From: Alexander Graf Date: Tue, 23 Jan 2018 17:05:22 +0000 (+0100) Subject: mmc: Add bcm2835 sdhost controller X-Git-Tag: v2018.03-rc1~32 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=c8a73a26d6dd9b7d489e66529fe1412425d8f2d1;p=platform%2Fkernel%2Fu-boot.git mmc: Add bcm2835 sdhost controller The BCM2835 family of SoCs has 2 different SD controllers: One based on the SDHCI spec and a custom, home-grown one. This patch implements a driver for the latter based on the Linux driver. This is needed so that we can make use of device trees that assume driver presence of both SD controllers. Signed-off-by: Alexander Graf --- diff --git a/MAINTAINERS b/MAINTAINERS index aa161c8..af9965a 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -97,6 +97,7 @@ S: Orphaned (Since 2017-07) F: arch/arm/mach-bcm283x/ F: drivers/gpio/bcm2835_gpio.c F: drivers/mmc/bcm2835_sdhci.c +F: drivers/mmc/bcm2835_sdhost.c F: drivers/serial/serial_bcm283x_mu.c F: drivers/video/bcm2835.c F: include/dm/platform_data/serial_bcm283x_mu.h diff --git a/drivers/mmc/Kconfig b/drivers/mmc/Kconfig index bc29611..a1b21fd 100644 --- a/drivers/mmc/Kconfig +++ b/drivers/mmc/Kconfig @@ -261,6 +261,20 @@ config MMC_UNIPHIER This selects support for the Matsushita SD/MMC Host Controller on SocioNext UniPhier and Renesas RCar SoCs. +config MMC_BCM2835 + bool "BCM2835 family custom SD/MMC Host Controller support" + depends on ARCH_BCM283X + depends on BLK && DM_MMC + depends on OF_CONTROL + default y + help + This selects support for the custom SD host controller in the BCM2835 + family of devices. + + If you have a BCM2835 platform with SD or MMC devices, say Y here. + + If unsure, say N. + config MMC_SANDBOX bool "Sandbox MMC support" depends on SANDBOX diff --git a/drivers/mmc/Makefile b/drivers/mmc/Makefile index 64b6f21..42113e2 100644 --- a/drivers/mmc/Makefile +++ b/drivers/mmc/Makefile @@ -64,3 +64,4 @@ obj-$(CONFIG_MMC_SDHCI_ZYNQ) += zynq_sdhci.o obj-$(CONFIG_MMC_SUNXI) += sunxi_mmc.o obj-$(CONFIG_MMC_UNIPHIER) += uniphier-sd.o +obj-$(CONFIG_MMC_BCM2835) += bcm2835_sdhost.o diff --git a/drivers/mmc/bcm2835_sdhost.c b/drivers/mmc/bcm2835_sdhost.c new file mode 100644 index 0000000..1bf52a3 --- /dev/null +++ b/drivers/mmc/bcm2835_sdhost.c @@ -0,0 +1,979 @@ +/* + * bcm2835 sdhost driver. + * + * The 2835 has two SD controllers: The Arasan sdhci controller + * (supported by the iproc driver) and a custom sdhost controller + * (supported by this driver). + * + * The sdhci controller supports both sdcard and sdio. The sdhost + * controller supports the sdcard only, but has better performance. + * Also note that the rpi3 has sdio wifi, so driving the sdcard with + * the sdhost controller allows to use the sdhci controller for wifi + * support. + * + * The configuration is done by devicetree via pin muxing. Both + * SD controller are available on the same pins (2 pin groups = pin 22 + * to 27 + pin 48 to 53). So it's possible to use both SD controllers + * at the same time with different pin groups. + * + * This code was ported to U-Boot by + * Alexander Graf + * and is based on drivers/mmc/host/bcm2835.c in Linux which is written by + * Phil Elwell + * Copyright (C) 2015-2016 Raspberry Pi (Trading) Ltd. + * which is 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 + * + * SPDX-License-Identifier: GPL-2.0 + */ +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +DECLARE_GLOBAL_DATA_PTR; + +#define msleep(a) udelay(a * 1000) + +#define SDCMD 0x00 /* Command to SD card - 16 R/W */ +#define SDARG 0x04 /* Argument to SD card - 32 R/W */ +#define SDTOUT 0x08 /* Start value for timeout counter - 32 R/W */ +#define SDCDIV 0x0c /* Start value for clock divider - 11 R/W */ +#define SDRSP0 0x10 /* SD card response (31:0) - 32 R */ +#define SDRSP1 0x14 /* SD card response (63:32) - 32 R */ +#define SDRSP2 0x18 /* SD card response (95:64) - 32 R */ +#define SDRSP3 0x1c /* SD card response (127:96) - 32 R */ +#define SDHSTS 0x20 /* SD host status - 11 R/W */ +#define SDVDD 0x30 /* SD card power control - 1 R/W */ +#define SDEDM 0x34 /* Emergency Debug Mode - 13 R/W */ +#define SDHCFG 0x38 /* Host configuration - 2 R/W */ +#define SDHBCT 0x3c /* Host byte count (debug) - 32 R/W */ +#define SDDATA 0x40 /* Data to/from SD card - 32 R/W */ +#define SDHBLC 0x50 /* Host block count (SDIO/SDHC) - 9 R/W */ + +#define SDCMD_NEW_FLAG 0x8000 +#define SDCMD_FAIL_FLAG 0x4000 +#define SDCMD_BUSYWAIT 0x800 +#define SDCMD_NO_RESPONSE 0x400 +#define SDCMD_LONG_RESPONSE 0x200 +#define SDCMD_WRITE_CMD 0x80 +#define SDCMD_READ_CMD 0x40 +#define SDCMD_CMD_MASK 0x3f + +#define SDCDIV_MAX_CDIV 0x7ff + +#define SDHSTS_BUSY_IRPT 0x400 +#define SDHSTS_BLOCK_IRPT 0x200 +#define SDHSTS_SDIO_IRPT 0x100 +#define SDHSTS_REW_TIME_OUT 0x80 +#define SDHSTS_CMD_TIME_OUT 0x40 +#define SDHSTS_CRC16_ERROR 0x20 +#define SDHSTS_CRC7_ERROR 0x10 +#define SDHSTS_FIFO_ERROR 0x08 +#define SDHSTS_DATA_FLAG 0x01 + +#define SDHSTS_CLEAR_MASK (SDHSTS_BUSY_IRPT | \ + SDHSTS_BLOCK_IRPT | \ + SDHSTS_SDIO_IRPT | \ + SDHSTS_REW_TIME_OUT | \ + SDHSTS_CMD_TIME_OUT | \ + SDHSTS_CRC16_ERROR | \ + SDHSTS_CRC7_ERROR | \ + SDHSTS_FIFO_ERROR) + +#define SDHSTS_TRANSFER_ERROR_MASK (SDHSTS_CRC7_ERROR | \ + SDHSTS_CRC16_ERROR | \ + SDHSTS_REW_TIME_OUT | \ + SDHSTS_FIFO_ERROR) + +#define SDHSTS_ERROR_MASK (SDHSTS_CMD_TIME_OUT | \ + SDHSTS_TRANSFER_ERROR_MASK) + +#define SDHCFG_BUSY_IRPT_EN BIT(10) +#define SDHCFG_BLOCK_IRPT_EN BIT(8) +#define SDHCFG_SDIO_IRPT_EN BIT(5) +#define SDHCFG_DATA_IRPT_EN BIT(4) +#define SDHCFG_SLOW_CARD BIT(3) +#define SDHCFG_WIDE_EXT_BUS BIT(2) +#define SDHCFG_WIDE_INT_BUS BIT(1) +#define SDHCFG_REL_CMD_LINE BIT(0) + +#define SDVDD_POWER_OFF 0 +#define SDVDD_POWER_ON 1 + +#define SDEDM_FORCE_DATA_MODE BIT(19) +#define SDEDM_CLOCK_PULSE BIT(20) +#define SDEDM_BYPASS BIT(21) + +#define SDEDM_FIFO_FILL_SHIFT 4 +#define SDEDM_FIFO_FILL_MASK 0x1f +static u32 edm_fifo_fill(u32 edm) +{ + return (edm >> SDEDM_FIFO_FILL_SHIFT) & SDEDM_FIFO_FILL_MASK; +} + +#define SDEDM_WRITE_THRESHOLD_SHIFT 9 +#define SDEDM_READ_THRESHOLD_SHIFT 14 +#define SDEDM_THRESHOLD_MASK 0x1f + +#define SDEDM_FSM_MASK 0xf +#define SDEDM_FSM_IDENTMODE 0x0 +#define SDEDM_FSM_DATAMODE 0x1 +#define SDEDM_FSM_READDATA 0x2 +#define SDEDM_FSM_WRITEDATA 0x3 +#define SDEDM_FSM_READWAIT 0x4 +#define SDEDM_FSM_READCRC 0x5 +#define SDEDM_FSM_WRITECRC 0x6 +#define SDEDM_FSM_WRITEWAIT1 0x7 +#define SDEDM_FSM_POWERDOWN 0x8 +#define SDEDM_FSM_POWERUP 0x9 +#define SDEDM_FSM_WRITESTART1 0xa +#define SDEDM_FSM_WRITESTART2 0xb +#define SDEDM_FSM_GENPULSES 0xc +#define SDEDM_FSM_WRITEWAIT2 0xd +#define SDEDM_FSM_STARTPOWDOWN 0xf + +#define SDDATA_FIFO_WORDS 16 + +#define FIFO_READ_THRESHOLD 4 +#define FIFO_WRITE_THRESHOLD 4 +#define SDDATA_FIFO_PIO_BURST 8 + +#define SDHST_TIMEOUT_MAX_USEC 100000 + +struct bcm2835_plat { + struct mmc_config cfg; + struct mmc mmc; +}; + +struct bcm2835_host { + void __iomem *ioaddr; + u32 phys_addr; + + int clock; /* Current clock speed */ + unsigned int max_clk; /* Max possible freq */ + unsigned int blocks; /* remaining PIO blocks */ + int irq; /* Device IRQ */ + + u32 ns_per_fifo_word; + + /* cached registers */ + u32 hcfg; + u32 cdiv; + + struct mmc_cmd *cmd; /* Current command */ + struct mmc_data *data; /* Current data request */ + bool data_complete:1;/* Data finished before cmd */ + bool use_busy:1; /* Wait for busy interrupt */ + bool wait_data_complete:1; /* Wait for data */ + + /* for threaded irq handler */ + bool irq_block; + bool irq_busy; + bool irq_data; + + struct udevice *dev; + struct mmc *mmc; + struct bcm2835_plat *plat; +}; + +static void bcm2835_dumpregs(struct bcm2835_host *host) +{ + dev_dbg(dev, "=========== REGISTER DUMP ===========\n"); + dev_dbg(dev, "SDCMD 0x%08x\n", readl(host->ioaddr + SDCMD)); + dev_dbg(dev, "SDARG 0x%08x\n", readl(host->ioaddr + SDARG)); + dev_dbg(dev, "SDTOUT 0x%08x\n", readl(host->ioaddr + SDTOUT)); + dev_dbg(dev, "SDCDIV 0x%08x\n", readl(host->ioaddr + SDCDIV)); + dev_dbg(dev, "SDRSP0 0x%08x\n", readl(host->ioaddr + SDRSP0)); + dev_dbg(dev, "SDRSP1 0x%08x\n", readl(host->ioaddr + SDRSP1)); + dev_dbg(dev, "SDRSP2 0x%08x\n", readl(host->ioaddr + SDRSP2)); + dev_dbg(dev, "SDRSP3 0x%08x\n", readl(host->ioaddr + SDRSP3)); + dev_dbg(dev, "SDHSTS 0x%08x\n", readl(host->ioaddr + SDHSTS)); + dev_dbg(dev, "SDVDD 0x%08x\n", readl(host->ioaddr + SDVDD)); + dev_dbg(dev, "SDEDM 0x%08x\n", readl(host->ioaddr + SDEDM)); + dev_dbg(dev, "SDHCFG 0x%08x\n", readl(host->ioaddr + SDHCFG)); + dev_dbg(dev, "SDHBCT 0x%08x\n", readl(host->ioaddr + SDHBCT)); + dev_dbg(dev, "SDHBLC 0x%08x\n", readl(host->ioaddr + SDHBLC)); + dev_dbg(dev, "===========================================\n"); +} + +static void bcm2835_reset_internal(struct bcm2835_host *host) +{ + u32 temp; + + writel(SDVDD_POWER_OFF, host->ioaddr + SDVDD); + writel(0, host->ioaddr + SDCMD); + writel(0, host->ioaddr + SDARG); + /* Set timeout to a big enough value so we don't hit it */ + writel(0xf00000, host->ioaddr + SDTOUT); + writel(0, host->ioaddr + SDCDIV); + /* Clear status register */ + writel(SDHSTS_CLEAR_MASK, host->ioaddr + SDHSTS); + writel(0, host->ioaddr + SDHCFG); + writel(0, host->ioaddr + SDHBCT); + writel(0, host->ioaddr + SDHBLC); + + /* Limit fifo usage due to silicon bug */ + temp = readl(host->ioaddr + SDEDM); + temp &= ~((SDEDM_THRESHOLD_MASK << SDEDM_READ_THRESHOLD_SHIFT) | + (SDEDM_THRESHOLD_MASK << SDEDM_WRITE_THRESHOLD_SHIFT)); + temp |= (FIFO_READ_THRESHOLD << SDEDM_READ_THRESHOLD_SHIFT) | + (FIFO_WRITE_THRESHOLD << SDEDM_WRITE_THRESHOLD_SHIFT); + writel(temp, host->ioaddr + SDEDM); + /* Wait for FIFO threshold to populate */ + msleep(20); + writel(SDVDD_POWER_ON, host->ioaddr + SDVDD); + /* Wait for all components to go through power on cycle */ + msleep(20); + host->clock = 0; + writel(host->hcfg, host->ioaddr + SDHCFG); + writel(host->cdiv, host->ioaddr + SDCDIV); +} + +static int bcm2835_finish_command(struct bcm2835_host *host); + +static void bcm2835_wait_transfer_complete(struct bcm2835_host *host) +{ + int timediff; + u32 alternate_idle; + + alternate_idle = (host->data->flags & MMC_DATA_READ) ? + SDEDM_FSM_READWAIT : SDEDM_FSM_WRITESTART1; + + timediff = 0; + + while (1) { + u32 edm, fsm; + + edm = readl(host->ioaddr + SDEDM); + fsm = edm & SDEDM_FSM_MASK; + + if ((fsm == SDEDM_FSM_IDENTMODE) || + (fsm == SDEDM_FSM_DATAMODE)) + break; + if (fsm == alternate_idle) { + writel(edm | SDEDM_FORCE_DATA_MODE, + host->ioaddr + SDEDM); + break; + } + + /* Error out after 100000 register reads (~1s) */ + if (timediff++ == 100000) { + dev_err(host->dev, + "wait_transfer_complete - still waiting after %d retries\n", + timediff); + bcm2835_dumpregs(host); + return; + } + } +} + +static int bcm2835_transfer_block_pio(struct bcm2835_host *host, bool is_read) +{ + struct mmc_data *data = host->data; + size_t blksize = data->blocksize; + int copy_words; + u32 hsts = 0; + u32 *buf; + + if (blksize % sizeof(u32)) + return -EINVAL; + + buf = is_read ? (u32 *)data->dest : (u32 *)data->src; + + if (is_read) + data->dest += blksize; + else + data->src += blksize; + + copy_words = blksize / sizeof(u32); + + /* + * Copy all contents from/to the FIFO as far as it reaches, + * then wait for it to fill/empty again and rewind. + */ + while (copy_words) { + int burst_words, words; + u32 edm; + + burst_words = min(SDDATA_FIFO_PIO_BURST, copy_words); + edm = readl(host->ioaddr + SDEDM); + if (is_read) + words = edm_fifo_fill(edm); + else + words = SDDATA_FIFO_WORDS - edm_fifo_fill(edm); + + 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 = readl(host->ioaddr + SDHSTS); + printf("fsm %x, hsts %08x\n", fsm_state, hsts); + if (hsts & SDHSTS_ERROR_MASK) + break; + } + + continue; + } else if (words > copy_words) { + words = copy_words; + } + + copy_words -= words; + + /* Copy current chunk to/from the FIFO */ + while (words) { + if (is_read) + *(buf++) = readl(host->ioaddr + SDDATA); + else + writel(*(buf++), host->ioaddr + SDDATA); + words--; + } + } + + return 0; +} + +static int bcm2835_transfer_pio(struct bcm2835_host *host) +{ + u32 sdhsts; + bool is_read; + int ret = 0; + + is_read = (host->data->flags & MMC_DATA_READ) != 0; + ret = bcm2835_transfer_block_pio(host, is_read); + + if (host->wait_data_complete) + bcm2835_wait_transfer_complete(host); + + sdhsts = readl(host->ioaddr + SDHSTS); + if (sdhsts & (SDHSTS_CRC16_ERROR | + SDHSTS_CRC7_ERROR | + SDHSTS_FIFO_ERROR)) { + printf("%s transfer error - HSTS %08x\n", + is_read ? "read" : "write", sdhsts); + ret = -EILSEQ; + } else if ((sdhsts & (SDHSTS_CMD_TIME_OUT | + SDHSTS_REW_TIME_OUT))) { + printf("%s timeout error - HSTS %08x\n", + is_read ? "read" : "write", sdhsts); + ret = -ETIMEDOUT; + } + + return ret; +} + +static void bcm2835_set_transfer_irqs(struct bcm2835_host *host) +{ + u32 all_irqs = SDHCFG_DATA_IRPT_EN | SDHCFG_BLOCK_IRPT_EN | + SDHCFG_BUSY_IRPT_EN; + + host->hcfg = (host->hcfg & ~all_irqs) | + SDHCFG_DATA_IRPT_EN | + SDHCFG_BUSY_IRPT_EN; + + writel(host->hcfg, host->ioaddr + SDHCFG); +} + +static +void bcm2835_prepare_data(struct bcm2835_host *host, struct mmc_cmd *cmd, + struct mmc_data *data) +{ + WARN_ON(host->data); + + host->data = data; + if (!data) + return; + + host->wait_data_complete = cmd->cmdidx != MMC_CMD_READ_MULTIPLE_BLOCK; + host->data_complete = false; + + /* Use PIO */ + host->blocks = data->blocks; + + bcm2835_set_transfer_irqs(host); + + writel(data->blocksize, host->ioaddr + SDHBCT); + writel(data->blocks, host->ioaddr + SDHBLC); +} + +static u32 bcm2835_read_wait_sdcmd(struct bcm2835_host *host) +{ + u32 value; + int ret; + int timeout_us = SDHST_TIMEOUT_MAX_USEC; + + ret = readl_poll_timeout(host->ioaddr + SDCMD, value, + !(value & SDCMD_NEW_FLAG), timeout_us); + if (ret == -ETIMEDOUT) + printf("%s: timeout (%d us)\n", __func__, timeout_us); + + return value; +} + +static int bcm2835_send_command(struct bcm2835_host *host, struct mmc_cmd *cmd, + struct mmc_data *data) +{ + u32 sdcmd, sdhsts; + + WARN_ON(host->cmd); + + if ((cmd->resp_type & MMC_RSP_136) && (cmd->resp_type & MMC_RSP_BUSY)) { + printf("unsupported response type!\n"); + return -EINVAL; + } + + sdcmd = bcm2835_read_wait_sdcmd(host); + if (sdcmd & SDCMD_NEW_FLAG) { + printf("previous command never completed.\n"); + bcm2835_dumpregs(host); + return -EBUSY; + } + + host->cmd = cmd; + + /* Clear any error flags */ + sdhsts = readl(host->ioaddr + SDHSTS); + if (sdhsts & SDHSTS_ERROR_MASK) + writel(sdhsts, host->ioaddr + SDHSTS); + + bcm2835_prepare_data(host, cmd, data); + + writel(cmd->cmdarg, host->ioaddr + SDARG); + + sdcmd = cmd->cmdidx & SDCMD_CMD_MASK; + + host->use_busy = false; + if (!(cmd->resp_type & MMC_RSP_PRESENT)) { + sdcmd |= SDCMD_NO_RESPONSE; + } else { + if (cmd->resp_type & MMC_RSP_136) + sdcmd |= SDCMD_LONG_RESPONSE; + if (cmd->resp_type & MMC_RSP_BUSY) { + sdcmd |= SDCMD_BUSYWAIT; + host->use_busy = true; + } + } + + if (data) { + if (data->flags & MMC_DATA_WRITE) + sdcmd |= SDCMD_WRITE_CMD; + if (data->flags & MMC_DATA_READ) + sdcmd |= SDCMD_READ_CMD; + } + + writel(sdcmd | SDCMD_NEW_FLAG, host->ioaddr + SDCMD); + + return 0; +} + +static int bcm2835_transfer_complete(struct bcm2835_host *host) +{ + int ret = 0; + + WARN_ON(!host->data_complete); + + host->data = NULL; + + return ret; +} + +static void bcm2835_finish_data(struct bcm2835_host *host) +{ + host->hcfg &= ~(SDHCFG_DATA_IRPT_EN | SDHCFG_BLOCK_IRPT_EN); + writel(host->hcfg, host->ioaddr + SDHCFG); + + host->data_complete = true; + + if (host->cmd) { + /* Data managed to finish before the + * command completed. Make sure we do + * things in the proper order. + */ + dev_dbg(dev, "Finished early - HSTS %08x\n", + readl(host->ioaddr + SDHSTS)); + } else { + bcm2835_transfer_complete(host); + } +} + +static int bcm2835_finish_command(struct bcm2835_host *host) +{ + struct mmc_cmd *cmd = host->cmd; + u32 sdcmd; + int ret = 0; + + sdcmd = bcm2835_read_wait_sdcmd(host); + + /* Check for errors */ + if (sdcmd & SDCMD_NEW_FLAG) { + printf("command never completed.\n"); + bcm2835_dumpregs(host); + return -EIO; + } else if (sdcmd & SDCMD_FAIL_FLAG) { + u32 sdhsts = readl(host->ioaddr + SDHSTS); + + /* Clear the errors */ + writel(SDHSTS_ERROR_MASK, host->ioaddr + SDHSTS); + + if (!(sdhsts & SDHSTS_CRC7_ERROR) || + (host->cmd->cmdidx != MMC_CMD_SEND_OP_COND)) { + if (sdhsts & SDHSTS_CMD_TIME_OUT) { + ret = -ETIMEDOUT; + } else { + printf("unexpected command %d error\n", + host->cmd->cmdidx); + bcm2835_dumpregs(host); + ret = -EILSEQ; + } + + return ret; + } + } + + if (cmd->resp_type & MMC_RSP_PRESENT) { + if (cmd->resp_type & MMC_RSP_136) { + int i; + + for (i = 0; i < 4; i++) { + cmd->response[3 - i] = + readl(host->ioaddr + SDRSP0 + i * 4); + } + } else { + cmd->response[0] = readl(host->ioaddr + SDRSP0); + } + } + + /* Processed actual command. */ + host->cmd = NULL; + if (host->data && host->data_complete) + ret = bcm2835_transfer_complete(host); + + return ret; +} + +static int bcm2835_check_cmd_error(struct bcm2835_host *host, u32 intmask) +{ + int ret = -EINVAL; + + if (!(intmask & SDHSTS_ERROR_MASK)) + return 0; + + if (!host->cmd) + return -EINVAL; + + printf("sdhost_busy_irq: intmask %08x\n", intmask); + if (intmask & SDHSTS_CRC7_ERROR) { + ret = -EILSEQ; + } else if (intmask & (SDHSTS_CRC16_ERROR | + SDHSTS_FIFO_ERROR)) { + ret = -EILSEQ; + } else if (intmask & (SDHSTS_REW_TIME_OUT | SDHSTS_CMD_TIME_OUT)) { + ret = -ETIMEDOUT; + } + bcm2835_dumpregs(host); + return ret; +} + +static int bcm2835_check_data_error(struct bcm2835_host *host, u32 intmask) +{ + int ret = 0; + + if (!host->data) + return 0; + if (intmask & (SDHSTS_CRC16_ERROR | SDHSTS_FIFO_ERROR)) + ret = -EILSEQ; + if (intmask & SDHSTS_REW_TIME_OUT) + ret = -ETIMEDOUT; + + if (ret) + printf("%s:%d %d\n", __func__, __LINE__, ret); + + return ret; +} + +static void bcm2835_busy_irq(struct bcm2835_host *host) +{ + if (WARN_ON(!host->cmd)) { + bcm2835_dumpregs(host); + return; + } + + if (WARN_ON(!host->use_busy)) { + bcm2835_dumpregs(host); + return; + } + host->use_busy = false; + + bcm2835_finish_command(host); +} + +static void bcm2835_data_irq(struct bcm2835_host *host, u32 intmask) +{ + int ret; + + /* + * 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; + + ret = bcm2835_check_data_error(host, intmask); + if (ret) + goto finished; + + 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; + writel(host->hcfg, host->ioaddr + SDHCFG); + bcm2835_transfer_pio(host); + } else { + bcm2835_transfer_pio(host); + host->blocks--; + if ((host->blocks == 0)) + goto finished; + } + return; + +finished: + host->hcfg &= ~(SDHCFG_DATA_IRPT_EN | SDHCFG_BLOCK_IRPT_EN); + writel(host->hcfg, host->ioaddr + SDHCFG); +} + +static void bcm2835_data_threaded_irq(struct bcm2835_host *host) +{ + if (!host->data) + return; + if ((host->blocks == 0)) + bcm2835_finish_data(host); +} + +static void bcm2835_block_irq(struct bcm2835_host *host) +{ + if (WARN_ON(!host->data)) { + bcm2835_dumpregs(host); + return; + } + + WARN_ON(!host->blocks); + if ((--host->blocks == 0)) + bcm2835_finish_data(host); + else + bcm2835_transfer_pio(host); +} + +static irqreturn_t bcm2835_irq(int irq, void *dev_id) +{ + irqreturn_t result = IRQ_NONE; + struct bcm2835_host *host = dev_id; + u32 intmask; + + intmask = readl(host->ioaddr + SDHSTS); + + writel(SDHSTS_BUSY_IRPT | + SDHSTS_BLOCK_IRPT | + SDHSTS_SDIO_IRPT | + SDHSTS_DATA_FLAG, + host->ioaddr + SDHSTS); + + if (intmask & SDHSTS_BLOCK_IRPT) { + bcm2835_check_data_error(host, intmask); + host->irq_block = true; + result = IRQ_WAKE_THREAD; + } + + if (intmask & SDHSTS_BUSY_IRPT) { + if (!bcm2835_check_cmd_error(host, intmask)) { + host->irq_busy = true; + result = IRQ_WAKE_THREAD; + } else { + 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_data_irq(host, intmask); + host->irq_data = true; + result = IRQ_WAKE_THREAD; + } + + return result; +} + +static irqreturn_t bcm2835_threaded_irq(int irq, void *dev_id) +{ + struct bcm2835_host *host = dev_id; + + if (host->irq_block) { + host->irq_block = false; + bcm2835_block_irq(host); + } + + if (host->irq_busy) { + host->irq_busy = false; + bcm2835_busy_irq(host); + } + + if (host->irq_data) { + host->irq_data = false; + bcm2835_data_threaded_irq(host); + } + + return IRQ_HANDLED; +} + +static void bcm2835_irq_poll(struct bcm2835_host *host) +{ + u32 intmask; + + while (1) { + intmask = readl(host->ioaddr + SDHSTS); + if (intmask & (SDHSTS_BUSY_IRPT | SDHSTS_BLOCK_IRPT | + SDHSTS_SDIO_IRPT | SDHSTS_DATA_FLAG)) { + bcm2835_irq(0, host); + bcm2835_threaded_irq(0, host); + return; + } + } +} + +static void bcm2835_set_clock(struct bcm2835_host *host, unsigned int clock) +{ + int div; + + /* The SDCDIV register has 11 bits, and holds (div - 2). But + * in data mode the max is 50MHz 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. + */ + + if (clock < 100000) { + /* Can't stop the clock, but make it as slow as possible + * to show willing + */ + host->cdiv = SDCDIV_MAX_CDIV; + writel(host->cdiv, host->ioaddr + 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->clock = clock; + + /* Calibrate some delays */ + + host->ns_per_fifo_word = (1000000000 / clock) * + ((host->mmc->card_caps & MMC_MODE_4BIT) ? 8 : 32); + + host->cdiv = div; + writel(host->cdiv, host->ioaddr + SDCDIV); + + /* Set the timeout to 500ms */ + writel(host->mmc->clock / 2, host->ioaddr + SDTOUT); +} + +static inline int is_power_of_2(u64 x) +{ + return !(x & (x - 1)); +} + +static int bcm2835_send_cmd(struct udevice *dev, struct mmc_cmd *cmd, + struct mmc_data *data) +{ + struct bcm2835_host *host = dev_get_priv(dev); + u32 edm, fsm; + int ret = 0; + + if (data && !is_power_of_2(data->blocksize)) { + printf("unsupported block size (%d bytes)\n", data->blocksize); + + if (cmd) + return -EINVAL; + } + + edm = readl(host->ioaddr + SDEDM); + fsm = edm & SDEDM_FSM_MASK; + + if ((fsm != SDEDM_FSM_IDENTMODE) && + (fsm != SDEDM_FSM_DATAMODE) && + (cmd && cmd->cmdidx != MMC_CMD_STOP_TRANSMISSION)) { + printf("previous command (%d) not complete (EDM %08x)\n", + readl(host->ioaddr + SDCMD) & SDCMD_CMD_MASK, edm); + bcm2835_dumpregs(host); + + if (cmd) + return -EILSEQ; + + return 0; + } + + if (cmd) { + ret = bcm2835_send_command(host, cmd, data); + if (!ret && !host->use_busy) + ret = bcm2835_finish_command(host); + } + + /* Wait for completion of busy signal or data transfer */ + while (host->use_busy || host->data) + bcm2835_irq_poll(host); + + return ret; +} + +static int bcm2835_set_ios(struct udevice *dev) +{ + struct bcm2835_host *host = dev_get_priv(dev); + struct mmc *mmc = mmc_get_mmc_dev(dev); + + if (!mmc->clock || mmc->clock != host->clock) { + bcm2835_set_clock(host, mmc->clock); + host->clock = mmc->clock; + } + + /* set bus width */ + host->hcfg &= ~SDHCFG_WIDE_EXT_BUS; + if (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; + + writel(host->hcfg, host->ioaddr + SDHCFG); + + return 0; +} + +static void bcm2835_add_host(struct bcm2835_host *host) +{ + struct mmc_config *cfg = &host->plat->cfg; + + cfg->f_max = host->max_clk; + cfg->f_min = host->max_clk / SDCDIV_MAX_CDIV; + cfg->b_max = 65535; + + dev_dbg(dev, "f_max %d, f_min %d\n", + cfg->f_max, cfg->f_min); + + /* host controller capabilities */ + cfg->host_caps = MMC_MODE_4BIT | MMC_MODE_HS | MMC_MODE_HS_52MHz; + + /* report supported voltage ranges */ + cfg->voltages = MMC_VDD_32_33 | MMC_VDD_33_34; + + /* Set interrupt enables */ + host->hcfg = SDHCFG_BUSY_IRPT_EN; + + bcm2835_reset_internal(host); +} + +static int bcm2835_probe(struct udevice *dev) +{ + struct bcm2835_plat *plat = dev_get_platdata(dev); + struct bcm2835_host *host = dev_get_priv(dev); + struct mmc *mmc = mmc_get_mmc_dev(dev); + struct mmc_uclass_priv *upriv = dev_get_uclass_priv(dev); + + host->dev = dev; + host->mmc = mmc; + host->plat = plat; + upriv->mmc = &plat->mmc; + plat->cfg.name = dev->name; + + host->phys_addr = devfdt_get_addr(dev); + if (host->phys_addr == FDT_ADDR_T_NONE) + return -EINVAL; + + host->ioaddr = devm_ioremap(dev, host->phys_addr, SZ_256); + if (!host->ioaddr) + return -ENOMEM; + + host->max_clk = bcm2835_get_mmc_clock(); + + bcm2835_add_host(host); + + dev_dbg(dev, "%s -> OK\n", __func__); + + return 0; +} + +static const struct udevice_id bcm2835_match[] = { + { .compatible = "brcm,bcm2835-sdhost" }, + { } +}; + +static const struct dm_mmc_ops bcm2835_ops = { + .send_cmd = bcm2835_send_cmd, + .set_ios = bcm2835_set_ios, +}; + +static int bcm2835_bind(struct udevice *dev) +{ + struct bcm2835_plat *plat = dev_get_platdata(dev); + + return mmc_bind(dev, &plat->mmc, &plat->cfg); +} + +U_BOOT_DRIVER(bcm2835_sdhost) = { + .name = "bcm2835-sdhost", + .id = UCLASS_MMC, + .of_match = bcm2835_match, + .bind = bcm2835_bind, + .probe = bcm2835_probe, + .priv_auto_alloc_size = sizeof(struct bcm2835_host), + .platdata_auto_alloc_size = sizeof(struct bcm2835_plat), + .ops = &bcm2835_ops, +};