6 files changed, 652 insertions, 6 deletions
diff --git a/arch/arm/boards/raspberry-pi/rpi-common.c b/arch/arm/boards/raspberry-pi/rpi-common.c
index bc877f8..dd6bbd5 100644
--- a/arch/arm/boards/raspberry-pi/rpi-common.c
+++ b/arch/arm/boards/raspberry-pi/rpi-common.c
@@ -319,6 +319,14 @@ static int rpi_clock_init(void)
clkdev_add_physbase(clk, 0x20300000, NULL);
clkdev_add_physbase(clk, 0x3f300000, NULL);
+ clk = rpi_register_firmware_clock(BCM2835_MBOX_CLOCK_ID_CORE,
+ "bcm2835_sdhost");
+ if (IS_ERR(clk))
+ return PTR_ERR(clk);
+
+ clkdev_add_physbase(clk, 0x20202000, NULL);
+ clkdev_add_physbase(clk, 0x3f202000, NULL);
+
return 0;
}
postconsole_initcall(rpi_clock_init);
diff --git a/arch/arm/configs/rpi_defconfig b/arch/arm/configs/rpi_defconfig
index f167625..0ae0c42 100644
--- a/arch/arm/configs/rpi_defconfig
+++ b/arch/arm/configs/rpi_defconfig
@@ -66,12 +66,12 @@ CONFIG_SERIAL_AMBA_PL011=y
CONFIG_DRIVER_SERIAL_NS16550=y
CONFIG_MCI=y
CONFIG_MCI_BCM283X=y
+CONFIG_MCI_BCM283X_SDHOST=y
CONFIG_LED=y
CONFIG_LED_GPIO=y
CONFIG_LED_TRIGGERS=y
CONFIG_WATCHDOG=y
CONFIG_WATCHDOG_BCM2835=y
-CONFIG_PINCTRL=y
CONFIG_PINCTRL_BCM283X=y
CONFIG_REGULATOR=y
CONFIG_FS_EXT4=y
diff --git a/arch/arm/dts/bcm2837-rpi-3.dts b/arch/arm/dts/bcm2837-rpi-3.dts
index 5188361..420525b 100644
--- a/arch/arm/dts/bcm2837-rpi-3.dts
+++ b/arch/arm/dts/bcm2837-rpi-3.dts
@@ -11,10 +11,5 @@
};
&sdhci {
- pinctrl-0 = <&emmc_gpio48>;
- /delete-node/ wifi@1;
-};
-
-&sdhost {
status = "disabled";
};
diff --git a/drivers/mci/Kconfig b/drivers/mci/Kconfig
index 911cc0c..08c8c84 100644
--- a/drivers/mci/Kconfig
+++ b/drivers/mci/Kconfig
@@ -66,6 +66,10 @@ config MCI_BCM283X
bool "MCI support for BCM283X"
depends on ARCH_BCM283X
+config MCI_BCM283X_SDHOST
+ bool "BCM283X sdhost"
+ depends on ARCH_BCM283X
+
config MCI_DOVE
bool "Marvell Dove SDHCI"
depends on ARCH_DOVE
diff --git a/drivers/mci/Makefile b/drivers/mci/Makefile
index f6214c0..25a1d07 100644
--- a/drivers/mci/Makefile
+++ b/drivers/mci/Makefile
@@ -1,6 +1,7 @@
obj-$(CONFIG_MCI) += mci-core.o
obj-$(CONFIG_MCI_ATMEL) += atmel_mci.o
obj-$(CONFIG_MCI_BCM283X) += mci-bcm2835.o
+obj-$(CONFIG_MCI_BCM283X_SDHOST) += bcm2835-sdhost.o
obj-$(CONFIG_MCI_DOVE) += dove-sdhci.o
obj-$(CONFIG_MCI_IMX) += imx.o
obj-$(CONFIG_MCI_IMX_ESDHC) += imx-esdhc.o
diff --git a/drivers/mci/bcm2835-sdhost.c b/drivers/mci/bcm2835-sdhost.c
new file mode 100644
index 0000000..1d3a6c0
--- /dev/null
+++ b/drivers/mci/bcm2835-sdhost.c
@@ -0,0 +1,638 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * This code is ported from U-Boot by Lucas Stach <l.stach@pengutronix.de> and
+ * has the following contributors listed in the original license header:
+ * Alexander Graf <agraf@suse.de>
+ * Phil Elwell <phil@raspberrypi.org>
+ * Gellert Weisz
+ * Stephen Warren
+ * Oleksandr Tymoshenko
+ */
+
+#include <clock.h>
+#include <common.h>
+#include <driver.h>
+#include <init.h>
+#include <linux/clk.h>
+#include <linux/iopoll.h>
+#include <linux/log2.h>
+#include <mci.h>
+
+#define SDCMD 0x00 /* Command to SD card - 16 R/W */
+#define SDARG 0x04 /* Argument to SD card - 32 R/W */
+#define SDTOUT 0x08 /* Start value for timeout counter - 32 R/W */
+#define SDCDIV 0x0c /* Start value for clock divider - 11 R/W */
+#define SDRSP0 0x10 /* SD card response (31:0) - 32 R */
+#define SDRSP1 0x14 /* SD card response (63:32) - 32 R */
+#define SDRSP2 0x18 /* SD card response (95:64) - 32 R */
+#define SDRSP3 0x1c /* SD card response (127:96) - 32 R */
+#define SDHSTS 0x20 /* SD host status - 11 R/W */
+#define SDVDD 0x30 /* SD card power control - 1 R/W */
+#define SDEDM 0x34 /* Emergency Debug Mode - 13 R/W */
+#define SDHCFG 0x38 /* Host configuration - 2 R/W */
+#define SDHBCT 0x3c /* Host byte count (debug) - 32 R/W */
+#define SDDATA 0x40 /* Data to/from SD card - 32 R/W */
+#define SDHBLC 0x50 /* Host block count (SDIO/SDHC) - 9 R/W */
+
+#define SDCMD_NEW_FLAG 0x8000
+#define SDCMD_FAIL_FLAG 0x4000
+#define SDCMD_BUSYWAIT 0x800
+#define SDCMD_NO_RESPONSE 0x400
+#define SDCMD_LONG_RESPONSE 0x200
+#define SDCMD_WRITE_CMD 0x80
+#define SDCMD_READ_CMD 0x40
+#define SDCMD_CMD_MASK 0x3f
+
+#define SDCDIV_MAX_CDIV 0x7ff
+
+#define SDHSTS_BUSY_IRPT 0x400
+#define SDHSTS_BLOCK_IRPT 0x200
+#define SDHSTS_SDIO_IRPT 0x100
+#define SDHSTS_REW_TIME_OUT 0x80
+#define SDHSTS_CMD_TIME_OUT 0x40
+#define SDHSTS_CRC16_ERROR 0x20
+#define SDHSTS_CRC7_ERROR 0x10
+#define SDHSTS_FIFO_ERROR 0x08
+#define SDHSTS_DATA_FLAG 0x01
+
+#define SDHSTS_CLEAR_MASK (SDHSTS_BUSY_IRPT | \
+ SDHSTS_BLOCK_IRPT | \
+ SDHSTS_SDIO_IRPT | \
+ SDHSTS_REW_TIME_OUT | \
+ SDHSTS_CMD_TIME_OUT | \
+ SDHSTS_CRC16_ERROR | \
+ SDHSTS_CRC7_ERROR | \
+ SDHSTS_FIFO_ERROR)
+
+#define SDHSTS_TRANSFER_ERROR_MASK (SDHSTS_CRC7_ERROR | \
+ SDHSTS_CRC16_ERROR | \
+ SDHSTS_REW_TIME_OUT | \
+ SDHSTS_FIFO_ERROR)
+
+#define SDHSTS_ERROR_MASK (SDHSTS_CMD_TIME_OUT | \
+ SDHSTS_TRANSFER_ERROR_MASK)
+
+#define SDHCFG_BUSY_IRPT_EN BIT(10)
+#define SDHCFG_BLOCK_IRPT_EN BIT(8)
+#define SDHCFG_SDIO_IRPT_EN BIT(5)
+#define SDHCFG_DATA_IRPT_EN BIT(4)
+#define SDHCFG_SLOW_CARD BIT(3)
+#define SDHCFG_WIDE_EXT_BUS BIT(2)
+#define SDHCFG_WIDE_INT_BUS BIT(1)
+#define SDHCFG_REL_CMD_LINE BIT(0)
+
+#define SDVDD_POWER_OFF 0
+#define SDVDD_POWER_ON 1
+
+#define SDEDM_FORCE_DATA_MODE BIT(19)
+#define SDEDM_CLOCK_PULSE BIT(20)
+#define SDEDM_BYPASS BIT(21)
+
+#define SDEDM_FIFO_FILL_SHIFT 4
+#define SDEDM_FIFO_FILL_MASK 0x1f
+static u32 edm_fifo_fill(u32 edm)
+{
+ return (edm >> SDEDM_FIFO_FILL_SHIFT) & SDEDM_FIFO_FILL_MASK;
+}
+
+#define SDEDM_WRITE_THRESHOLD_SHIFT 9
+#define SDEDM_READ_THRESHOLD_SHIFT 14
+#define SDEDM_THRESHOLD_MASK 0x1f
+
+#define SDEDM_FSM_MASK 0xf
+#define SDEDM_FSM_IDENTMODE 0x0
+#define SDEDM_FSM_DATAMODE 0x1
+#define SDEDM_FSM_READDATA 0x2
+#define SDEDM_FSM_WRITEDATA 0x3
+#define SDEDM_FSM_READWAIT 0x4
+#define SDEDM_FSM_READCRC 0x5
+#define SDEDM_FSM_WRITECRC 0x6
+#define SDEDM_FSM_WRITEWAIT1 0x7
+#define SDEDM_FSM_POWERDOWN 0x8
+#define SDEDM_FSM_POWERUP 0x9
+#define SDEDM_FSM_WRITESTART1 0xa
+#define SDEDM_FSM_WRITESTART2 0xb
+#define SDEDM_FSM_GENPULSES 0xc
+#define SDEDM_FSM_WRITEWAIT2 0xd
+#define SDEDM_FSM_STARTPOWDOWN 0xf
+
+#define SDDATA_FIFO_WORDS 16
+
+#define FIFO_READ_THRESHOLD 4
+#define FIFO_WRITE_THRESHOLD 4
+#define SDDATA_FIFO_PIO_BURST 8
+
+#define SDHST_TIMEOUT_MAX_USEC 100000
+
+struct bcm2835_host {
+ struct mci_host mci;
+ void __iomem *regs;
+ struct clk *clk;
+};
+
+static inline struct bcm2835_host *to_bcm2835_host(struct mci_host *mci)
+{
+ return container_of(mci, struct bcm2835_host, mci);
+}
+
+static int bcm2835_sdhost_init(struct mci_host *mci, struct device_d *dev)
+{
+ struct bcm2835_host *host = to_bcm2835_host(mci);
+ u32 temp;
+
+ writel(SDVDD_POWER_OFF, host->regs + SDVDD);
+ writel(0, host->regs + SDCMD);
+ writel(0, host->regs + SDARG);
+ /* Set timeout to a big enough value so we don't hit it */
+ writel(0xf00000, host->regs + SDTOUT);
+ writel(0, host->regs + SDCDIV);
+ /* Clear status register */
+ writel(SDHSTS_CLEAR_MASK, host->regs + SDHSTS);
+ writel(0, host->regs + SDHCFG);
+ writel(0, host->regs + SDHBCT);
+ writel(0, host->regs + SDHBLC);
+
+ /* Limit fifo usage due to silicon bug */
+ temp = readl(host->regs + SDEDM);
+ temp &= ~((SDEDM_THRESHOLD_MASK << SDEDM_READ_THRESHOLD_SHIFT) |
+ (SDEDM_THRESHOLD_MASK << SDEDM_WRITE_THRESHOLD_SHIFT));
+ temp |= (FIFO_READ_THRESHOLD << SDEDM_READ_THRESHOLD_SHIFT) |
+ (FIFO_WRITE_THRESHOLD << SDEDM_WRITE_THRESHOLD_SHIFT);
+ writel(temp, host->regs + SDEDM);
+ /* Wait for FIFO threshold to populate */
+ mdelay(20);
+ writel(SDVDD_POWER_ON, host->regs + SDVDD);
+ /* Wait for all components to go through power on cycle */
+ mdelay(20);
+ writel(0, host->regs + SDHCFG);
+ writel(0, host->regs + SDCDIV);
+
+ return 0;
+}
+
+static int bcm2835_wait_transfer_complete(struct bcm2835_host *host)
+{
+ uint64_t start = get_time_ns();
+
+ while (1) {
+ u32 edm, fsm;
+
+ edm = readl(host->regs + SDEDM);
+ fsm = edm & SDEDM_FSM_MASK;
+
+ if ((fsm == SDEDM_FSM_IDENTMODE) ||
+ (fsm == SDEDM_FSM_DATAMODE))
+ break;
+
+ if ((fsm == SDEDM_FSM_READWAIT) ||
+ (fsm == SDEDM_FSM_WRITESTART1) ||
+ (fsm == SDEDM_FSM_READDATA)) {
+ writel(edm | SDEDM_FORCE_DATA_MODE,
+ host->regs + SDEDM);
+ break;
+ }
+
+ /* Error out after 1 second */
+ if (is_timeout(start, 1 * SECOND)) {
+ dev_err(host->mci.hw_dev,
+ "wait_transfer_complete - still waiting 1s\n");
+ return -ETIMEDOUT;
+ }
+ }
+
+ return 0;
+}
+
+static int bcm2835_transfer_block_pio(struct bcm2835_host *host,
+ struct mci_data *data, unsigned int block,
+ bool is_read)
+{
+ u32 *buf = is_read ? (u32 *)data->dest : (u32 *)data->src;
+ int copy_words = data->blocksize / sizeof(u32);
+ uint64_t start = get_time_ns();
+
+ if (data->blocksize % sizeof(u32))
+ return -EINVAL;
+
+ buf += (block * data->blocksize / sizeof(u32));
+
+ /* Copy all contents from/to the FIFO as far as it reaches. */
+ while (copy_words) {
+ int fifo_words;
+ u32 edm;
+
+ if (is_timeout(start, 100 * MSECOND)) {
+ dev_err(host->mci.hw_dev,
+ "transfer_block_pio timeout\n");
+ return -ETIMEDOUT;
+ }
+
+ edm = readl(host->regs + SDEDM);
+ if (is_read)
+ fifo_words = edm_fifo_fill(edm);
+ else
+ fifo_words = SDDATA_FIFO_WORDS - edm_fifo_fill(edm);
+
+ if (fifo_words > copy_words)
+ fifo_words = copy_words;
+
+ /* Copy current chunk to/from the FIFO */
+ while (fifo_words) {
+ if (is_read)
+ *(buf++) = readl(host->regs + SDDATA);
+ else
+ writel(*(buf++), host->regs + SDDATA);
+ fifo_words--;
+ copy_words--;
+ }
+ }
+
+ return 0;
+}
+
+static int bcm2835_transfer_pio(struct bcm2835_host *host,
+ struct mci_data *data)
+{
+ u32 sdhsts;
+ bool is_read = !!(data->flags & MMC_DATA_READ);
+ unsigned int block = 0;
+ int ret = 0;
+
+ while (block < data->blocks) {
+ ret = bcm2835_transfer_block_pio(host, data, block, is_read);
+ if (ret)
+ return ret;
+
+ sdhsts = readl(host->regs + SDHSTS);
+ if (sdhsts & (SDHSTS_CRC16_ERROR |
+ SDHSTS_CRC7_ERROR |
+ SDHSTS_FIFO_ERROR)) {
+ dev_err(host->mci.hw_dev,
+ "%s transfer error - HSTS %08x\n",
+ is_read ? "read" : "write", sdhsts);
+ ret = -EILSEQ;
+ } else if ((sdhsts & (SDHSTS_CMD_TIME_OUT |
+ SDHSTS_REW_TIME_OUT))) {
+ dev_err(host->mci.hw_dev,
+ "%s timeout error - HSTS %08x\n",
+ is_read ? "read" : "write", sdhsts);
+ ret = -ETIMEDOUT;
+ }
+ block++;
+ }
+
+ return ret;
+}
+
+static u32 bcm2835_read_wait_sdcmd(struct bcm2835_host *host)
+{
+ u32 value;
+ int ret;
+ int timeout_us = SDHST_TIMEOUT_MAX_USEC;
+
+ ret = readl_poll_timeout(host->regs + SDCMD, value,
+ !(value & SDCMD_NEW_FLAG), timeout_us);
+ if (ret == -ETIMEDOUT)
+ dev_err(host->mci.hw_dev, "%s: timeout (%d us)\n",
+ __func__, timeout_us);
+
+ return value;
+}
+
+static int bcm2835_send_command(struct bcm2835_host *host, struct mci_cmd *cmd,
+ struct mci_data *data)
+{
+ u32 sdcmd, sdhsts;
+
+ if ((cmd->resp_type & MMC_RSP_136) && (cmd->resp_type & MMC_RSP_BUSY)) {
+ dev_err(host->mci.hw_dev, "unsupported response type!\n");
+ return -EINVAL;
+ }
+
+ sdcmd = bcm2835_read_wait_sdcmd(host);
+ if (sdcmd & SDCMD_NEW_FLAG) {
+ dev_err(host->mci.hw_dev, "previous command never completed.\n");
+ return -EBUSY;
+ }
+
+ /* Clear any error flags */
+ sdhsts = readl(host->regs + SDHSTS);
+ if (sdhsts & SDHSTS_ERROR_MASK)
+ writel(sdhsts, host->regs + SDHSTS);
+
+ if (data) {
+ writel(data->blocksize, host->regs + SDHBCT);
+ writel(data->blocks, host->regs + SDHBLC);
+ }
+
+ writel(cmd->cmdarg, host->regs + SDARG);
+
+ sdcmd = cmd->cmdidx & SDCMD_CMD_MASK;
+
+ if (!(cmd->resp_type & MMC_RSP_PRESENT)) {
+ sdcmd |= SDCMD_NO_RESPONSE;
+ } else {
+ if (cmd->resp_type & MMC_RSP_136)
+ sdcmd |= SDCMD_LONG_RESPONSE;
+ if (cmd->resp_type & MMC_RSP_BUSY)
+ sdcmd |= SDCMD_BUSYWAIT;
+ }
+
+ if (data) {
+ if (data->flags & MMC_DATA_WRITE)
+ sdcmd |= SDCMD_WRITE_CMD;
+ if (data->flags & MMC_DATA_READ)
+ sdcmd |= SDCMD_READ_CMD;
+ }
+
+ writel(sdcmd | SDCMD_NEW_FLAG, host->regs + SDCMD);
+
+ return 0;
+}
+
+static int bcm2835_finish_command(struct bcm2835_host *host,
+ struct mci_cmd *cmd)
+{
+ u32 sdcmd;
+ int ret = 0;
+
+ sdcmd = bcm2835_read_wait_sdcmd(host);
+
+ /* Check for errors */
+ if (sdcmd & SDCMD_NEW_FLAG) {
+ dev_err(host->mci.hw_dev, "command never completed.\n");
+ return -EIO;
+ } else if (sdcmd & SDCMD_FAIL_FLAG) {
+ u32 sdhsts = readl(host->regs + SDHSTS);
+
+ /* Clear the errors */
+ writel(SDHSTS_ERROR_MASK, host->regs + SDHSTS);
+
+ if (!(sdhsts & SDHSTS_CRC7_ERROR) ||
+ (cmd->cmdidx != MMC_CMD_SEND_OP_COND)) {
+ if (sdhsts & SDHSTS_CMD_TIME_OUT) {
+ ret = -ETIMEDOUT;
+ } else {
+ dev_err(host->mci.hw_dev,
+ "unexpected command %d error\n",
+ cmd->cmdidx);
+ ret = -EILSEQ;
+ }
+
+ return ret;
+ }
+ }
+
+ if (cmd->resp_type & MMC_RSP_PRESENT) {
+ if (cmd->resp_type & MMC_RSP_136) {
+ int i;
+
+ for (i = 0; i < 4; i++) {
+ cmd->response[3 - i] =
+ readl(host->regs + SDRSP0 + i * 4);
+ }
+ } else {
+ cmd->response[0] = readl(host->regs + SDRSP0);
+ }
+ }
+
+ return ret;
+}
+
+static int bcm2835_check_cmd_error(struct bcm2835_host *host, u32 intmask)
+{
+ int ret = -EINVAL;
+
+ if (!(intmask & SDHSTS_ERROR_MASK))
+ return 0;
+
+ dev_err(host->mci.hw_dev, "sdhost_busy_irq: intmask %08x\n", intmask);
+ if (intmask & SDHSTS_CRC7_ERROR) {
+ ret = -EILSEQ;
+ } else if (intmask & (SDHSTS_CRC16_ERROR |
+ SDHSTS_FIFO_ERROR)) {
+ ret = -EILSEQ;
+ } else if (intmask & (SDHSTS_REW_TIME_OUT | SDHSTS_CMD_TIME_OUT)) {
+ ret = -ETIMEDOUT;
+ }
+
+ return ret;
+}
+
+static int bcm2835_check_data_error(struct bcm2835_host *host, u32 intmask)
+{
+ int ret = 0;
+
+ if (intmask & (SDHSTS_CRC16_ERROR | SDHSTS_FIFO_ERROR))
+ ret = -EILSEQ;
+ if (intmask & SDHSTS_REW_TIME_OUT)
+ ret = -ETIMEDOUT;
+
+ if (ret)
+ dev_err(host->mci.hw_dev, "data error %d\n", ret);
+
+ return ret;
+}
+
+static int bcm2835_transmit(struct bcm2835_host *host, struct mci_cmd *cmd,
+ struct mci_data *data)
+{
+ u32 intmask = readl(host->regs + SDHSTS);
+ int ret;
+
+ /* Check for errors */
+ if (data) {
+ ret = bcm2835_check_data_error(host, intmask);
+ if (ret)
+ return ret;
+ }
+
+ ret = bcm2835_check_cmd_error(host, intmask);
+ if (ret)
+ return ret;
+
+ /* Handle wait for busy end */
+ if ((cmd->resp_type & MMC_RSP_BUSY) &&
+ (intmask & SDHSTS_BUSY_IRPT)) {
+ writel(SDHSTS_BUSY_IRPT, host->regs + SDHSTS);
+ bcm2835_finish_command(host, cmd);
+ }
+
+ /* Handle PIO data transfer */
+ if (data) {
+ ret = bcm2835_transfer_pio(host, data);
+ if (ret)
+ return ret;
+ /* Transfer successful: wait for command to complete for real */
+ ret = bcm2835_wait_transfer_complete(host);
+ }
+
+ return ret;
+}
+
+static void bcm2835_set_clock(struct bcm2835_host *host, unsigned int clock)
+{
+ int div;
+
+ /* The SDCDIV register has 11 bits, and holds (div - 2). But
+ * in data mode the max is 50MHz without a minimum, and only
+ * the bottom 3 bits are used. Since the switch over is
+ * automatic (unless we have marked the card as slow...),
+ * chosen values have to make sense in both modes. Ident mode
+ * must be 100-400KHz, so can range check the requested
+ * clock. CMD15 must be used to return to data mode, so this
+ * can be monitored.
+ *
+ * clock 250MHz -> 0->125MHz, 1->83.3MHz, 2->62.5MHz, 3->50.0MHz
+ * 4->41.7MHz, 5->35.7MHz, 6->31.3MHz, 7->27.8MHz
+ *
+ * 623->400KHz/27.8MHz
+ * reset value (507)->491159/50MHz
+ *
+ * BUT, the 3-bit clock divisor in data mode is too small if
+ * the core clock is higher than 250MHz, so instead use the
+ * SLOW_CARD configuration bit to force the use of the ident
+ * clock divisor at all times.
+ */
+
+ if (clock < 100000) {
+ /* Can't stop the clock, but make it as slow as possible
+ * to show willing
+ */
+ writel(SDCDIV_MAX_CDIV, host->regs + SDCDIV);
+ return;
+ }
+
+ div = host->mci.f_max / clock;
+ if (div < 2)
+ div = 2;
+ if ((host->mci.f_max / div) > clock)
+ div++;
+ div -= 2;
+
+ if (div > SDCDIV_MAX_CDIV)
+ div = SDCDIV_MAX_CDIV;
+
+ clock = host->mci.f_max / (div + 2);
+
+ writel(div, host->regs + SDCDIV);
+
+ /* Set the timeout to 500ms */
+ writel(clock / 2, host->regs + SDTOUT);
+}
+
+static int bcm2835_send_cmd(struct mci_host *mci, struct mci_cmd *cmd,
+ struct mci_data *data)
+{
+ struct bcm2835_host *host = to_bcm2835_host(mci);
+ u32 edm, fsm;
+ int ret = 0;
+
+ if (data && !is_power_of_2(data->blocksize)) {
+ dev_err(mci->hw_dev, "unsupported block size (%d bytes)\n",
+ data->blocksize);
+ return -EINVAL;
+ }
+
+ edm = readl(host->regs + SDEDM);
+ fsm = edm & SDEDM_FSM_MASK;
+
+ if ((fsm != SDEDM_FSM_IDENTMODE) &&
+ (fsm != SDEDM_FSM_DATAMODE) &&
+ (cmd->cmdidx != MMC_CMD_STOP_TRANSMISSION)) {
+ dev_err(mci->hw_dev,
+ "previous command (%d) not complete (EDM %08x)\n",
+ readl(host->regs + SDCMD) & SDCMD_CMD_MASK, edm);
+
+ return -EILSEQ;
+ }
+
+ ret = bcm2835_send_command(host, cmd, data);
+ if (ret)
+ return ret;
+
+ if (!(cmd->resp_type & MMC_RSP_BUSY)) {
+ ret = bcm2835_finish_command(host, cmd);
+ if (ret)
+ return ret;
+ }
+
+ /* Wait for completion of busy signal or data transfer */
+ if ((cmd->resp_type & MMC_RSP_BUSY) || data)
+ ret = bcm2835_transmit(host, cmd, data);
+
+ return ret;
+}
+
+static void bcm2835_set_ios(struct mci_host *mci, struct mci_ios *ios)
+{
+ struct bcm2835_host *host = to_bcm2835_host(mci);
+ u32 hcfg = SDHCFG_WIDE_INT_BUS | SDHCFG_SLOW_CARD;
+
+ if (ios->clock)
+ bcm2835_set_clock(host, ios->clock);
+
+ /* set bus width */
+ if (ios->bus_width == MMC_BUS_WIDTH_4)
+ hcfg |= SDHCFG_WIDE_EXT_BUS;
+
+ writel(hcfg, host->regs + SDHCFG);
+}
+
+static int bcm2835_sdhost_detect(struct device_d *dev)
+{
+ struct bcm2835_host *host = dev->priv;
+
+ return mci_detect_card(&host->mci);
+}
+
+static int bcm2835_sdhost_probe(struct device_d *dev)
+{
+ struct bcm2835_host *host;
+ struct resource *iores;
+ struct mci_host *mci;
+
+ host = xzalloc(sizeof(*host));
+ mci = &host->mci;
+
+ host->clk = clk_get(dev, NULL);
+ if (IS_ERR(host->clk))
+ return PTR_ERR(host->clk);
+
+ iores = dev_request_mem_resource(dev, 0);
+ if (IS_ERR(iores)) {
+ dev_err(dev, "could not get iomem region\n");
+ return PTR_ERR(iores);
+ }
+ host->regs = IOMEM(iores->start);
+
+ mci->hw_dev = dev;
+ mci->f_max = clk_get_rate(host->clk);
+ mci->f_min = mci->f_max / SDCDIV_MAX_CDIV;
+ mci->voltages = MMC_VDD_32_33 | MMC_VDD_33_34;
+ mci->host_caps |= MMC_CAP_MMC_HIGHSPEED | MMC_CAP_MMC_HIGHSPEED_52MHZ |
+ MMC_CAP_SD_HIGHSPEED;
+
+ mci->init = bcm2835_sdhost_init;
+ mci->set_ios = bcm2835_set_ios;
+ mci->send_cmd = bcm2835_send_cmd;
+
+ dev->priv = host;
+ dev->detect = bcm2835_sdhost_detect,
+
+ mci_of_parse(mci);
+
+ return mci_register(mci);
+}
+
+static __maybe_unused struct of_device_id bcm2835_sdhost_compatible[] = {
+ { .compatible = "brcm,bcm2835-sdhost" },
+ { /* sentinel */ }
+};
+
+static struct driver_d bcm2835_sdhost_driver = {
+ .name = "bcm2835-sdhost",
+ .probe = bcm2835_sdhost_probe,
+ .of_compatible = DRV_OF_COMPAT(bcm2835_sdhost_compatible),
+};
+device_platform_driver(bcm2835_sdhost_driver);