[PATCH] Added sd driver for bcm2835 (Raspberry PI)
wilhelm
wilhelm.lundgren at gmail.com
Fri May 10 02:00:46 EDT 2013
Replaced defines according to sdhci.h
---
arch/arm/mach-bcm2835/core.c | 1 +
drivers/mci/Kconfig | 4 +
drivers/mci/Makefile | 1 +
drivers/mci/mci-bcm2835.c | 591 +++++++++++++++++++++++++++++++++++++++++++
drivers/mci/mci-bcm2835.h | 73 ++++++
5 files changed, 670 insertions(+)
create mode 100644 drivers/mci/mci-bcm2835.c
create mode 100644 drivers/mci/mci-bcm2835.h
diff --git a/arch/arm/mach-bcm2835/core.c b/arch/arm/mach-bcm2835/core.c
index f44ecd5..906e434 100644
--- a/arch/arm/mach-bcm2835/core.c
+++ b/arch/arm/mach-bcm2835/core.c
@@ -70,6 +70,7 @@ static int bcm2835_dev_init(void)
{
add_generic_device("bcm2835-gpio", 0, NULL, BCM2835_GPIO_BASE, 0xB0, IORESOURCE_MEM, NULL);
add_generic_device("bcm2835-cs", DEVICE_ID_SINGLE, NULL, BCM2835_ST_BASE, 0x1C, IORESOURCE_MEM, NULL);
+ add_generic_device("bcm2835_mci", 0, NULL, BCM2835_EMMC_BASE, 0xFC, IORESOURCE_MEM, NULL);
return 0;
}
coredevice_initcall(bcm2835_dev_init);
diff --git a/drivers/mci/Kconfig b/drivers/mci/Kconfig
index 9558f28..52cb303 100644
--- a/drivers/mci/Kconfig
+++ b/drivers/mci/Kconfig
@@ -45,6 +45,10 @@ config MCI_S3C
Enable this entry to add support to read and write SD cards on a
Samsung S3C24xx based system.
+config MCI_BCM2835
+ bool "MCI support for BCM2835"
+ depends on ARCH_BCM2835
+
config MCI_IMX
bool "i.MX"
depends on ARCH_IMX27 || ARCH_IMX31
diff --git a/drivers/mci/Makefile b/drivers/mci/Makefile
index d46d5f5..263f23a 100644
--- a/drivers/mci/Makefile
+++ b/drivers/mci/Makefile
@@ -8,3 +8,4 @@ obj-$(CONFIG_MFD_TWL6030) += twl6030.o
obj-$(CONFIG_MCI_PXA) += pxamci.o
obj-$(CONFIG_MCI_ATMEL) += atmel_mci.o
obj-$(CONFIG_MCI_SPI) += mci_spi.o
+obj-$(CONFIG_MCI_BCM2835) += mci-bcm2835.o
diff --git a/drivers/mci/mci-bcm2835.c b/drivers/mci/mci-bcm2835.c
new file mode 100644
index 0000000..b76f134
--- /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 at 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(®s->status);
+ if (val & BCM2835_MBOX_STATUS_RD_EMPTY)
+ break;
+ val = readl(®s->read);
+ }
+
+ /*Check for ok to write*/
+ while (true) {
+ val = readl(®s->status);
+ if (!(val & BCM2835_MBOX_STATUS_WR_FULL))
+ break;
+ }
+ val = BCM2835_MBOX_PROP_CHAN + ((u32) &clk_data->hdr);
+ writel(val, ®s->write);
+
+ while (true) {
+ /* Wait for the response */
+ while (true) {
+ val = readl(®s->status);
+ if (!(val & BCM2835_MBOX_STATUS_RD_EMPTY))
+ break;
+ }
+
+ /* Read the response */
+ val = readl(®s->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);
diff --git a/drivers/mci/mci-bcm2835.h b/drivers/mci/mci-bcm2835.h
new file mode 100644
index 0000000..4158a18
--- /dev/null
+++ b/drivers/mci/mci-bcm2835.h
@@ -0,0 +1,73 @@
+#define BCM2835_MCI_SLOTISR_VER 0xfc
+
+#define MIN_FREQ 400000
+#define BLOCK_SHIFT 16
+
+#define SDHCI_SPEC_100 0
+#define SDHCI_SPEC_200 1
+#define SDHCI_SPEC_300 2
+
+#define CONTROL0_HISPEED (1 << 2)
+#define CONTROL0_4DATA (1 << 1)
+
+#define CONTROL1_DATARST (1 << 26)
+#define CONTROL1_CMDRST (1 << 25)
+#define CONTROL1_HOSTRST (1 << 24)
+#define CONTROL1_CLKSELPROG (1 << 5)
+#define CONTROL1_CLKENA (1 << 2)
+#define CONTROL1_CLK_STABLE (1 << 1)
+#define CONTROL1_INTCLKENA (1 << 0)
+#define CONTROL1_CLKMSB 6
+#define CONTROL1_CLKLSB 8
+#define CONTROL1_TIMEOUT (0x0E << 16)
+
+#define MAX_CLK_DIVIDER_V3 2046
+#define MAX_CLK_DIVIDER_V2 256
+
+/*this is only for mbox comms*/
+#define BCM2835_MBOX_PHYSADDR 0x2000b880
+#define BCM2835_MBOX_TAG_GET_CLOCK_RATE 0x00030002
+#define BCM2835_MBOX_CLOCK_ID_EMMC 1
+#define BCM2835_MBOX_STATUS_WR_FULL 0x80000000
+#define BCM2835_MBOX_STATUS_RD_EMPTY 0x40000000
+#define BCM2835_MBOX_PROP_CHAN 8
+#define BCM2835_MBOX_TAG_VAL_LEN_RESPONSE 0x80000000
+
+struct bcm2835_mbox_regs {
+ u32 read;
+ u32 rsvd0[5];
+ u32 status;
+ u32 config;
+ u32 write;
+};
+
+
+struct bcm2835_mbox_hdr {
+ u32 buf_size;
+ u32 code;
+};
+
+struct bcm2835_mbox_tag_hdr {
+ u32 tag;
+ u32 val_buf_size;
+ u32 val_len;
+};
+
+struct bcm2835_mbox_tag_get_clock_rate {
+ struct bcm2835_mbox_tag_hdr tag_hdr;
+ union {
+ struct {
+ u32 clock_id;
+ } req;
+ struct {
+ u32 clock_id;
+ u32 rate_hz;
+ } resp;
+ } body;
+};
+
+struct msg_get_clock_rate {
+ struct bcm2835_mbox_hdr hdr;
+ struct bcm2835_mbox_tag_get_clock_rate get_clock_rate;
+ u32 end_tag;
+};
--
1.8.2.2
More information about the barebox
mailing list