The 2835 has two SD controllers: The Arasan SDHCI controller that we currently use, and a custom SD controller. The custom one runs faster at 16.7MB/sec reads on PIO (according to hdparm -t on a Pi 2B) instead of 10.15MB/sec, and up to 18.45MB/sec with DMA enabled. The code was originally written by Phil Elwell in the downstream Rasbperry Pi tree, and I did a major cleanup on it (+319, -721 lines out of the original 2055) for inclusion. Signed-off-by: Eric Anholt <eric@xxxxxxxxxx> --- drivers/mmc/host/Kconfig | 9 + drivers/mmc/host/Makefile | 1 + drivers/mmc/host/bcm2835-sdhost.c | 1652 +++++++++++++++++++++++++++++++++++++ 3 files changed, 1662 insertions(+) create mode 100644 drivers/mmc/host/bcm2835-sdhost.c diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig index 1526b8a..b991a21 100644 --- a/drivers/mmc/host/Kconfig +++ b/drivers/mmc/host/Kconfig @@ -778,6 +778,15 @@ config MMC_TOSHIBA_PCI depends on PCI help +config MMC_BCM2835_SDHOST + tristate "platform support for the BCM2835 SDHOST MMC Controller" + depends on ARCH_BCM2835 || COMPILE_TEST + help + This selects the BCM2835 SDHOST MMC controller. If you have a BCM2835 + platform with SD or MMC devices, say Y or M here. + + If unsure, say N. + config MMC_MTK tristate "MediaTek SD/MMC Card Interface support" depends on HAS_DMA diff --git a/drivers/mmc/host/Makefile b/drivers/mmc/host/Makefile index 3595f83..b31b994 100644 --- a/drivers/mmc/host/Makefile +++ b/drivers/mmc/host/Makefile @@ -57,6 +57,7 @@ obj-$(CONFIG_MMC_MOXART) += moxart-mmc.o obj-$(CONFIG_MMC_SUNXI) += sunxi-mmc.o obj-$(CONFIG_MMC_USDHI6ROL0) += usdhi6rol0.o obj-$(CONFIG_MMC_TOSHIBA_PCI) += toshsd.o +obj-$(CONFIG_MMC_BCM2835_SDHOST) += bcm2835-sdhost.o obj-$(CONFIG_MMC_REALTEK_PCI) += rtsx_pci_sdmmc.o obj-$(CONFIG_MMC_REALTEK_USB) += rtsx_usb_sdmmc.o diff --git a/drivers/mmc/host/bcm2835-sdhost.c b/drivers/mmc/host/bcm2835-sdhost.c new file mode 100644 index 0000000..a84f675 --- /dev/null +++ b/drivers/mmc/host/bcm2835-sdhost.c @@ -0,0 +1,1652 @@ +/* + * BCM2835 SD host driver. + * + * Author: Phil Elwell <phil@xxxxxxxxxxxxxxx> + * Copyright (C) 2015-2016 Raspberry Pi (Trading) Ltd. + * + * Based on + * mmc-bcm2835.c by Gellert Weisz + * which is, in turn, 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 + * + * 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/>. + */ + +#include <linux/delay.h> +#include <linux/module.h> +#include <linux/io.h> +#include <linux/mmc/mmc.h> +#include <linux/mmc/host.h> +#include <linux/mmc/sd.h> +#include <linux/scatterlist.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> +#include <linux/clk.h> +#include <linux/platform_device.h> +#include <linux/err.h> +#include <linux/blkdev.h> +#include <linux/dmaengine.h> +#include <linux/dma-mapping.h> +#include <linux/of_dma.h> +#include <linux/time.h> +#include <linux/workqueue.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 */ +#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 +/* Reserved */ +/* Reserved */ +#define SDHSTS_DATA_FLAG 0x01 + +#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 SDEDM_FORCE_DATA_MODE BIT(19) +#define SDEDM_CLOCK_PULSE BIT(20) +#define SDEDM_BYPASS BIT(21) + +#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 CMD_DALLY_US 1 + +struct bcm2835_host { + spinlock_t lock; + + void __iomem *ioaddr; + u32 phys_addr; + + struct mmc_host *mmc; + + u32 pio_timeout; /* In jiffies */ + + int clock; /* Current clock speed */ + + unsigned int max_clk; /* Max possible freq */ + + struct tasklet_struct finish_tasklet; /* Tasklet structures */ + + struct work_struct cmd_wait_wq; /* Workqueue function */ + + struct timer_list timer; /* Timer for timeouts */ + + struct sg_mapping_iter sg_miter; /* SG state for PIO */ + unsigned int blocks; /* remaining PIO blocks */ + + int irq; /* Device IRQ */ + + u32 cmd_quick_poll_retries; + u32 ns_per_fifo_word; + + /* cached registers */ + u32 hcfg; + u32 cdiv; + + /* Current request */ + struct mmc_request *mrq; + /* Current command */ + struct mmc_command *cmd; + /* Current data request */ + struct mmc_data *data; + /* Data finished before cmd */ + bool data_complete:1; + /* Drain the fifo when finishing */ + bool flush_fifo:1; + /* Wait for busy interrupt */ + bool use_busy:1; + /* Send CMD23 */ + bool use_sbc:1; + + /*DMA part*/ + struct dma_chan *dma_chan_rx; + struct dma_chan *dma_chan_tx; + /* Channel in use */ + struct dma_chan *dma_chan; + struct dma_async_tx_descriptor *dma_desc; + u32 dma_dir; + u32 drain_words; + struct page *drain_page; + u32 drain_offset; + + bool use_dma; + /*end of DMA part*/ + /* maximum length of time spent waiting */ + int max_delay; + /* Maximum block count for PIO (0 = always DMA) */ + u32 pio_limit; +}; + +static inline void bcm2835_sdhost_write(struct bcm2835_host *host, + u32 val, int reg) +{ + writel(val, host->ioaddr + reg); +} + +static inline u32 bcm2835_sdhost_read(struct bcm2835_host *host, int reg) +{ + return readl(host->ioaddr + reg); +} + +static inline u32 bcm2835_sdhost_read_relaxed(struct bcm2835_host *host, + int reg) +{ + return readl_relaxed(host->ioaddr + reg); +} + +static void bcm2835_sdhost_dumpcmd(struct bcm2835_host *host, + struct mmc_command *cmd, + const char *label) +{ + if (!cmd) + return; + + pr_err("%s:%c%s op %d arg 0x%x flags 0x%x - resp %08x %08x %08x %08x, err %d\n", + mmc_hostname(host->mmc), + (cmd == host->cmd) ? '>' : ' ', + label, cmd->opcode, cmd->arg, cmd->flags, + cmd->resp[0], cmd->resp[1], cmd->resp[2], cmd->resp[3], + cmd->error); +} + +static void bcm2835_sdhost_dumpregs(struct bcm2835_host *host) +{ + if (host->mrq) { + bcm2835_sdhost_dumpcmd(host, host->mrq->sbc, "sbc"); + bcm2835_sdhost_dumpcmd(host, host->mrq->cmd, "cmd"); + if (host->mrq->data) { + pr_err("%s: data blocks %x blksz %x - err %d\n", + mmc_hostname(host->mmc), + host->mrq->data->blocks, + host->mrq->data->blksz, + host->mrq->data->error); + } + bcm2835_sdhost_dumpcmd(host, host->mrq->stop, "stop"); + } + + pr_err("%s: =========== REGISTER DUMP ===========\n", + mmc_hostname(host->mmc)); + + pr_err("%s: SDCMD 0x%08x\n", + mmc_hostname(host->mmc), + bcm2835_sdhost_read(host, SDCMD)); + pr_err("%s: SDARG 0x%08x\n", + mmc_hostname(host->mmc), + bcm2835_sdhost_read(host, SDARG)); + pr_err("%s: SDTOUT 0x%08x\n", + mmc_hostname(host->mmc), + bcm2835_sdhost_read(host, SDTOUT)); + pr_err("%s: SDCDIV 0x%08x\n", + mmc_hostname(host->mmc), + bcm2835_sdhost_read(host, SDCDIV)); + pr_err("%s: SDRSP0 0x%08x\n", + mmc_hostname(host->mmc), + bcm2835_sdhost_read(host, SDRSP0)); + pr_err("%s: SDRSP1 0x%08x\n", + mmc_hostname(host->mmc), + bcm2835_sdhost_read(host, SDRSP1)); + pr_err("%s: SDRSP2 0x%08x\n", + mmc_hostname(host->mmc), + bcm2835_sdhost_read(host, SDRSP2)); + pr_err("%s: SDRSP3 0x%08x\n", + mmc_hostname(host->mmc), + bcm2835_sdhost_read(host, SDRSP3)); + pr_err("%s: SDHSTS 0x%08x\n", + mmc_hostname(host->mmc), + bcm2835_sdhost_read(host, SDHSTS)); + pr_err("%s: SDVDD 0x%08x\n", + mmc_hostname(host->mmc), + bcm2835_sdhost_read(host, SDVDD)); + pr_err("%s: SDEDM 0x%08x\n", + mmc_hostname(host->mmc), + bcm2835_sdhost_read(host, SDEDM)); + pr_err("%s: SDHCFG 0x%08x\n", + mmc_hostname(host->mmc), + bcm2835_sdhost_read(host, SDHCFG)); + pr_err("%s: SDHBCT 0x%08x\n", + mmc_hostname(host->mmc), + bcm2835_sdhost_read(host, SDHBCT)); + pr_err("%s: SDHBLC 0x%08x\n", + mmc_hostname(host->mmc), + bcm2835_sdhost_read(host, SDHBLC)); + + pr_err("%s: ===========================================\n", + mmc_hostname(host->mmc)); +} + +static void bcm2835_sdhost_set_power(struct bcm2835_host *host, bool on) +{ + bcm2835_sdhost_write(host, on ? 1 : 0, SDVDD); +} + +static void bcm2835_sdhost_reset_internal(struct bcm2835_host *host) +{ + u32 temp; + + bcm2835_sdhost_set_power(host, false); + + bcm2835_sdhost_write(host, 0, SDCMD); + bcm2835_sdhost_write(host, 0, SDARG); + bcm2835_sdhost_write(host, 0xf00000, SDTOUT); + bcm2835_sdhost_write(host, 0, SDCDIV); + bcm2835_sdhost_write(host, 0x7f8, SDHSTS); /* Write 1s to clear */ + bcm2835_sdhost_write(host, 0, SDHCFG); + bcm2835_sdhost_write(host, 0, SDHBCT); + bcm2835_sdhost_write(host, 0, SDHBLC); + + /* Limit fifo usage due to silicon bug */ + temp = bcm2835_sdhost_read(host, 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); + bcm2835_sdhost_write(host, temp, SDEDM); + mdelay(10); + bcm2835_sdhost_set_power(host, true); + mdelay(10); + host->clock = 0; + bcm2835_sdhost_write(host, host->hcfg, SDHCFG); + bcm2835_sdhost_write(host, host->cdiv, SDCDIV); +} + +static void bcm2835_sdhost_reset(struct mmc_host *mmc) +{ + struct bcm2835_host *host = mmc_priv(mmc); + unsigned long flags; + + spin_lock_irqsave(&host->lock, flags); + bcm2835_sdhost_reset_internal(host); + spin_unlock_irqrestore(&host->lock, flags); +} + +static void bcm2835_sdhost_set_ios(struct mmc_host *mmc, struct mmc_ios *ios); + +static void bcm2835_sdhost_init(struct bcm2835_host *host, int soft) +{ + pr_debug("bcm2835_sdhost_init(%d)\n", soft); + + /* Set interrupt enables */ + host->hcfg = SDHCFG_BUSY_IRPT_EN; + + bcm2835_sdhost_reset_internal(host); + + if (soft) { + /* force clock reconfiguration */ + host->clock = 0; + bcm2835_sdhost_set_ios(host->mmc, &host->mmc->ios); + } +} + +static void bcm2835_sdhost_wait_transfer_complete(struct bcm2835_host *host) +{ + int timediff; + u32 alternate_idle; + u32 edm; + + alternate_idle = (host->mrq->data->flags & MMC_DATA_READ) ? + SDEDM_FSM_READWAIT : SDEDM_FSM_WRITESTART1; + + edm = bcm2835_sdhost_read(host, SDEDM); + + timediff = 0; + + while (1) { + u32 fsm = edm & SDEDM_FSM_MASK; + + if ((fsm == SDEDM_FSM_IDENTMODE) || + (fsm == SDEDM_FSM_DATAMODE)) + break; + if (fsm == alternate_idle) { + bcm2835_sdhost_write(host, + edm | SDEDM_FORCE_DATA_MODE, + SDEDM); + break; + } + + timediff++; + if (timediff == 100000) { + pr_err("%s: wait_transfer_complete - still waiting after %d retries\n", + mmc_hostname(host->mmc), + timediff); + bcm2835_sdhost_dumpregs(host); + host->mrq->data->error = -ETIMEDOUT; + return; + } + cpu_relax(); + edm = bcm2835_sdhost_read(host, SDEDM); + } +} + +static void bcm2835_sdhost_finish_data(struct bcm2835_host *host); + +static void bcm2835_sdhost_dma_complete(void *param) +{ + struct bcm2835_host *host = param; + struct mmc_data *data = host->data; + unsigned long flags; + + spin_lock_irqsave(&host->lock, flags); + + if (host->dma_chan) { + dma_unmap_sg(host->dma_chan->device->dev, + data->sg, data->sg_len, + host->dma_dir); + + host->dma_chan = NULL; + } + + if (host->drain_words) { + void *page; + u32 *buf; + + page = kmap_atomic(host->drain_page); + buf = page + host->drain_offset; + + while (host->drain_words) { + u32 edm = bcm2835_sdhost_read(host, SDEDM); + + if ((edm >> 4) & 0x1f) + *(buf++) = bcm2835_sdhost_read(host, + SDDATA); + host->drain_words--; + } + + kunmap_atomic(page); + } + + bcm2835_sdhost_finish_data(host); + + spin_unlock_irqrestore(&host->lock, flags); +} + +static void bcm2835_sdhost_transfer_block_pio(struct bcm2835_host *host, + bool is_read) +{ + unsigned long flags; + size_t blksize, len; + u32 *buf; + unsigned long wait_max; + + blksize = host->data->blksz; + + wait_max = jiffies + msecs_to_jiffies(host->pio_timeout); + + local_irq_save(flags); + + while (blksize) { + int copy_words; + u32 hsts = 0; + + if (!sg_miter_next(&host->sg_miter)) { + host->data->error = -EINVAL; + break; + } + + len = min(host->sg_miter.length, blksize); + if (len % 4) { + host->data->error = -EINVAL; + break; + } + + blksize -= len; + host->sg_miter.consumed = len; + + buf = (u32 *)host->sg_miter.addr; + + copy_words = len / 4; + + while (copy_words) { + int burst_words, words; + u32 edm; + + burst_words = SDDATA_FIFO_PIO_BURST; + if (burst_words > copy_words) + burst_words = copy_words; + edm = bcm2835_sdhost_read(host, SDEDM); + if (is_read) + words = ((edm >> 4) & 0x1f); + else + words = SDDATA_FIFO_WORDS - ((edm >> 4) & 0x1f); + + if (words < burst_words) { + int fsm_state = (edm & SDEDM_FSM_MASK); + + if ((is_read && + (fsm_state != SDEDM_FSM_READDATA && + fsm_state != SDEDM_FSM_READWAIT && + fsm_state != SDEDM_FSM_READCRC)) || + (!is_read && + (fsm_state != SDEDM_FSM_WRITEDATA && + fsm_state != SDEDM_FSM_WRITESTART1 && + fsm_state != SDEDM_FSM_WRITESTART2))) { + hsts = bcm2835_sdhost_read(host, + SDHSTS); + pr_err("%s: fsm %x, hsts %x\n", + mmc_hostname(host->mmc), + fsm_state, hsts); + if (hsts & SDHSTS_ERROR_MASK) + break; + } + + if (time_after(jiffies, wait_max)) { + pr_err("%s: PIO %s timeout - EDM %x\n", + is_read ? "read" : "write", + mmc_hostname(host->mmc), + edm); + hsts = SDHSTS_REW_TIME_OUT; + break; + } + ndelay((burst_words - words) * + host->ns_per_fifo_word); + continue; + } else if (words > copy_words) { + words = copy_words; + } + + copy_words -= words; + + while (words) { + if (is_read) { + *(buf++) = bcm2835_sdhost_read(host, + SDDATA); + } else { + bcm2835_sdhost_write(host, *(buf++), + SDDATA); + } + words--; + } + } + + if (hsts & SDHSTS_ERROR_MASK) + break; + } + + sg_miter_stop(&host->sg_miter); + + local_irq_restore(flags); +} + +static void bcm2835_sdhost_transfer_pio(struct bcm2835_host *host) +{ + u32 sdhsts; + bool is_read; + + is_read = (host->data->flags & MMC_DATA_READ) != 0; + bcm2835_sdhost_transfer_block_pio(host, is_read); + + sdhsts = bcm2835_sdhost_read(host, SDHSTS); + if (sdhsts & (SDHSTS_CRC16_ERROR | + SDHSTS_CRC7_ERROR | + SDHSTS_FIFO_ERROR)) { + pr_err("%s: %s transfer error - HSTS %x\n", + mmc_hostname(host->mmc), + is_read ? "read" : "write", + sdhsts); + host->data->error = -EILSEQ; + } else if ((sdhsts & (SDHSTS_CMD_TIME_OUT | + SDHSTS_REW_TIME_OUT))) { + pr_err("%s: %s timeout error - HSTS %x\n", + mmc_hostname(host->mmc), + is_read ? "read" : "write", + sdhsts); + host->data->error = -ETIMEDOUT; + } +} + +static void bcm2835_sdhost_prepare_dma(struct bcm2835_host *host, + struct mmc_data *data) +{ + int len, dir_data, dir_slave; + struct dma_async_tx_descriptor *desc = NULL; + struct dma_chan *dma_chan; + + pr_debug("bcm2835_sdhost_prepare_dma()\n"); + + if (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; + } + + /* The block doesn't manage the FIFO DREQs properly for + * multi-block transfers, so don't attempt to DMA the final + * few words. Unfortunately this requires the final sg entry + * to be trimmed. N.B. This code demands that the overspill + * is contained in a single sg entry. + */ + + host->drain_words = 0; + if ((data->blocks > 1) && (dir_data == DMA_FROM_DEVICE)) { + struct scatterlist *sg; + u32 len; + int i; + + len = min((u32)(FIFO_READ_THRESHOLD - 1) * 4, + (u32)data->blocks * data->blksz); + + for_each_sg(data->sg, sg, data->sg_len, i) { + if (sg_is_last(sg)) { + WARN_ON(sg->length < len); + sg->length -= len; + host->drain_page = (struct page *)sg->page_link; + host->drain_offset = sg->offset + sg->length; + } + } + host->drain_words = len / 4; + } + + len = dma_map_sg(dma_chan->device->dev, data->sg, data->sg_len, + dir_data); + + if (len > 0) { + desc = dmaengine_prep_slave_sg(dma_chan, data->sg, + len, dir_slave, + DMA_PREP_INTERRUPT | + DMA_CTRL_ACK); + } + + if (desc) { + desc->callback = bcm2835_sdhost_dma_complete; + desc->callback_param = host; + host->dma_desc = desc; + host->dma_chan = dma_chan; + host->dma_dir = dir_data; + } +} + +static void bcm2835_sdhost_start_dma(struct bcm2835_host *host) +{ + dmaengine_submit(host->dma_desc); + dma_async_issue_pending(host->dma_chan); +} + +static void bcm2835_sdhost_set_transfer_irqs(struct bcm2835_host *host) +{ + u32 all_irqs = SDHCFG_DATA_IRPT_EN | SDHCFG_BLOCK_IRPT_EN | + SDHCFG_BUSY_IRPT_EN; + + if (host->dma_desc) { + host->hcfg = (host->hcfg & ~all_irqs) | + SDHCFG_BUSY_IRPT_EN; + } else { + host->hcfg = (host->hcfg & ~all_irqs) | + SDHCFG_DATA_IRPT_EN | + SDHCFG_BUSY_IRPT_EN; + } + + bcm2835_sdhost_write(host, host->hcfg, SDHCFG); +} + +static void bcm2835_sdhost_prepare_data(struct bcm2835_host *host, + struct mmc_command *cmd) +{ + struct mmc_data *data = cmd->data; + + WARN_ON(host->data); + + host->data = data; + if (!data) + return; + + /* Sanity checks */ + WARN_ON(data->blksz * data->blocks > 524288); + WARN_ON(data->blksz > host->mmc->max_blk_size); + WARN_ON(data->blocks > 65535); + + host->data_complete = false; + host->flush_fifo = false; + host->data->bytes_xfered = 0; + + if (!host->dma_desc) { + /* Use PIO */ + int flags = SG_MITER_ATOMIC; + + if (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; + } + + bcm2835_sdhost_set_transfer_irqs(host); + + bcm2835_sdhost_write(host, data->blksz, SDHBCT); + bcm2835_sdhost_write(host, data->blocks, SDHBLC); +} + +bool bcm2835_sdhost_send_command(struct bcm2835_host *host, + struct mmc_command *cmd) +{ + u32 sdcmd, sdhsts; + unsigned long timeout; + int delay; + + WARN_ON(host->cmd); + + if (cmd->data) { + pr_debug("%s: send_command %d 0x%x (flags 0x%x) - %s %d*%d\n", + mmc_hostname(host->mmc), + cmd->opcode, cmd->arg, cmd->flags, + (cmd->data->flags & MMC_DATA_READ) ? + "read" : "write", cmd->data->blocks, + cmd->data->blksz); + } else { + pr_debug("%s: send_command %d 0x%x (flags 0x%x)\n", + mmc_hostname(host->mmc), + cmd->opcode, cmd->arg, cmd->flags); + } + + /* Wait max 100 ms */ + timeout = 10000; + + while (bcm2835_sdhost_read(host, SDCMD) & SDCMD_NEW_FLAG) { + if (timeout == 0) { + pr_err("%s: previous command never completed.\n", + mmc_hostname(host->mmc)); + bcm2835_sdhost_dumpregs(host); + cmd->error = -EILSEQ; + tasklet_schedule(&host->finish_tasklet); + return false; + } + timeout--; + udelay(10); + } + + delay = (10000 - timeout) / 100; + if (delay > host->max_delay) { + host->max_delay = delay; + pr_warn("%s: controller hung for %d ms\n", + mmc_hostname(host->mmc), + 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; + + /* Clear any error flags */ + sdhsts = bcm2835_sdhost_read(host, SDHSTS); + if (sdhsts & SDHSTS_ERROR_MASK) + bcm2835_sdhost_write(host, sdhsts, SDHSTS); + + 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 false; + } + + bcm2835_sdhost_prepare_data(host, cmd); + + bcm2835_sdhost_write(host, cmd->arg, SDARG); + + sdcmd = cmd->opcode & SDCMD_CMD_MASK; + + host->use_busy = false; + if (!(cmd->flags & MMC_RSP_PRESENT)) { + sdcmd |= SDCMD_NO_RESPONSE; + } else { + if (cmd->flags & MMC_RSP_136) + sdcmd |= SDCMD_LONG_RESPONSE; + if (cmd->flags & MMC_RSP_BUSY) { + sdcmd |= SDCMD_BUSYWAIT; + host->use_busy = true; + } + } + + if (cmd->data) { + if (cmd->data->flags & MMC_DATA_WRITE) + sdcmd |= SDCMD_WRITE_CMD; + if (cmd->data->flags & MMC_DATA_READ) + sdcmd |= SDCMD_READ_CMD; + } + + bcm2835_sdhost_write(host, sdcmd | SDCMD_NEW_FLAG, SDCMD); + + return true; +} + +static void bcm2835_sdhost_finish_command(struct bcm2835_host *host, + unsigned long *irq_flags); + +static void bcm2835_sdhost_transfer_complete(struct bcm2835_host *host) +{ + struct mmc_data *data; + + WARN_ON(!host->data_complete); + + data = host->data; + host->data = NULL; + + pr_debug("transfer_complete(error %d, stop %d)\n", + data->error, data->stop ? 1 : 0); + + /* Need to send CMD12 if - + * a) open-ended multiblock transfer (no CMD23) + * b) error in multiblock transfer + */ + if (host->mrq->stop && (data->error || !host->use_sbc)) { + if (bcm2835_sdhost_send_command(host, host->mrq->stop)) { + /* No busy, so poll for completion */ + if (!host->use_busy) + bcm2835_sdhost_finish_command(host, NULL); + } + } else { + bcm2835_sdhost_wait_transfer_complete(host); + tasklet_schedule(&host->finish_tasklet); + } +} + +static void bcm2835_sdhost_finish_data(struct bcm2835_host *host) +{ + struct mmc_data *data; + + data = host->data; + + pr_debug("finish_data(error %d, stop %d, sbc %d)\n", + data->error, data->stop ? 1 : 0, + host->mrq->sbc ? 1 : 0); + + host->hcfg &= ~(SDHCFG_DATA_IRPT_EN | SDHCFG_BLOCK_IRPT_EN); + bcm2835_sdhost_write(host, host->hcfg, SDHCFG); + + data->bytes_xfered = data->error ? 0 : (data->blksz * data->blocks); + + host->data_complete = true; + + if (host->cmd) { + /* Data managed to finish before the + * command completed. Make sure we do + * things in the proper order. + */ + pr_debug("Finished early - HSTS %x\n", + bcm2835_sdhost_read(host, SDHSTS)); + } else { + bcm2835_sdhost_transfer_complete(host); + } +} + +/* If irq_flags is valid, the caller is in a thread context and is + * allowed to sleep + */ +static void bcm2835_sdhost_finish_command(struct bcm2835_host *host, + unsigned long *irq_flags) +{ + u32 sdcmd; + u32 retries; + + pr_debug("finish_command(%x)\n", bcm2835_sdhost_read(host, SDCMD)); + + /* Poll quickly at first */ + + retries = host->cmd_quick_poll_retries; + if (!retries) { + /* Work out how many polls take 1us by timing 10us */ + struct timeval start, now; + int us_diff; + + retries = 1; + do { + int i; + + retries *= 2; + + do_gettimeofday(&start); + + for (i = 0; i < retries; i++) { + cpu_relax(); + sdcmd = bcm2835_sdhost_read(host, SDCMD); + } + + do_gettimeofday(&now); + us_diff = (now.tv_sec - start.tv_sec) * 1000000 + + (now.tv_usec - start.tv_usec); + } while (us_diff < 10); + + host->cmd_quick_poll_retries = + ((retries * us_diff + 9) * CMD_DALLY_US) / 10 + 1; + retries = 1; /* We've already waited long enough this time */ + } + + retries = host->cmd_quick_poll_retries; + for (sdcmd = bcm2835_sdhost_read(host, SDCMD); + (sdcmd & SDCMD_NEW_FLAG) && !(sdcmd & SDCMD_FAIL_FLAG) && retries; + retries--) { + cpu_relax(); + sdcmd = bcm2835_sdhost_read(host, SDCMD); + } + + if (!retries) { + unsigned long wait_max; + + if (!irq_flags) { + /* Schedule the work */ + schedule_work(&host->cmd_wait_wq); + return; + } + + /* Wait max 100 ms */ + wait_max = jiffies + msecs_to_jiffies(100); + while (time_before(jiffies, wait_max)) { + spin_unlock_irqrestore(&host->lock, *irq_flags); + usleep_range(1, 10); + spin_lock_irqsave(&host->lock, *irq_flags); + sdcmd = bcm2835_sdhost_read(host, SDCMD); + if (!(sdcmd & SDCMD_NEW_FLAG) || + (sdcmd & SDCMD_FAIL_FLAG)) + break; + } + } + + /* Check for errors */ + if (sdcmd & SDCMD_NEW_FLAG) { + pr_err("%s: command never completed.\n", + mmc_hostname(host->mmc)); + bcm2835_sdhost_dumpregs(host); + host->cmd->error = -EIO; + tasklet_schedule(&host->finish_tasklet); + return; + } else if (sdcmd & SDCMD_FAIL_FLAG) { + u32 sdhsts = bcm2835_sdhost_read(host, SDHSTS); + + /* Clear the errors */ + bcm2835_sdhost_write(host, SDHSTS_ERROR_MASK, SDHSTS); + + if (!(sdhsts & SDHSTS_CRC7_ERROR) || + (host->cmd->opcode != 1)) { + if (sdhsts & SDHSTS_CMD_TIME_OUT) { + host->cmd->error = -ETIMEDOUT; + } else { + pr_err("%s: unexpected command %d error\n", + mmc_hostname(host->mmc), + host->cmd->opcode); + bcm2835_sdhost_dumpregs(host); + host->cmd->error = -EILSEQ; + } + tasklet_schedule(&host->finish_tasklet); + return; + } + } + + if (host->cmd->flags & MMC_RSP_PRESENT) { + if (host->cmd->flags & MMC_RSP_136) { + int i; + + for (i = 0; i < 4; i++) { + host->cmd->resp[3 - i] = + bcm2835_sdhost_read(host, + SDRSP0 + i * 4); + } + + pr_debug("%s: finish_command %08x %08x %08x %08x\n", + mmc_hostname(host->mmc), + host->cmd->resp[0], host->cmd->resp[1], + host->cmd->resp[2], host->cmd->resp[3]); + } else { + host->cmd->resp[0] = bcm2835_sdhost_read(host, SDRSP0); + pr_debug("%s: finish_command %08x\n", + mmc_hostname(host->mmc), + host->cmd->resp[0]); + } + } + + if (host->cmd == host->mrq->sbc) { + /* Finished CMD23, now send actual command. */ + host->cmd = NULL; + if (bcm2835_sdhost_send_command(host, host->mrq->cmd)) { + if (host->data && host->dma_desc) + /* DMA transfer starts now, PIO starts + * after irq + */ + bcm2835_sdhost_start_dma(host); + + if (!host->use_busy) + bcm2835_sdhost_finish_command(host, NULL); + } + } else if (host->cmd == host->mrq->stop) { + /* Finished CMD12 */ + tasklet_schedule(&host->finish_tasklet); + } else { + /* Processed actual command. */ + host->cmd = NULL; + if (!host->data) + tasklet_schedule(&host->finish_tasklet); + else if (host->data_complete) + bcm2835_sdhost_transfer_complete(host); + } +} + +static void bcm2835_sdhost_timeout(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)); + bcm2835_sdhost_dumpregs(host); + + if (host->data) { + host->data->error = -ETIMEDOUT; + bcm2835_sdhost_finish_data(host); + } else { + if (host->cmd) + host->cmd->error = -ETIMEDOUT; + else + host->mrq->cmd->error = -ETIMEDOUT; + + pr_debug("timeout_timer tasklet_schedule\n"); + tasklet_schedule(&host->finish_tasklet); + } + } + + spin_unlock_irqrestore(&host->lock, flags); +} + +static void bcm2835_sdhost_busy_irq(struct bcm2835_host *host, u32 intmask) +{ + if (!host->cmd) { + pr_err("%s: got command busy interrupt 0x%08x even though no command operation was in progress.\n", + mmc_hostname(host->mmc), (unsigned)intmask); + bcm2835_sdhost_dumpregs(host); + return; + } + + if (!host->use_busy) { + pr_err("%s: got command busy interrupt 0x%08x even though not expecting one.\n", + mmc_hostname(host->mmc), (unsigned)intmask); + bcm2835_sdhost_dumpregs(host); + return; + } + host->use_busy = false; + + if (intmask & SDHSTS_ERROR_MASK) { + pr_err("sdhost_busy_irq: intmask %x, data %p\n", + intmask, host->mrq->data); + if (intmask & SDHSTS_CRC7_ERROR) { + host->cmd->error = -EILSEQ; + } else if (intmask & (SDHSTS_CRC16_ERROR | + SDHSTS_FIFO_ERROR)) { + if (host->mrq->data) + host->mrq->data->error = -EILSEQ; + else + host->cmd->error = -EILSEQ; + } else if (intmask & SDHSTS_REW_TIME_OUT) { + if (host->mrq->data) + host->mrq->data->error = -ETIMEDOUT; + else + host->cmd->error = -ETIMEDOUT; + } else if (intmask & SDHSTS_CMD_TIME_OUT) { + host->cmd->error = -ETIMEDOUT; + } + + bcm2835_sdhost_dumpregs(host); + } else { + bcm2835_sdhost_finish_command(host, NULL); + } +} + +static void bcm2835_sdhost_data_irq(struct bcm2835_host *host, u32 intmask) +{ + /* There are no dedicated data/space available interrupt + * status bits, so it is necessary to use the single shared + * data/space available FIFO status bits. It is therefore not + * an error to get here when there is no data transfer in + * progress. + */ + if (!host->data) + return; + + if (intmask & (SDHSTS_CRC16_ERROR | + SDHSTS_FIFO_ERROR | + SDHSTS_REW_TIME_OUT)) { + if (intmask & (SDHSTS_CRC16_ERROR | + SDHSTS_FIFO_ERROR)) + host->data->error = -EILSEQ; + else + host->data->error = -ETIMEDOUT; + } + + if (host->data->error) { + bcm2835_sdhost_finish_data(host); + } else if (host->data->flags & MMC_DATA_WRITE) { + /* Use the block interrupt for writes after the first block */ + host->hcfg &= ~(SDHCFG_DATA_IRPT_EN); + host->hcfg |= SDHCFG_BLOCK_IRPT_EN; + bcm2835_sdhost_write(host, host->hcfg, SDHCFG); + bcm2835_sdhost_transfer_pio(host); + } else { + bcm2835_sdhost_transfer_pio(host); + host->blocks--; + if ((host->blocks == 0) || host->data->error) + bcm2835_sdhost_finish_data(host); + } +} + +static void bcm2835_sdhost_block_irq(struct bcm2835_host *host, u32 intmask) +{ + if (!host->data) { + pr_err("%s: got block interrupt 0x%08x even though no data operation was in progress.\n", + mmc_hostname(host->mmc), (unsigned)intmask); + bcm2835_sdhost_dumpregs(host); + return; + } + + if (intmask & (SDHSTS_CRC16_ERROR | + SDHSTS_FIFO_ERROR | + SDHSTS_REW_TIME_OUT)) { + if (intmask & (SDHSTS_CRC16_ERROR | + SDHSTS_FIFO_ERROR)) + host->data->error = -EILSEQ; + else + host->data->error = -ETIMEDOUT; + } + + if (!host->dma_desc) { + WARN_ON(!host->blocks); + if (host->data->error || (--host->blocks == 0)) + bcm2835_sdhost_finish_data(host); + else + bcm2835_sdhost_transfer_pio(host); + } else if (host->data->flags & MMC_DATA_WRITE) { + bcm2835_sdhost_finish_data(host); + } +} + +static irqreturn_t bcm2835_sdhost_irq(int irq, void *dev_id) +{ + irqreturn_t result = IRQ_NONE; + struct bcm2835_host *host = dev_id; + u32 intmask; + + spin_lock(&host->lock); + + intmask = bcm2835_sdhost_read(host, SDHSTS); + + bcm2835_sdhost_write(host, + SDHSTS_BUSY_IRPT | + SDHSTS_BLOCK_IRPT | + SDHSTS_SDIO_IRPT | + SDHSTS_DATA_FLAG, + SDHSTS); + + if (intmask & SDHSTS_BLOCK_IRPT) { + bcm2835_sdhost_block_irq(host, intmask); + result = IRQ_HANDLED; + } + + if (intmask & SDHSTS_BUSY_IRPT) { + bcm2835_sdhost_busy_irq(host, intmask); + result = IRQ_HANDLED; + } + + /* There is no true data interrupt status bit, so it is + * necessary to qualify the data flag with the interrupt + * enable bit. + */ + if ((intmask & SDHSTS_DATA_FLAG) && + (host->hcfg & SDHCFG_DATA_IRPT_EN)) { + bcm2835_sdhost_data_irq(host, intmask); + result = IRQ_HANDLED; + } + + spin_unlock(&host->lock); + + return result; +} + +void bcm2835_sdhost_set_clock(struct bcm2835_host *host, unsigned int clock) +{ + int div = 0; /* Initialized for compiler warning */ + + /* The SDCDIV register has 11 bits, and holds (div - 2). But + * in data mode the max is 50MHz wihout 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. + */ + + host->mmc->actual_clock = 0; + + if (clock < 100000) { + /* Can't stop the clock, but make it as slow as possible + * to show willing + */ + host->cdiv = SDCDIV_MAX_CDIV; + bcm2835_sdhost_write(host, host->cdiv, SDCDIV); + return; + } + + div = host->max_clk / clock; + if (div < 2) + div = 2; + if ((host->max_clk / div) > clock) + div++; + div -= 2; + + if (div > SDCDIV_MAX_CDIV) + div = SDCDIV_MAX_CDIV; + + clock = host->max_clk / (div + 2); + host->mmc->actual_clock = clock; + + /* Calibrate some delays */ + + host->ns_per_fifo_word = (1000000000 / clock) * + ((host->mmc->caps & MMC_CAP_4_BIT_DATA) ? 8 : 32); + + host->cdiv = div; + bcm2835_sdhost_write(host, host->cdiv, SDCDIV); + + /* Set the timeout to 500ms */ + bcm2835_sdhost_write(host, host->mmc->actual_clock / 2, SDTOUT); +} + +static void bcm2835_sdhost_request(struct mmc_host *mmc, + struct mmc_request *mrq) +{ + struct bcm2835_host *host; + unsigned long flags; + u32 edm, fsm; + + host = mmc_priv(mmc); + + /* Reset the error statuses in case this is a retry */ + if (mrq->sbc) + mrq->sbc->error = 0; + if (mrq->cmd) + mrq->cmd->error = 0; + if (mrq->data) + mrq->data->error = 0; + if (mrq->stop) + mrq->stop->error = 0; + + if (mrq->data && !is_power_of_2(mrq->data->blksz)) { + pr_err("%s: unsupported block size (%d bytes)\n", + mmc_hostname(mmc), mrq->data->blksz); + mrq->cmd->error = -EINVAL; + mmc_request_done(mmc, mrq); + return; + } + + if (host->use_dma && mrq->data && + (mrq->data->blocks > host->pio_limit)) + bcm2835_sdhost_prepare_dma(host, mrq->data); + + spin_lock_irqsave(&host->lock, flags); + + WARN_ON(host->mrq); + host->mrq = mrq; + + edm = bcm2835_sdhost_read(host, SDEDM); + fsm = edm & SDEDM_FSM_MASK; + + if ((fsm != SDEDM_FSM_IDENTMODE) && + (fsm != SDEDM_FSM_DATAMODE)) { + pr_err("%s: previous command (%d) not complete (EDM %x)\n", + mmc_hostname(host->mmc), + bcm2835_sdhost_read(host, SDCMD) & SDCMD_CMD_MASK, + edm); + bcm2835_sdhost_dumpregs(host); + mrq->cmd->error = -EILSEQ; + tasklet_schedule(&host->finish_tasklet); + spin_unlock_irqrestore(&host->lock, flags); + return; + } + + host->use_sbc = !!mrq->sbc && (host->mrq->data->flags & MMC_DATA_READ); + if (host->use_sbc) { + if (bcm2835_sdhost_send_command(host, mrq->sbc)) { + if (!host->use_busy) + bcm2835_sdhost_finish_command(host, &flags); + } + } else if (bcm2835_sdhost_send_command(host, mrq->cmd)) { + if (host->data && host->dma_desc) { + /* DMA transfer starts now, PIO starts after irq */ + bcm2835_sdhost_start_dma(host); + } + + if (!host->use_busy) + bcm2835_sdhost_finish_command(host, &flags); + } + + spin_unlock_irqrestore(&host->lock, flags); +} + +static void bcm2835_sdhost_set_ios(struct mmc_host *mmc, struct mmc_ios *ios) +{ + struct bcm2835_host *host = mmc_priv(mmc); + unsigned long flags; + + spin_lock_irqsave(&host->lock, flags); + + if (!ios->clock || ios->clock != host->clock) { + bcm2835_sdhost_set_clock(host, ios->clock); + host->clock = ios->clock; + } + + /* set bus width */ + host->hcfg &= ~SDHCFG_WIDE_EXT_BUS; + if (ios->bus_width == MMC_BUS_WIDTH_4) + host->hcfg |= SDHCFG_WIDE_EXT_BUS; + + host->hcfg |= SDHCFG_WIDE_INT_BUS; + + /* Disable clever clock switching, to cope with fast core clocks */ + host->hcfg |= SDHCFG_SLOW_CARD; + + bcm2835_sdhost_write(host, host->hcfg, SDHCFG); + + spin_unlock_irqrestore(&host->lock, flags); +} + +static struct mmc_host_ops bcm2835_sdhost_ops = { + .request = bcm2835_sdhost_request, + .set_ios = bcm2835_sdhost_set_ios, + .hw_reset = bcm2835_sdhost_reset, +}; + +static void bcm2835_sdhost_cmd_wait_work(struct work_struct *work) +{ + struct bcm2835_host *host; + unsigned long flags; + + host = container_of(work, struct bcm2835_host, cmd_wait_wq); + + 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; + } + + bcm2835_sdhost_finish_command(host, &flags); + + spin_unlock_irqrestore(&host->lock, flags); +} + +static void bcm2835_sdhost_tasklet_finish(unsigned long param) +{ + struct bcm2835_host *host; + unsigned long flags; + struct mmc_request *mrq; + struct dma_chan *terminate_chan = NULL; + + 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; + + host->mrq = NULL; + host->cmd = NULL; + host->data = NULL; + + host->dma_desc = NULL; + terminate_chan = host->dma_chan; + host->dma_chan = NULL; + + spin_unlock_irqrestore(&host->lock, flags); + + if (terminate_chan) { + int err = dmaengine_terminate_all(terminate_chan); + + if (err) + pr_err("%s: failed to terminate DMA (%d)\n", + mmc_hostname(host->mmc), err); + } + + mmc_request_done(host->mmc, mrq); +} + +int bcm2835_sdhost_add_host(struct bcm2835_host *host) +{ + struct mmc_host *mmc; + struct dma_slave_config cfg; + char pio_limit_string[20]; + int ret; + + mmc = host->mmc; + + bcm2835_sdhost_reset_internal(host); + + mmc->f_max = host->max_clk; + mmc->f_min = host->max_clk / SDCDIV_MAX_CDIV; + + mmc->max_busy_timeout = ~0 / (mmc->f_max / 1000); + + pr_debug("f_max %d, f_min %d, max_busy_timeout %d\n", + mmc->f_max, mmc->f_min, mmc->max_busy_timeout); + + /* host controller capabilities */ + mmc->caps |= + MMC_CAP_SD_HIGHSPEED | MMC_CAP_MMC_HIGHSPEED | + MMC_CAP_NEEDS_POLL | MMC_CAP_HW_RESET | MMC_CAP_ERASE | + MMC_CAP_CMD23; + + spin_lock_init(&host->lock); + + if (IS_ERR_OR_NULL(host->dma_chan_tx) || + IS_ERR_OR_NULL(host->dma_chan_rx)) { + pr_err("%s: unable to initialise DMA channels. Falling back to PIO\n", + mmc_hostname(mmc)); + host->use_dma = false; + } else { + host->use_dma = true; + + cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; + cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; + cfg.slave_id = 13; /* DREQ channel */ + + cfg.direction = DMA_MEM_TO_DEV; + cfg.src_addr = 0; + cfg.dst_addr = host->phys_addr + SDDATA; + ret = dmaengine_slave_config(host->dma_chan_tx, &cfg); + if (ret) + host->use_dma = false; + + cfg.direction = DMA_DEV_TO_MEM; + cfg.src_addr = host->phys_addr + SDDATA; + cfg.dst_addr = 0; + ret = dmaengine_slave_config(host->dma_chan_rx, &cfg); + if (ret) + host->use_dma = false; + } + + 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_sdhost_tasklet_finish, (unsigned long)host); + + INIT_WORK(&host->cmd_wait_wq, bcm2835_sdhost_cmd_wait_work); + + setup_timer(&host->timer, bcm2835_sdhost_timeout, + (unsigned long)host); + + bcm2835_sdhost_init(host, 0); + + ret = request_irq(host->irq, bcm2835_sdhost_irq, 0 /*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; + } + + mmc_add_host(mmc); + + pio_limit_string[0] = '\0'; + if (host->use_dma && (host->pio_limit > 0)) + sprintf(pio_limit_string, " (>%d)", host->pio_limit); + pr_info("%s: loaded - DMA %s%s\n", + mmc_hostname(mmc), + host->use_dma ? "enabled" : "disabled", + pio_limit_string); + + return 0; + +untasklet: + tasklet_kill(&host->finish_tasklet); + + return ret; +} + +static int bcm2835_sdhost_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct clk *clk; + struct resource *iomem; + struct bcm2835_host *host; + struct mmc_host *mmc; + int ret; + + pr_debug("bcm2835_sdhost_probe\n"); + mmc = mmc_alloc_host(sizeof(*host), dev); + if (!mmc) + return -ENOMEM; + + mmc->ops = &bcm2835_sdhost_ops; + host = mmc_priv(mmc); + host->mmc = mmc; + host->cmd_quick_poll_retries = 0; + host->pio_timeout = msecs_to_jiffies(500); + host->pio_limit = 1; + host->max_delay = 1; /* Warn if over 1ms */ + spin_lock_init(&host->lock); + + iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0); + host->ioaddr = devm_ioremap_resource(dev, iomem); + if (IS_ERR(host->ioaddr)) { + ret = PTR_ERR(host->ioaddr); + goto err; + } + + /* Parse OF address directly to get the physical address for + * DMA to our registers. + */ + host->phys_addr = be32_to_cpup(of_get_address(pdev->dev.of_node, 0, + NULL, NULL)); + + pr_debug(" - ioaddr %lx, iomem->start %lx, phys_addr %lx\n", + (unsigned long)host->ioaddr, + (unsigned long)iomem->start, + (unsigned long)host->phys_addr); + + host->dma_chan = NULL; + host->dma_desc = NULL; + + host->dma_chan_tx = dma_request_slave_channel(dev, "tx"); + host->dma_chan_rx = dma_request_slave_channel(dev, "rx"); + + clk = devm_clk_get(dev, NULL); + if (IS_ERR(clk)) { + ret = PTR_ERR(clk); + if (ret != -EPROBE_DEFER) + dev_err(dev, "could not get clk: %d\n", ret); + goto err; + } + + host->max_clk = clk_get_rate(clk); + + host->irq = platform_get_irq(pdev, 0); + if (host->irq <= 0) { + dev_err(dev, "get IRQ failed\n"); + ret = -EINVAL; + goto err; + } + + pr_debug(" - max_clk %lx, irq %d\n", + (unsigned long)host->max_clk, + (int)host->irq); + + mmc_of_parse(mmc); + + ret = bcm2835_sdhost_add_host(host); + if (ret) + goto err; + + platform_set_drvdata(pdev, host); + + pr_debug("bcm2835_sdhost_probe -> OK\n"); + + return 0; + +err: + pr_debug("bcm2835_sdhost_probe -> err %d\n", ret); + mmc_free_host(mmc); + + return ret; +} + +static int bcm2835_sdhost_remove(struct platform_device *pdev) +{ + struct bcm2835_host *host = platform_get_drvdata(pdev); + + pr_debug("bcm2835_sdhost_remove\n"); + + mmc_remove_host(host->mmc); + + bcm2835_sdhost_set_power(host, false); + + free_irq(host->irq, host); + + del_timer_sync(&host->timer); + + tasklet_kill(&host->finish_tasklet); + + mmc_free_host(host->mmc); + platform_set_drvdata(pdev, NULL); + + pr_debug("bcm2835_sdhost_remove - OK\n"); + return 0; +} + +static const struct of_device_id bcm2835_sdhost_match[] = { + { .compatible = "brcm,bcm2835-sdhost" }, + { } +}; +MODULE_DEVICE_TABLE(of, bcm2835_sdhost_match); + +static struct platform_driver bcm2835_sdhost_driver = { + .probe = bcm2835_sdhost_probe, + .remove = bcm2835_sdhost_remove, + .driver = { + .name = "sdhost-bcm2835", + .of_match_table = bcm2835_sdhost_match, + }, +}; +module_platform_driver(bcm2835_sdhost_driver); + +MODULE_ALIAS("platform:sdhost-bcm2835"); +MODULE_DESCRIPTION("BCM2835 SDHost driver"); +MODULE_LICENSE("GPL v2"); +MODULE_AUTHOR("Phil Elwell"); -- 2.7.0 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
