[RFC 1/5] bcm2835-mmc: driver for Arasan eMMC IP
Piotr Król
piotr.krol at 3mdeb.com
Tue Oct 28 17:00:11 PDT 2014
This is driver for Arasan External Mass Media Controller provided in
Raspberry Pi single board computer.
Based on Gellert Weisz <gellert at raspberrypi.org> work.
Signed-off-by: Piotr Król <piotr.krol at 3mdeb.com>
---
drivers/mmc/host/Kconfig | 29 +
drivers/mmc/host/Makefile | 1 +
drivers/mmc/host/bcm2835-mmc.c | 1449 ++++++++++++++++++++++++++++++++++++++++
3 files changed, 1479 insertions(+)
create mode 100644 drivers/mmc/host/bcm2835-mmc.c
diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig
index 451135822464..c5e5a730cb60 100644
--- a/drivers/mmc/host/Kconfig
+++ b/drivers/mmc/host/Kconfig
@@ -302,6 +302,35 @@ config MMC_SDHCI_ST
If you have a controller with this interface, say Y or M here.
If unsure, say N.
+config MMC_BCM2835
+ tristate "MMC support on BCM2835"
+ depends on ARCH_BCM2835
+ help
+ This selects the MMC Interface on BCM2835.
+
+ If you have a controller with this interface, say Y or M here.
+
+ If unsure, say N.
+
+config MMC_BCM2835_DMA
+ bool "DMA support on BCM2835 Arasan controller"
+ depends on MMC_BCM2835
+ help
+ Enable DMA support on the Arasan SDHCI controller in Broadcom 2708
+ based chips.
+
+ If unsure, say N.
+
+config MMC_BCM2835_PIO_DMA_BARRIER
+ int "Block count limit for PIO transfers"
+ depends on MMC_BCM2835 && MMC_BCM2835_DMA
+ range 0 256
+ default 2
+ help
+ The inclusive limit in bytes under which PIO will be used instead of DMA
+
+ If unsure, say 2 here.
+
config MMC_OMAP
tristate "TI OMAP Multimedia Card Interface support"
depends on ARCH_OMAP
diff --git a/drivers/mmc/host/Makefile b/drivers/mmc/host/Makefile
index f211eede8db5..cf1c7300524b 100644
--- a/drivers/mmc/host/Makefile
+++ b/drivers/mmc/host/Makefile
@@ -67,6 +67,7 @@ obj-$(CONFIG_MMC_SDHCI_OF_ESDHC) += sdhci-of-esdhc.o
obj-$(CONFIG_MMC_SDHCI_OF_HLWD) += sdhci-of-hlwd.o
obj-$(CONFIG_MMC_SDHCI_BCM_KONA) += sdhci-bcm-kona.o
obj-$(CONFIG_MMC_SDHCI_BCM2835) += sdhci-bcm2835.o
+obj-$(CONFIG_MMC_BCM2835) += bcm2835-mmc.o
obj-$(CONFIG_MMC_SDHCI_MSM) += sdhci-msm.o
obj-$(CONFIG_MMC_SDHCI_ST) += sdhci-st.o
diff --git a/drivers/mmc/host/bcm2835-mmc.c b/drivers/mmc/host/bcm2835-mmc.c
new file mode 100644
index 000000000000..621506a91efb
--- /dev/null
+++ b/drivers/mmc/host/bcm2835-mmc.c
@@ -0,0 +1,1449 @@
+/*
+ * BCM2835 MMC host driver.
+ *
+ * Authors: Piotr Król <piotr.krol at 3mdeb.com>
+ * Gellert Weisz <gellert at raspberrypi.org>
+ * Copyright 2014
+ *
+ * Based on:
+ * sdhci-bcm2708.c by Broadcom
+ * sdhci-bcm2835.c by Stephen Warren and Oleksandr Tymoshenko
+ * sdhci.c and sdhci-pci.c by Pierre Ossman
+ *
+ * 22/10/2014 Piotr Król checkpatch cleanup
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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, see <http://www.gnu.org/licenses/>.
+ */
+
+#define DRIVER_NAME "bcm2835-mmc"
+
+#ifndef CONFIG_MMC_BCM2835_DMA
+#define FORCE_PIO
+#endif
+
+
+/* the inclusive limit in bytes under which PIO will be used instead of DMA */
+#ifdef CONFIG_MMC_BCM2835_PIO_DMA_BARRIER
+#define PIO_DMA_BARRIER CONFIG_MMC_BCM2835_PIO_DMA_BARRIER
+#else
+#define PIO_DMA_BARRIER 00
+#endif
+
+#define MIN_FREQ 400000
+#define TIMEOUT_VAL 0xE
+#define BCM2835_SDHCI_WRITE_DELAY(f) (((2 * 1000000) / f) + 1)
+
+/* FIXME: Needs IOMMU support */
+#define BCM2835_VCMMU_SHIFT 0x5E000000
+
+#include <linux/blkdev.h>
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/dma-mapping.h>
+#include <linux/dmaengine.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/mmc/host.h>
+#include <linux/mmc/mmc.h>
+#include <linux/mmc/sd.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/of_dma.h>
+#include <linux/of_irq.h>
+#include <linux/platform_device.h>
+#include <linux/scatterlist.h>
+
+#include "sdhci.h"
+
+
+struct bcm2835_host {
+ spinlock_t lock;
+ struct tasklet_struct finish_tasklet; /* Tasklet structures */
+ struct timer_list timer; /* Timer for timeouts */
+ struct sg_mapping_iter sg_miter; /* SG state for PIO */
+
+ struct mmc_request *mrq; /* Current request */
+ struct mmc_command *cmd; /* Current command */
+ struct mmc_data *data; /* Current data request */
+ struct mmc_host *mmc;
+
+ unsigned int max_clk; /* Max possible freq */
+ unsigned int timeout_clk; /* Timeout freq (KHz) */
+ unsigned int clk_mul; /* Clock Muliplier value */
+ unsigned int blocks; /* remaining PIO blocks */
+ unsigned int data_early:1; /* Data finished before cmd */
+ void __iomem *ioaddr;
+ u32 phys_addr;
+ u32 timeout;
+ u32 ier; /* cached registers */
+ u32 thread_isr;
+ u32 shadow;
+ int clock; /* Current clock speed */
+ int irq; /* Device IRQ */
+ u8 pwr; /* Current voltage */
+
+ /* Waitqueue for Buffer Read Ready IRQ */
+ wait_queue_head_t buf_ready_int;
+
+ /*DMA part*/
+ struct dma_chan *dma_chan_rx; /* DMA channel for reads */
+ struct dma_chan *dma_chan_tx; /* DMA channel for writes */
+ struct dma_async_tx_descriptor *tx_desc; /* descriptor */
+ bool have_dma;
+ bool use_dma;
+
+ int max_delay; /* maximum length of time spent waiting */
+ int flags; /* Host attributes */
+#define SDHCI_USE_SDMA (1<<0) /* Host is SDMA capable */
+#define SDHCI_USE_ADMA (1<<1) /* Host is ADMA capable */
+#define SDHCI_REQ_USE_DMA (1<<2) /* Use DMA for this req. */
+#define SDHCI_DEVICE_DEAD (1<<3) /* Device unresponsive */
+#define SDHCI_AUTO_CMD12 (1<<6) /* Auto CMD12 support */
+#define SDHCI_AUTO_CMD23 (1<<7) /* Auto CMD23 support */
+#define SDHCI_PV_ENABLED (1<<8) /* Preset value enabled */
+#define SDHCI_SDIO_IRQ_ENABLED (1<<9) /* SDIO irq enabled */
+#define SDHCI_USE_PLATDMA (1<<12) /* Host uses 3rd party DMA */
+};
+
+
+static inline void bcm2835_mmc_writel(struct bcm2835_host *host, u32 val,
+ int reg)
+{
+ writel(val, host->ioaddr + reg);
+ udelay(BCM2835_SDHCI_WRITE_DELAY(max(host->clock, MIN_FREQ)));
+}
+
+static inline void mmc_raw_writel(struct bcm2835_host *host, u32 val, int reg)
+{
+ writel(val, host->ioaddr + reg);
+}
+
+static inline u32 bcm2835_mmc_readl(struct bcm2835_host *host, int reg)
+{
+ return readl(host->ioaddr + reg);
+}
+
+static inline void bcm2835_mmc_writew(struct bcm2835_host *host, u16 val,
+ int reg)
+{
+ u32 oldval = (reg == SDHCI_COMMAND) ? host->shadow :
+ bcm2835_mmc_readl(host, reg & ~3);
+ u32 word_num = (reg >> 1) & 1;
+ u32 word_shift = word_num * 16;
+ u32 mask = 0xffff << word_shift;
+ u32 newval = (oldval & ~mask) | (val << word_shift);
+
+ if (reg == SDHCI_TRANSFER_MODE)
+ host->shadow = newval;
+ else
+ bcm2835_mmc_writel(host, newval, reg & ~3);
+
+}
+
+static inline void bcm2835_mmc_writeb(struct bcm2835_host *host, u8 val,
+ int reg)
+{
+ u32 oldval = bcm2835_mmc_readl(host, reg & ~3);
+ u32 byte_num = reg & 3;
+ u32 byte_shift = byte_num * 8;
+ u32 mask = 0xff << byte_shift;
+ u32 newval = (oldval & ~mask) | (val << byte_shift);
+
+ bcm2835_mmc_writel(host, newval, reg & ~3);
+}
+
+
+static inline u16 bcm2835_mmc_readw(struct bcm2835_host *host, int reg)
+{
+ u32 val = bcm2835_mmc_readl(host, (reg & ~3));
+ u32 word_num = (reg >> 1) & 1;
+ u32 word_shift = word_num * 16;
+ u32 word = (val >> word_shift) & 0xffff;
+
+ return word;
+}
+
+static inline u8 bcm2835_mmc_readb(struct bcm2835_host *host, int reg)
+{
+ u32 val = bcm2835_mmc_readl(host, (reg & ~3));
+ u32 byte_num = reg & 3;
+ u32 byte_shift = byte_num * 8;
+ u32 byte = (val >> byte_shift) & 0xff;
+
+ return byte;
+}
+
+static void bcm2835_mmc_unsignal_irqs(struct bcm2835_host *host, u32 clear)
+{
+ u32 ier;
+
+ ier = bcm2835_mmc_readl(host, SDHCI_SIGNAL_ENABLE);
+ ier &= ~clear;
+ /* change which requests generate IRQs - makes no difference to
+ the content of SDHCI_INT_STATUS, or the need to acknowledge IRQs */
+ bcm2835_mmc_writel(host, ier, SDHCI_SIGNAL_ENABLE);
+}
+
+static void bcm2835_mmc_reset(struct bcm2835_host *host, u8 mask)
+{
+ unsigned long timeout;
+
+ bcm2835_mmc_writeb(host, mask, SDHCI_SOFTWARE_RESET);
+
+ if (mask & SDHCI_RESET_ALL)
+ host->clock = 0;
+
+ /* Wait max 100 ms */
+ timeout = 100;
+
+ /* hw clears the bit when it's done */
+ while (bcm2835_mmc_readb(host, SDHCI_SOFTWARE_RESET) & mask) {
+ if (timeout == 0) {
+ pr_err("%s: Reset 0x%x never completed.\n",
+ mmc_hostname(host->mmc), (int)mask);
+ return;
+ }
+ timeout--;
+ mdelay(1);
+ }
+
+ if (100-timeout > 10 && 100-timeout > host->max_delay) {
+ host->max_delay = 100-timeout;
+ pr_warn("Warning: MMC controller hung for %d ms\n",
+ host->max_delay);
+ }
+}
+
+static void bcm2835_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios);
+
+static void bcm2835_mmc_init(struct bcm2835_host *host, int soft)
+{
+ if (soft)
+ bcm2835_mmc_reset(host, SDHCI_RESET_CMD|SDHCI_RESET_DATA);
+ else
+ bcm2835_mmc_reset(host, SDHCI_RESET_ALL);
+
+ host->ier = SDHCI_INT_BUS_POWER | SDHCI_INT_DATA_END_BIT |
+ SDHCI_INT_DATA_CRC | SDHCI_INT_DATA_TIMEOUT |
+ SDHCI_INT_INDEX | SDHCI_INT_END_BIT | SDHCI_INT_CRC |
+ SDHCI_INT_TIMEOUT | SDHCI_INT_DATA_END |
+ SDHCI_INT_RESPONSE;
+
+ bcm2835_mmc_writel(host, host->ier, SDHCI_INT_ENABLE);
+ bcm2835_mmc_writel(host, host->ier, SDHCI_SIGNAL_ENABLE);
+
+ if (soft) {
+ /* force clock reconfiguration */
+ host->clock = 0;
+ bcm2835_mmc_set_ios(host->mmc, &host->mmc->ios);
+ }
+}
+
+
+
+static void bcm2835_mmc_finish_data(struct bcm2835_host *host);
+
+static void bcm2835_mmc_dma_complete(void *param)
+{
+ struct bcm2835_host *host = param;
+ struct dma_chan *dma_chan;
+ unsigned long flags;
+ u32 dir_data;
+
+ spin_lock_irqsave(&host->lock, flags);
+
+ if (host->data && !(host->data->flags & MMC_DATA_WRITE)) {
+ /* otherwise handled in SDHCI IRQ */
+ dma_chan = host->dma_chan_rx;
+ dir_data = DMA_FROM_DEVICE;
+
+ dma_unmap_sg(dma_chan->device->dev,
+ host->data->sg, host->data->sg_len,
+ dir_data);
+
+ bcm2835_mmc_finish_data(host);
+ }
+
+ spin_unlock_irqrestore(&host->lock, flags);
+}
+
+static void bcm2835_bcm2835_mmc_read_block_pio(struct bcm2835_host *host)
+{
+ unsigned long flags;
+ size_t blksize, len, chunk;
+
+ u32 uninitialized_var(scratch);
+ u8 *buf;
+
+ blksize = host->data->blksz;
+ chunk = 0;
+
+ local_irq_save(flags);
+
+ while (blksize) {
+ if (!sg_miter_next(&host->sg_miter))
+ BUG();
+
+ len = min(host->sg_miter.length, blksize);
+
+ blksize -= len;
+ host->sg_miter.consumed = len;
+
+ buf = host->sg_miter.addr;
+
+ while (len) {
+ if (chunk == 0) {
+ scratch = bcm2835_mmc_readl(host, SDHCI_BUFFER);
+ chunk = 4;
+ }
+
+ *buf = scratch & 0xFF;
+
+ buf++;
+ scratch >>= 8;
+ chunk--;
+ len--;
+ }
+ }
+
+ sg_miter_stop(&host->sg_miter);
+
+ local_irq_restore(flags);
+}
+
+static void bcm2835_bcm2835_mmc_write_block_pio(struct bcm2835_host *host)
+{
+ unsigned long flags;
+ size_t blksize, len, chunk;
+ u32 scratch;
+ u8 *buf;
+
+ blksize = host->data->blksz;
+ chunk = 0;
+ chunk = 0;
+ scratch = 0;
+
+ local_irq_save(flags);
+
+ while (blksize) {
+ if (!sg_miter_next(&host->sg_miter))
+ BUG();
+
+ len = min(host->sg_miter.length, blksize);
+
+ blksize -= len;
+ host->sg_miter.consumed = len;
+
+ buf = host->sg_miter.addr;
+
+ while (len) {
+ scratch |= (u32)*buf << (chunk * 8);
+
+ buf++;
+ chunk++;
+ len--;
+
+ if ((chunk == 4) || ((len == 0) && (blksize == 0))) {
+ mmc_raw_writel(host, scratch, SDHCI_BUFFER);
+ chunk = 0;
+ scratch = 0;
+ }
+ }
+ }
+
+ sg_miter_stop(&host->sg_miter);
+
+ local_irq_restore(flags);
+}
+
+
+static void bcm2835_mmc_transfer_pio(struct bcm2835_host *host)
+{
+ u32 mask;
+
+ BUG_ON(!host->data);
+
+ if (host->blocks == 0)
+ return;
+
+ if (host->data->flags & MMC_DATA_READ)
+ mask = SDHCI_DATA_AVAILABLE;
+ else
+ mask = SDHCI_SPACE_AVAILABLE;
+
+ while (bcm2835_mmc_readl(host, SDHCI_PRESENT_STATE) & mask) {
+
+ if (host->data->flags & MMC_DATA_READ)
+ bcm2835_bcm2835_mmc_read_block_pio(host);
+ else
+ bcm2835_bcm2835_mmc_write_block_pio(host);
+
+ host->blocks--;
+
+ /* QUIRK used in sdhci.c removes the 'if' */
+ /* but it seems this is unnecessary */
+ if (host->blocks == 0)
+ break;
+
+
+ }
+}
+
+
+static void bcm2835_mmc_transfer_dma(struct bcm2835_host *host)
+{
+ u32 len, dir_data, dir_slave;
+ struct dma_async_tx_descriptor *desc = NULL;
+ struct dma_chan *dma_chan;
+
+
+ WARN_ON(!host->data);
+
+ if (!host->data)
+ return;
+
+ if (host->blocks == 0)
+ return;
+
+ if (host->data->flags & MMC_DATA_READ) {
+ dma_chan = host->dma_chan_rx;
+ dir_data = DMA_FROM_DEVICE;
+ dir_slave = DMA_DEV_TO_MEM;
+ } else {
+ dma_chan = host->dma_chan_tx;
+ dir_data = DMA_TO_DEVICE;
+ dir_slave = DMA_MEM_TO_DEV;
+ }
+
+ BUG_ON(!dma_chan->device);
+ BUG_ON(!dma_chan->device->dev);
+ BUG_ON(!host->data->sg);
+
+ len = dma_map_sg(dma_chan->device->dev, host->data->sg,
+ host->data->sg_len, dir_data);
+ if (len > 0) {
+ desc = dmaengine_prep_slave_sg(dma_chan, host->data->sg,
+ len, dir_slave,
+ DMA_PREP_INTERRUPT |
+ DMA_CTRL_ACK);
+ } else {
+ dev_err(mmc_dev(host->mmc), "dma_map_sg returned zero length\n");
+ }
+ if (desc) {
+ bcm2835_mmc_unsignal_irqs(host, SDHCI_INT_DATA_AVAIL |
+ SDHCI_INT_SPACE_AVAIL);
+ host->tx_desc = desc;
+ desc->callback = bcm2835_mmc_dma_complete;
+ desc->callback_param = host;
+ dmaengine_submit(desc);
+ dma_async_issue_pending(dma_chan);
+ }
+
+}
+
+
+
+static void bcm2835_mmc_set_transfer_irqs(struct bcm2835_host *host)
+{
+ u32 pio_irqs = SDHCI_INT_DATA_AVAIL | SDHCI_INT_SPACE_AVAIL;
+ u32 dma_irqs = SDHCI_INT_DMA_END | SDHCI_INT_ADMA_ERROR;
+
+ if (host->use_dma)
+ host->ier = (host->ier & ~pio_irqs) | dma_irqs;
+ else
+ host->ier = (host->ier & ~dma_irqs) | pio_irqs;
+
+ bcm2835_mmc_writel(host, host->ier, SDHCI_INT_ENABLE);
+ bcm2835_mmc_writel(host, host->ier, SDHCI_SIGNAL_ENABLE);
+}
+
+
+static void bcm2835_mmc_prepare_data(struct bcm2835_host *host,
+ struct mmc_command *cmd)
+{
+ u8 count;
+ struct mmc_data *data = cmd->data;
+
+ WARN_ON(host->data);
+
+ if (data || (cmd->flags & MMC_RSP_BUSY)) {
+ count = TIMEOUT_VAL;
+ bcm2835_mmc_writeb(host, count, SDHCI_TIMEOUT_CONTROL);
+ }
+
+ if (!data)
+ return;
+
+ /* Sanity checks */
+ BUG_ON(data->blksz * data->blocks > 524288);
+ BUG_ON(data->blksz > host->mmc->max_blk_size);
+ BUG_ON(data->blocks > 65535);
+
+ host->data = data;
+ host->data_early = 0;
+ host->data->bytes_xfered = 0;
+
+
+ if (!(host->flags & SDHCI_REQ_USE_DMA)) {
+ int flags;
+
+ flags = SG_MITER_ATOMIC;
+ if (host->data->flags & MMC_DATA_READ)
+ flags |= SG_MITER_TO_SG;
+ else
+ flags |= SG_MITER_FROM_SG;
+ sg_miter_start(&host->sg_miter, data->sg, data->sg_len, flags);
+ host->blocks = data->blocks;
+ }
+
+ host->use_dma = host->have_dma && data->blocks > PIO_DMA_BARRIER;
+
+ bcm2835_mmc_set_transfer_irqs(host);
+
+ /* Set the DMA boundary value and block size */
+ bcm2835_mmc_writew(host, SDHCI_MAKE_BLKSZ(SDHCI_DEFAULT_BOUNDARY_ARG,
+ data->blksz), SDHCI_BLOCK_SIZE);
+ bcm2835_mmc_writew(host, data->blocks, SDHCI_BLOCK_COUNT);
+
+ BUG_ON(!host->data);
+}
+
+static void bcm2835_mmc_set_transfer_mode(struct bcm2835_host *host,
+ struct mmc_command *cmd)
+{
+ u16 mode;
+ struct mmc_data *data = cmd->data;
+
+ if (data == NULL) {
+ /* clear Auto CMD settings for no data CMDs */
+ mode = bcm2835_mmc_readw(host, SDHCI_TRANSFER_MODE);
+ bcm2835_mmc_writew(host, mode & ~(SDHCI_TRNS_AUTO_CMD12 |
+ SDHCI_TRNS_AUTO_CMD23), SDHCI_TRANSFER_MODE);
+ return;
+ }
+
+ WARN_ON(!host->data);
+
+ mode = SDHCI_TRNS_BLK_CNT_EN;
+
+ if ((mmc_op_multi(cmd->opcode) || data->blocks > 1)) {
+ mode |= SDHCI_TRNS_MULTI;
+
+ /*
+ * If we are sending CMD23, CMD12 never gets sent
+ * on successful completion (so no Auto-CMD12).
+ */
+ if (!host->mrq->sbc && (host->flags & SDHCI_AUTO_CMD12))
+ mode |= SDHCI_TRNS_AUTO_CMD12;
+ else if (host->mrq->sbc && (host->flags & SDHCI_AUTO_CMD23)) {
+ mode |= SDHCI_TRNS_AUTO_CMD23;
+ bcm2835_mmc_writel(host, host->mrq->sbc->arg,
+ SDHCI_ARGUMENT2);
+ }
+ }
+
+ if (data->flags & MMC_DATA_READ)
+ mode |= SDHCI_TRNS_READ;
+ if (host->flags & SDHCI_REQ_USE_DMA)
+ mode |= SDHCI_TRNS_DMA;
+
+ bcm2835_mmc_writew(host, mode, SDHCI_TRANSFER_MODE);
+}
+
+void bcm2835_mmc_send_command(struct bcm2835_host *host,
+ struct mmc_command *cmd)
+{
+ int flags;
+ u32 mask;
+ unsigned long timeout;
+
+ WARN_ON(host->cmd);
+
+ /* Wait max 10 ms */
+ timeout = 1000;
+
+ mask = SDHCI_CMD_INHIBIT;
+ if ((cmd->data != NULL) || (cmd->flags & MMC_RSP_BUSY))
+ mask |= SDHCI_DATA_INHIBIT;
+
+ /* We shouldn't wait for data inihibit for stop commands, even
+ though they might use busy signaling */
+ if (host->mrq->data && (cmd == host->mrq->data->stop))
+ mask &= ~SDHCI_DATA_INHIBIT;
+
+ while (bcm2835_mmc_readl(host, SDHCI_PRESENT_STATE) & mask) {
+ if (timeout == 0) {
+ pr_err("%s: Controller never released inhibit bit(s).\n",
+ mmc_hostname(host->mmc));
+ cmd->error = -EIO;
+ tasklet_schedule(&host->finish_tasklet);
+ return;
+ }
+ timeout--;
+ udelay(10);
+ }
+
+ if ((1000-timeout)/100 > 1 && (1000-timeout)/100 > host->max_delay) {
+ host->max_delay = (1000-timeout)/100;
+ pr_warn("Warning: MMC controller hung for %d ms\n",
+ host->max_delay);
+ }
+
+ timeout = jiffies;
+ if (!cmd->data && cmd->busy_timeout > 9000)
+ timeout += DIV_ROUND_UP(cmd->busy_timeout, 1000) * HZ + HZ;
+ else
+ timeout += 10 * HZ;
+ mod_timer(&host->timer, timeout);
+
+ host->cmd = cmd;
+
+ bcm2835_mmc_prepare_data(host, cmd);
+
+ bcm2835_mmc_writel(host, cmd->arg, SDHCI_ARGUMENT);
+
+ bcm2835_mmc_set_transfer_mode(host, cmd);
+
+ if ((cmd->flags & MMC_RSP_136) && (cmd->flags & MMC_RSP_BUSY)) {
+ pr_err("%s: Unsupported response type!\n",
+ mmc_hostname(host->mmc));
+ cmd->error = -EINVAL;
+ tasklet_schedule(&host->finish_tasklet);
+ return;
+ }
+
+ if (!(cmd->flags & MMC_RSP_PRESENT))
+ flags = SDHCI_CMD_RESP_NONE;
+ else if (cmd->flags & MMC_RSP_136)
+ flags = SDHCI_CMD_RESP_LONG;
+ else if (cmd->flags & MMC_RSP_BUSY)
+ flags = SDHCI_CMD_RESP_SHORT_BUSY;
+ else
+ flags = SDHCI_CMD_RESP_SHORT;
+
+ if (cmd->flags & MMC_RSP_CRC)
+ flags |= SDHCI_CMD_CRC;
+ if (cmd->flags & MMC_RSP_OPCODE)
+ flags |= SDHCI_CMD_INDEX;
+
+ if (cmd->data)
+ flags |= SDHCI_CMD_DATA;
+
+ bcm2835_mmc_writew(host, SDHCI_MAKE_CMD(cmd->opcode, flags),
+ SDHCI_COMMAND);
+}
+
+
+static void bcm2835_mmc_finish_data(struct bcm2835_host *host)
+{
+ struct mmc_data *data;
+
+ BUG_ON(!host->data);
+
+ data = host->data;
+ host->data = NULL;
+
+ if (data->error)
+ data->bytes_xfered = 0;
+ else
+ data->bytes_xfered = data->blksz * data->blocks;
+
+ /*
+ * Need to send CMD12 if -
+ * a) open-ended multiblock transfer (no CMD23)
+ * b) error in multiblock transfer
+ */
+ if (data->stop &&
+ (data->error ||
+ !host->mrq->sbc)) {
+
+ /*
+ * The controller needs a reset of internal state machines
+ * upon error conditions.
+ */
+ if (data->error) {
+ bcm2835_mmc_reset(host, SDHCI_RESET_CMD);
+ bcm2835_mmc_reset(host, SDHCI_RESET_DATA);
+ }
+
+ bcm2835_mmc_send_command(host, data->stop);
+ } else
+ tasklet_schedule(&host->finish_tasklet);
+}
+
+static void bcm2835_mmc_finish_command(struct bcm2835_host *host)
+{
+ int i;
+
+ BUG_ON(host->cmd == NULL);
+
+ if (host->cmd->flags & MMC_RSP_PRESENT) {
+ if (host->cmd->flags & MMC_RSP_136) {
+ /* CRC is stripped so we need to do some shifting. */
+ for (i = 0; i < 4; i++) {
+ host->cmd->resp[i] = bcm2835_mmc_readl(host,
+ SDHCI_RESPONSE + (3-i)*4) << 8;
+ if (i != 3)
+ host->cmd->resp[i] |=
+ bcm2835_mmc_readb(host,
+ SDHCI_RESPONSE + (3-i)*4-1);
+ }
+ } else {
+ host->cmd->resp[0] = bcm2835_mmc_readl(host,
+ SDHCI_RESPONSE);
+ }
+ }
+
+ host->cmd->error = 0;
+
+ /* Finished CMD23, now send actual command. */
+ if (host->cmd == host->mrq->sbc) {
+ host->cmd = NULL;
+ bcm2835_mmc_send_command(host, host->mrq->cmd);
+ } else {
+
+ /* Processed actual command. */
+ if (host->data && host->data_early)
+ bcm2835_mmc_finish_data(host);
+
+ if (!host->cmd->data)
+ tasklet_schedule(&host->finish_tasklet);
+
+ host->cmd = NULL;
+ }
+}
+
+
+static void bcm2835_mmc_timeout_timer(unsigned long data)
+{
+ struct bcm2835_host *host;
+ unsigned long flags;
+
+ host = (struct bcm2835_host *)data;
+
+ spin_lock_irqsave(&host->lock, flags);
+
+ if (host->mrq) {
+ pr_err("%s: Timeout waiting for hardware interrupt.\n",
+ mmc_hostname(host->mmc));
+
+ if (host->data) {
+ host->data->error = -ETIMEDOUT;
+ bcm2835_mmc_finish_data(host);
+ } else {
+ if (host->cmd)
+ host->cmd->error = -ETIMEDOUT;
+ else
+ host->mrq->cmd->error = -ETIMEDOUT;
+
+ tasklet_schedule(&host->finish_tasklet);
+ }
+ }
+
+ mmiowb();
+ spin_unlock_irqrestore(&host->lock, flags);
+}
+
+
+static void bcm2835_mmc_enable_sdio_irq_nolock(struct bcm2835_host *host,
+ int enable)
+{
+ if (!(host->flags & SDHCI_DEVICE_DEAD)) {
+ if (enable)
+ host->ier |= SDHCI_INT_CARD_INT;
+ else
+ host->ier &= ~SDHCI_INT_CARD_INT;
+
+ bcm2835_mmc_writel(host, host->ier, SDHCI_INT_ENABLE);
+ bcm2835_mmc_writel(host, host->ier, SDHCI_SIGNAL_ENABLE);
+ mmiowb();
+ }
+}
+
+static void bcm2835_mmc_enable_sdio_irq(struct mmc_host *mmc, int enable)
+{
+ struct bcm2835_host *host = mmc_priv(mmc);
+ unsigned long flags;
+
+ spin_lock_irqsave(&host->lock, flags);
+ if (enable)
+ host->flags |= SDHCI_SDIO_IRQ_ENABLED;
+ else
+ host->flags &= ~SDHCI_SDIO_IRQ_ENABLED;
+
+ bcm2835_mmc_enable_sdio_irq_nolock(host, enable);
+ spin_unlock_irqrestore(&host->lock, flags);
+}
+
+static void bcm2835_mmc_cmd_irq(struct bcm2835_host *host, u32 intmask)
+{
+
+ BUG_ON(intmask == 0);
+
+ if (!host->cmd) {
+ pr_err("%s: Got command interrupt 0x%08x even though no command operation was in progress.\n",
+ mmc_hostname(host->mmc), (unsigned)intmask);
+ return;
+ }
+
+ if (intmask & SDHCI_INT_TIMEOUT)
+ host->cmd->error = -ETIMEDOUT;
+ else if (intmask & (SDHCI_INT_CRC | SDHCI_INT_END_BIT |
+ SDHCI_INT_INDEX)) {
+ host->cmd->error = -EILSEQ;
+ }
+
+ if (host->cmd->error) {
+ tasklet_schedule(&host->finish_tasklet);
+ return;
+ }
+
+ if (intmask & SDHCI_INT_RESPONSE)
+ bcm2835_mmc_finish_command(host);
+
+}
+
+static void bcm2835_mmc_data_irq(struct bcm2835_host *host, u32 intmask)
+{
+ struct dma_chan *dma_chan;
+ u32 dir_data;
+
+ BUG_ON(intmask == 0);
+
+ if (!host->data) {
+ /*
+ * The "data complete" interrupt is also used to
+ * indicate that a busy state has ended. See comment
+ * above in sdhci_cmd_irq().
+ */
+ if (host->cmd && (host->cmd->flags & MMC_RSP_BUSY)) {
+ if (intmask & SDHCI_INT_DATA_END) {
+ bcm2835_mmc_finish_command(host);
+ return;
+ }
+ }
+
+ pr_debug("%s: Got data interrupt 0x%08x even though no data operation was in progress.\n",
+ mmc_hostname(host->mmc), (unsigned)intmask);
+
+ return;
+ }
+
+ if (intmask & SDHCI_INT_DATA_TIMEOUT)
+ host->data->error = -ETIMEDOUT;
+ else if (intmask & SDHCI_INT_DATA_END_BIT)
+ host->data->error = -EILSEQ;
+ else if ((intmask & SDHCI_INT_DATA_CRC) &&
+ SDHCI_GET_CMD(bcm2835_mmc_readw(host, SDHCI_COMMAND))
+ != MMC_BUS_TEST_R)
+ host->data->error = -EILSEQ;
+
+ if (host->use_dma) {
+ if (host->data->flags & MMC_DATA_WRITE) {
+ /* IRQ handled here */
+
+ dma_chan = host->dma_chan_tx;
+ dir_data = DMA_TO_DEVICE;
+ dma_unmap_sg(dma_chan->device->dev,
+ host->data->sg, host->data->sg_len,
+ dir_data);
+
+ bcm2835_mmc_finish_data(host);
+ }
+
+ } else {
+ if (host->data->error)
+ bcm2835_mmc_finish_data(host);
+ else {
+ if (intmask & (SDHCI_INT_DATA_AVAIL |
+ SDHCI_INT_SPACE_AVAIL))
+ bcm2835_mmc_transfer_pio(host);
+
+ if (intmask & SDHCI_INT_DATA_END) {
+ if (host->cmd) {
+ /*
+ * Data managed to finish before the
+ * command completed. Make sure we do
+ * things in the proper order.
+ */
+ host->data_early = 1;
+ } else {
+ bcm2835_mmc_finish_data(host);
+ }
+ }
+ }
+ }
+}
+
+
+static irqreturn_t bcm2835_mmc_irq(int irq, void *dev_id)
+{
+ irqreturn_t result = IRQ_NONE;
+ struct bcm2835_host *host = dev_id;
+ u32 intmask, mask, unexpected = 0;
+ int max_loops = 16;
+
+ spin_lock(&host->lock);
+
+ intmask = bcm2835_mmc_readl(host, SDHCI_INT_STATUS);
+
+ if (!intmask || intmask == 0xffffffff) {
+ result = IRQ_NONE;
+ goto out;
+ }
+
+ do {
+ /* Clear selected interrupts. */
+ mask = intmask & (SDHCI_INT_CMD_MASK | SDHCI_INT_DATA_MASK |
+ SDHCI_INT_BUS_POWER);
+ bcm2835_mmc_writel(host, mask, SDHCI_INT_STATUS);
+
+
+ if (intmask & SDHCI_INT_CMD_MASK)
+ bcm2835_mmc_cmd_irq(host, intmask & SDHCI_INT_CMD_MASK);
+
+ if (intmask & SDHCI_INT_DATA_MASK)
+ bcm2835_mmc_data_irq(host,
+ intmask & SDHCI_INT_DATA_MASK);
+
+ if (intmask & SDHCI_INT_BUS_POWER)
+ pr_err("%s: Card is consuming too much power!\n",
+ mmc_hostname(host->mmc));
+
+ if (intmask & SDHCI_INT_CARD_INT) {
+ bcm2835_mmc_enable_sdio_irq_nolock(host, false);
+ host->thread_isr |= SDHCI_INT_CARD_INT;
+ result = IRQ_WAKE_THREAD;
+ }
+
+ intmask &= ~(SDHCI_INT_CARD_INSERT | SDHCI_INT_CARD_REMOVE |
+ SDHCI_INT_CMD_MASK | SDHCI_INT_DATA_MASK |
+ SDHCI_INT_ERROR | SDHCI_INT_BUS_POWER |
+ SDHCI_INT_CARD_INT);
+
+ if (intmask) {
+ unexpected |= intmask;
+ bcm2835_mmc_writel(host, intmask, SDHCI_INT_STATUS);
+ }
+
+ if (result == IRQ_NONE)
+ result = IRQ_HANDLED;
+
+ intmask = bcm2835_mmc_readl(host, SDHCI_INT_STATUS);
+ } while (intmask && --max_loops);
+out:
+ spin_unlock(&host->lock);
+
+ if (unexpected) {
+ pr_err("%s: Unexpected interrupt 0x%08x.\n",
+ mmc_hostname(host->mmc), unexpected);
+ }
+
+ return result;
+}
+
+static irqreturn_t bcm2835_mmc_thread_irq(int irq, void *dev_id)
+{
+ struct bcm2835_host *host = dev_id;
+ unsigned long flags;
+ u32 isr;
+
+ spin_lock_irqsave(&host->lock, flags);
+ isr = host->thread_isr;
+ host->thread_isr = 0;
+ spin_unlock_irqrestore(&host->lock, flags);
+
+ if (isr & SDHCI_INT_CARD_INT) {
+ sdio_run_irqs(host->mmc);
+
+ spin_lock_irqsave(&host->lock, flags);
+ if (host->flags & SDHCI_SDIO_IRQ_ENABLED)
+ bcm2835_mmc_enable_sdio_irq_nolock(host, true);
+ spin_unlock_irqrestore(&host->lock, flags);
+ }
+
+ return isr ? IRQ_HANDLED : IRQ_NONE;
+}
+
+
+
+void bcm2835_mmc_set_clock(struct bcm2835_host *host, unsigned int clock)
+{
+ int div = 0; /* Initialized for compiler warning */
+ int real_div = div, clk_mul = 1;
+ u16 clk = 0;
+ unsigned long timeout;
+
+
+ host->mmc->actual_clock = 0;
+
+ bcm2835_mmc_writew(host, 0, SDHCI_CLOCK_CONTROL);
+
+ if (clock == 0)
+ return;
+
+ /* Version 3.00 divisors must be a multiple of 2. */
+ if (host->max_clk <= clock)
+ div = 1;
+ else {
+ for (div = 2; div < SDHCI_MAX_DIV_SPEC_300;
+ div += 2) {
+ if ((host->max_clk / div) <= clock)
+ break;
+ }
+ }
+
+ real_div = div;
+ div >>= 1;
+
+ if (real_div)
+ host->mmc->actual_clock = (host->max_clk * clk_mul) / real_div;
+
+ clk |= (div & SDHCI_DIV_MASK) << SDHCI_DIVIDER_SHIFT;
+ clk |= ((div & SDHCI_DIV_HI_MASK) >> SDHCI_DIV_MASK_LEN)
+ << SDHCI_DIVIDER_HI_SHIFT;
+ clk |= SDHCI_CLOCK_INT_EN;
+ bcm2835_mmc_writew(host, clk, SDHCI_CLOCK_CONTROL);
+
+ /* Wait max 20 ms */
+ timeout = 20;
+ while (!((clk = bcm2835_mmc_readw(host, SDHCI_CLOCK_CONTROL))
+ & SDHCI_CLOCK_INT_STABLE)) {
+ if (timeout == 0) {
+ pr_err("%s: Internal clock never stabilised.\n",
+ mmc_hostname(host->mmc));
+ return;
+ }
+ timeout--;
+ mdelay(1);
+ }
+
+ if (20-timeout > 10 && 20-timeout > host->max_delay) {
+ host->max_delay = 20-timeout;
+ pr_warn("Warning: MMC controller hung for %d ms\n",
+ host->max_delay);
+ }
+
+ clk |= SDHCI_CLOCK_CARD_EN;
+ bcm2835_mmc_writew(host, clk, SDHCI_CLOCK_CONTROL);
+}
+
+static void bcm2835_mmc_request(struct mmc_host *mmc, struct mmc_request *mrq)
+{
+ struct bcm2835_host *host;
+ unsigned long flags;
+
+ host = mmc_priv(mmc);
+
+ spin_lock_irqsave(&host->lock, flags);
+
+ WARN_ON(host->mrq != NULL);
+
+ host->mrq = mrq;
+ bcm2835_mmc_send_command(host, mrq->cmd);
+ mmiowb();
+ spin_unlock_irqrestore(&host->lock, flags);
+
+ if (mrq->cmd->data && host->use_dma) {
+ /* DMA transfer starts now, PIO starts after interrupt */
+ bcm2835_mmc_transfer_dma(host);
+ }
+}
+
+
+static void bcm2835_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
+{
+
+ struct bcm2835_host *host = mmc_priv(mmc);
+ unsigned long flags;
+ u8 ctrl;
+ u16 clk, ctrl_2;
+
+
+ spin_lock_irqsave(&host->lock, flags);
+
+ if (!ios->clock || ios->clock != host->clock) {
+ bcm2835_mmc_set_clock(host, ios->clock);
+ host->clock = ios->clock;
+ }
+
+ if (host->pwr != SDHCI_POWER_330) {
+ host->pwr = SDHCI_POWER_330;
+ bcm2835_mmc_writeb(host, SDHCI_POWER_330 | SDHCI_POWER_ON,
+ SDHCI_POWER_CONTROL);
+ }
+
+ ctrl = bcm2835_mmc_readb(host, SDHCI_HOST_CONTROL);
+
+ /* set bus width */
+ ctrl &= ~SDHCI_CTRL_8BITBUS;
+ if (ios->bus_width == MMC_BUS_WIDTH_4)
+ ctrl |= SDHCI_CTRL_4BITBUS;
+ else
+ ctrl &= ~SDHCI_CTRL_4BITBUS;
+
+ ctrl &= ~SDHCI_CTRL_HISPD; /* NO_HISPD_BIT */
+
+
+ bcm2835_mmc_writeb(host, ctrl, SDHCI_HOST_CONTROL);
+ /*
+ * We only need to set Driver Strength if the
+ * preset value enable is not set.
+ */
+ ctrl_2 = bcm2835_mmc_readw(host, SDHCI_HOST_CONTROL2);
+ ctrl_2 &= ~SDHCI_CTRL_DRV_TYPE_MASK;
+ if (ios->drv_type == MMC_SET_DRIVER_TYPE_A)
+ ctrl_2 |= SDHCI_CTRL_DRV_TYPE_A;
+ else if (ios->drv_type == MMC_SET_DRIVER_TYPE_C)
+ ctrl_2 |= SDHCI_CTRL_DRV_TYPE_C;
+
+ bcm2835_mmc_writew(host, ctrl_2, SDHCI_HOST_CONTROL2);
+
+ /* Reset SD Clock Enable */
+ clk = bcm2835_mmc_readw(host, SDHCI_CLOCK_CONTROL);
+ clk &= ~SDHCI_CLOCK_CARD_EN;
+ bcm2835_mmc_writew(host, clk, SDHCI_CLOCK_CONTROL);
+
+ /* Re-enable SD Clock */
+ bcm2835_mmc_set_clock(host, host->clock);
+ bcm2835_mmc_writeb(host, ctrl, SDHCI_HOST_CONTROL);
+
+ mmiowb();
+
+ spin_unlock_irqrestore(&host->lock, flags);
+}
+
+
+static struct mmc_host_ops bcm2835_ops = {
+ .request = bcm2835_mmc_request,
+ .set_ios = bcm2835_mmc_set_ios,
+ .enable_sdio_irq = bcm2835_mmc_enable_sdio_irq,
+};
+
+
+static void bcm2835_mmc_tasklet_finish(unsigned long param)
+{
+ struct bcm2835_host *host;
+ unsigned long flags;
+ struct mmc_request *mrq;
+
+ host = (struct bcm2835_host *)param;
+
+ spin_lock_irqsave(&host->lock, flags);
+
+ /*
+ * If this tasklet gets rescheduled while running, it will
+ * be run again afterwards but without any active request.
+ */
+ if (!host->mrq) {
+ spin_unlock_irqrestore(&host->lock, flags);
+ return;
+ }
+
+ del_timer(&host->timer);
+
+ mrq = host->mrq;
+
+ /*
+ * The controller needs a reset of internal state machines
+ * upon error conditions.
+ */
+ if (!(host->flags & SDHCI_DEVICE_DEAD) &&
+ ((mrq->cmd && mrq->cmd->error) ||
+ (mrq->data && (mrq->data->error ||
+ (mrq->data->stop && mrq->data->stop->error))))) {
+
+ bcm2835_mmc_reset(host, SDHCI_RESET_CMD);
+ bcm2835_mmc_reset(host, SDHCI_RESET_DATA);
+ }
+
+ host->mrq = NULL;
+ host->cmd = NULL;
+ host->data = NULL;
+
+ mmiowb();
+
+ spin_unlock_irqrestore(&host->lock, flags);
+ mmc_request_done(host->mmc, mrq);
+}
+
+
+
+int bcm2835_mmc_add_host(struct bcm2835_host *host)
+{
+ struct mmc_host *mmc;
+#ifndef FORCE_PIO
+ struct dma_slave_config cfg;
+#endif
+ int ret;
+
+ mmc = host->mmc;
+
+ bcm2835_mmc_reset(host, SDHCI_RESET_ALL);
+
+ host->clk_mul = 0;
+
+ mmc->ops = &bcm2835_ops;
+ mmc->f_max = host->max_clk;
+ mmc->f_max = host->max_clk;
+ mmc->f_min = host->max_clk / SDHCI_MAX_DIV_SPEC_300;
+
+ /* SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK */
+ host->timeout_clk = mmc->f_max / 1000;
+ mmc->max_busy_timeout = (1 << 27) / host->timeout_clk;
+
+ /* host controller capabilities */
+ mmc->caps = MMC_CAP_CMD23 | MMC_CAP_ERASE | MMC_CAP_NEEDS_POLL |
+ MMC_CAP_SDIO_IRQ | MMC_CAP_SD_HIGHSPEED |
+ MMC_CAP_MMC_HIGHSPEED | MMC_CAP_4_BIT_DATA;
+
+ host->flags = SDHCI_AUTO_CMD23;
+
+ spin_lock_init(&host->lock);
+
+
+#ifdef FORCE_PIO
+ pr_info("Forcing PIO mode\n");
+ host->have_dma = false;
+#else
+ if (!host->dma_chan_tx || !host->dma_chan_rx ||
+ IS_ERR(host->dma_chan_tx) || IS_ERR(host->dma_chan_rx)) {
+ pr_err("%s: Unable to initialise DMA channels. Falling back to PIO\n",
+ DRIVER_NAME);
+ host->have_dma = false;
+ } else {
+ pr_info("DMA channels allocated for the MMC driver");
+ host->have_dma = true;
+
+ cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
+ cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
+ cfg.slave_id = 11; /* DREQ channel */
+
+ cfg.direction = DMA_MEM_TO_DEV;
+ cfg.src_addr = 0;
+ cfg.dst_addr = host->phys_addr + SDHCI_BUFFER;
+ ret = dmaengine_slave_config(host->dma_chan_tx, &cfg);
+
+ cfg.direction = DMA_DEV_TO_MEM;
+ cfg.src_addr = host->phys_addr + SDHCI_BUFFER;
+ cfg.dst_addr = 0;
+ ret = dmaengine_slave_config(host->dma_chan_rx, &cfg);
+ }
+#endif
+
+
+ mmc->max_segs = 128;
+ mmc->max_req_size = 524288;
+ mmc->max_seg_size = mmc->max_req_size;
+ mmc->max_blk_size = 512;
+ mmc->max_blk_count = 65535;
+
+ /* report supported voltage ranges */
+ mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
+
+ tasklet_init(&host->finish_tasklet,
+ bcm2835_mmc_tasklet_finish, (unsigned long)host);
+
+ setup_timer(&host->timer, bcm2835_mmc_timeout_timer,
+ (unsigned long)host);
+ init_waitqueue_head(&host->buf_ready_int);
+
+ bcm2835_mmc_init(host, 0);
+ ret = request_threaded_irq(host->irq, bcm2835_mmc_irq,
+ bcm2835_mmc_thread_irq, IRQF_SHARED,
+ mmc_hostname(mmc), host);
+
+ if (ret) {
+ pr_err("%s: Failed to request IRQ %d: %d\n",
+ mmc_hostname(mmc), host->irq, ret);
+ goto untasklet;
+ }
+
+ mmiowb();
+ mmc_add_host(mmc);
+
+ pr_info("Load BCM2835 MMC driver\n");
+
+ return 0;
+
+untasklet:
+ tasklet_kill(&host->finish_tasklet);
+
+ return ret;
+}
+
+static int bcm2835_mmc_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct device_node *node = dev->of_node;
+ struct clk *clk;
+ struct resource *iomem;
+ struct bcm2835_host *host = NULL;
+
+ int ret;
+ struct mmc_host *mmc;
+#if !defined(FORCE_PIO)
+ dma_cap_mask_t mask;
+#endif
+
+ iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!iomem) {
+ ret = -ENOMEM;
+ goto err;
+ }
+
+ if (resource_size(iomem) < 0x100)
+ dev_err(&pdev->dev, "Invalid iomem size!\n");
+
+ mmc = mmc_alloc_host(sizeof(struct bcm2835_host), dev);
+ host = mmc_priv(mmc);
+ host->mmc = mmc;
+
+
+ if (IS_ERR(host)) {
+ ret = PTR_ERR(host);
+ goto err;
+ }
+
+ host->phys_addr = iomem->start + BCM2835_VCMMU_SHIFT;
+
+#ifndef FORCE_PIO
+ host->dma_chan_tx = of_dma_request_slave_channel(node, "tx");
+ host->dma_chan_rx = of_dma_request_slave_channel(node, "rx");
+#endif
+ clk = of_clk_get(node, 0);
+ if (IS_ERR(clk)) {
+ dev_err(dev, "get CLOCK failed\n");
+ ret = PTR_ERR(clk);
+ goto out;
+ }
+ host->max_clk = (clk_get_rate(clk));
+ host->irq = platform_get_irq(pdev, 0);
+
+ if (!request_mem_region(iomem->start, resource_size(iomem),
+ mmc_hostname(host->mmc))) {
+ dev_err(&pdev->dev, "cannot request region\n");
+ ret = -EBUSY;
+ goto err_request;
+ }
+
+ host->ioaddr = ioremap(iomem->start, resource_size(iomem));
+ if (!host->ioaddr) {
+ dev_err(&pdev->dev, "failed to remap registers\n");
+ ret = -ENOMEM;
+ goto err_remap;
+ }
+
+ platform_set_drvdata(pdev, host);
+
+
+ if (host->irq <= 0) {
+ dev_err(dev, "get IRQ failed\n");
+ ret = -EINVAL;
+ goto out;
+ }
+
+
+ mmc_of_parse(mmc);
+ host->timeout = msecs_to_jiffies(1000);
+ spin_lock_init(&host->lock);
+ mmc->ops = &bcm2835_ops;
+ return bcm2835_mmc_add_host(host);
+
+
+err_remap:
+ release_mem_region(iomem->start, resource_size(iomem));
+err_request:
+ mmc_free_host(host->mmc);
+err:
+ dev_err(&pdev->dev, "%s failed %d\n", __func__, ret);
+ return ret;
+out:
+ if (mmc)
+ mmc_free_host(mmc);
+ return ret;
+}
+
+static int bcm2835_mmc_remove(struct platform_device *pdev)
+{
+ struct bcm2835_host *host = platform_get_drvdata(pdev);
+ struct resource *iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ unsigned long flags;
+ int dead;
+ u32 scratch;
+
+ dead = 0;
+ scratch = bcm2835_mmc_readl(host, SDHCI_INT_STATUS);
+ if (scratch == (u32)-1)
+ dead = 1;
+
+
+ if (dead) {
+ spin_lock_irqsave(&host->lock, flags);
+
+ host->flags |= SDHCI_DEVICE_DEAD;
+
+ if (host->mrq) {
+ pr_err("%s: Controller removed during transfer!\n",
+ mmc_hostname(host->mmc));
+
+ host->mrq->cmd->error = -ENOMEDIUM;
+ tasklet_schedule(&host->finish_tasklet);
+ }
+
+ spin_unlock_irqrestore(&host->lock, flags);
+ }
+
+ mmc_remove_host(host->mmc);
+
+ if (!dead)
+ bcm2835_mmc_reset(host, SDHCI_RESET_ALL);
+
+ free_irq(host->irq, host);
+
+ del_timer_sync(&host->timer);
+
+ tasklet_kill(&host->finish_tasklet);
+
+ iounmap(host->ioaddr);
+ release_mem_region(iomem->start, resource_size(iomem));
+ mmc_free_host(host->mmc);
+ platform_set_drvdata(pdev, NULL);
+
+ return 0;
+}
+
+
+static const struct of_device_id bcm2835_mmc_match[] = {
+ { .compatible = "brcm,bcm2835-mmc" },
+ { }
+};
+MODULE_DEVICE_TABLE(of, bcm2835_mmc_match);
+
+
+
+static struct platform_driver bcm2835_mmc_driver = {
+ .probe = bcm2835_mmc_probe,
+ .remove = bcm2835_mmc_remove,
+ .driver = {
+ .name = DRIVER_NAME,
+ .owner = THIS_MODULE,
+ .of_match_table = bcm2835_mmc_match,
+ },
+};
+module_platform_driver(bcm2835_mmc_driver);
+
+MODULE_ALIAS("platform:mmc-bcm2835");
+MODULE_DESCRIPTION("BCM2835 SDHCI driver");
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Gellert Weisz");
--
2.1.1
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