| Author | Tokens | Token Proportion | Commits | Commit Proportion |
|---|---|---|---|---|
| Eric Anholt | 6609 | 96.13% | 1 | 5.26% |
| Stefan Wahren | 93 | 1.35% | 8 | 42.11% |
| Phil Elwell | 61 | 0.89% | 2 | 10.53% |
| Lukas Wunner | 43 | 0.63% | 3 | 15.79% |
| Peter Ujfalusi | 38 | 0.55% | 1 | 5.26% |
| Gustavo A. R. Silva | 16 | 0.23% | 1 | 5.26% |
| Michal Suchanek | 11 | 0.16% | 1 | 5.26% |
| Saiyam Doshi | 3 | 0.04% | 1 | 5.26% |
| Julia Lawall | 1 | 0.01% | 1 | 5.26% |
| Total | 6875 | 19 |
// SPDX-License-Identifier: GPL-2.0 /* * 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. * * Author: Phil Elwell <phil@raspberrypi.org> * 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 */ #include <linux/clk.h> #include <linux/delay.h> #include <linux/device.h> #include <linux/dmaengine.h> #include <linux/dma-mapping.h> #include <linux/err.h> #include <linux/highmem.h> #include <linux/interrupt.h> #include <linux/io.h> #include <linux/iopoll.h> #include <linux/module.h> #include <linux/of_address.h> #include <linux/of_irq.h> #include <linux/platform_device.h> #include <linux/scatterlist.h> #include <linux/time.h> #include <linux/workqueue.h> #include <linux/mmc/host.h> #include <linux/mmc/mmc.h> #include <linux/mmc/sd.h> #define SDCMD 0x00 /* Command to SD card - 16 R/W */ #define SDARG 0x04 /* Argument to SD card - 32 R/W */ #define SDTOUT 0x08 /* Start value for timeout counter - 32 R/W */ #define SDCDIV 0x0c /* Start value for clock divider - 11 R/W */ #define SDRSP0 0x10 /* SD card response (31:0) - 32 R */ #define SDRSP1 0x14 /* SD card response (63:32) - 32 R */ #define SDRSP2 0x18 /* SD card response (95:64) - 32 R */ #define SDRSP3 0x1c /* SD card response (127:96) - 32 R */ #define SDHSTS 0x20 /* SD host status - 11 R/W */ #define SDVDD 0x30 /* SD card power control - 1 R/W */ #define SDEDM 0x34 /* Emergency Debug Mode - 13 R/W */ #define SDHCFG 0x38 /* Host configuration - 2 R/W */ #define SDHBCT 0x3c /* Host byte count (debug) - 32 R/W */ #define SDDATA 0x40 /* Data to/from SD card - 32 R/W */ #define SDHBLC 0x50 /* Host block count (SDIO/SDHC) - 9 R/W */ #define SDCMD_NEW_FLAG 0x8000 #define SDCMD_FAIL_FLAG 0x4000 #define SDCMD_BUSYWAIT 0x800 #define SDCMD_NO_RESPONSE 0x400 #define SDCMD_LONG_RESPONSE 0x200 #define SDCMD_WRITE_CMD 0x80 #define SDCMD_READ_CMD 0x40 #define SDCMD_CMD_MASK 0x3f #define SDCDIV_MAX_CDIV 0x7ff #define SDHSTS_BUSY_IRPT 0x400 #define SDHSTS_BLOCK_IRPT 0x200 #define SDHSTS_SDIO_IRPT 0x100 #define SDHSTS_REW_TIME_OUT 0x80 #define SDHSTS_CMD_TIME_OUT 0x40 #define SDHSTS_CRC16_ERROR 0x20 #define SDHSTS_CRC7_ERROR 0x10 #define SDHSTS_FIFO_ERROR 0x08 /* 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 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_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 PIO_THRESHOLD 1 /* Maximum block count for PIO (0 = always DMA) */ struct bcm2835_host { spinlock_t lock; struct mutex mutex; void __iomem *ioaddr; u32 phys_addr; struct platform_device *pdev; int clock; /* Current clock speed */ unsigned int max_clk; /* Max possible freq */ struct work_struct dma_work; struct delayed_work timeout_work; /* Timer for timeouts */ struct sg_mapping_iter sg_miter; /* SG state for PIO */ unsigned int blocks; /* remaining PIO blocks */ int irq; /* Device IRQ */ u32 ns_per_fifo_word; /* cached registers */ u32 hcfg; u32 cdiv; struct mmc_request *mrq; /* Current request */ struct mmc_command *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 use_sbc:1; /* Send CMD23 */ /* for threaded irq handler */ bool irq_block; bool irq_busy; bool irq_data; /* DMA part */ struct dma_chan *dma_chan_rxtx; struct dma_chan *dma_chan; struct dma_slave_config dma_cfg_rx; struct dma_slave_config dma_cfg_tx; struct dma_async_tx_descriptor *dma_desc; u32 dma_dir; u32 drain_words; struct page *drain_page; u32 drain_offset; bool use_dma; }; static void bcm2835_dumpcmd(struct bcm2835_host *host, struct mmc_command *cmd, const char *label) { struct device *dev = &host->pdev->dev; if (!cmd) return; dev_dbg(dev, "%c%s op %d arg 0x%x flags 0x%x - resp %08x %08x %08x %08x, err %d\n", (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_dumpregs(struct bcm2835_host *host) { struct mmc_request *mrq = host->mrq; struct device *dev = &host->pdev->dev; if (mrq) { bcm2835_dumpcmd(host, mrq->sbc, "sbc"); bcm2835_dumpcmd(host, mrq->cmd, "cmd"); if (mrq->data) { dev_dbg(dev, "data blocks %x blksz %x - err %d\n", mrq->data->blocks, mrq->data->blksz, mrq->data->error); } bcm2835_dumpcmd(host, mrq->stop, "stop"); } 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); writel(0xf00000, host->ioaddr + SDTOUT); writel(0, host->ioaddr + SDCDIV); writel(0x7f8, host->ioaddr + SDHSTS); /* Write 1s to clear */ 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); msleep(20); writel(SDVDD_POWER_ON, host->ioaddr + SDVDD); msleep(20); host->clock = 0; writel(host->hcfg, host->ioaddr + SDHCFG); writel(host->cdiv, host->ioaddr + SDCDIV); } static void bcm2835_reset(struct mmc_host *mmc) { struct bcm2835_host *host = mmc_priv(mmc); if (host->dma_chan) dmaengine_terminate_sync(host->dma_chan); host->dma_chan = NULL; bcm2835_reset_internal(host); } static void 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->mrq->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; } timediff++; if (timediff == 100000) { dev_err(&host->pdev->dev, "wait_transfer_complete - still waiting after %d retries\n", timediff); bcm2835_dumpregs(host); host->mrq->data->error = -ETIMEDOUT; return; } cpu_relax(); } } static void bcm2835_dma_complete(void *param) { struct bcm2835_host *host = param; schedule_work(&host->dma_work); } static void bcm2835_transfer_block_pio(struct bcm2835_host *host, bool is_read) { unsigned long flags; size_t blksize; unsigned long wait_max; blksize = host->data->blksz; wait_max = jiffies + msecs_to_jiffies(500); local_irq_save(flags); while (blksize) { int copy_words; u32 hsts = 0; size_t len; u32 *buf; 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 = min(SDDATA_FIFO_PIO_BURST, copy_words); edm = readl(host->ioaddr + 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); struct device *dev = &host->pdev->dev; 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); dev_err(dev, "fsm %x, hsts %08x\n", fsm_state, hsts); if (hsts & SDHSTS_ERROR_MASK) break; } if (time_after(jiffies, wait_max)) { dev_err(dev, "PIO %s timeout - EDM %08x\n", is_read ? "read" : "write", 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++) = readl(host->ioaddr + SDDATA); else writel(*(buf++), host->ioaddr + SDDATA); words--; } } if (hsts & SDHSTS_ERROR_MASK) break; } sg_miter_stop(&host->sg_miter); local_irq_restore(flags); } static void bcm2835_transfer_pio(struct bcm2835_host *host) { struct device *dev = &host->pdev->dev; u32 sdhsts; bool is_read; is_read = (host->data->flags & MMC_DATA_READ) != 0; bcm2835_transfer_block_pio(host, is_read); sdhsts = readl(host->ioaddr + SDHSTS); if (sdhsts & (SDHSTS_CRC16_ERROR | SDHSTS_CRC7_ERROR | SDHSTS_FIFO_ERROR)) { dev_err(dev, "%s transfer error - HSTS %08x\n", is_read ? "read" : "write", sdhsts); host->data->error = -EILSEQ; } else if ((sdhsts & (SDHSTS_CMD_TIME_OUT | SDHSTS_REW_TIME_OUT))) { dev_err(dev, "%s timeout error - HSTS %08x\n", is_read ? "read" : "write", sdhsts); host->data->error = -ETIMEDOUT; } } static void bcm2835_prepare_dma(struct bcm2835_host *host, struct mmc_data *data) { int sg_len, dir_data, dir_slave; struct dma_async_tx_descriptor *desc = NULL; struct dma_chan *dma_chan; dma_chan = host->dma_chan_rxtx; if (data->flags & MMC_DATA_READ) { dir_data = DMA_FROM_DEVICE; dir_slave = DMA_DEV_TO_MEM; } else { 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 = sg_page(sg); host->drain_offset = sg->offset + sg->length; } } host->drain_words = len / 4; } /* The parameters have already been validated, so this will not fail */ (void)dmaengine_slave_config(dma_chan, (dir_data == DMA_FROM_DEVICE) ? &host->dma_cfg_rx : &host->dma_cfg_tx); sg_len = dma_map_sg(dma_chan->device->dev, data->sg, data->sg_len, dir_data); if (!sg_len) return; desc = dmaengine_prep_slave_sg(dma_chan, data->sg, sg_len, dir_slave, DMA_PREP_INTERRUPT | DMA_CTRL_ACK); if (!desc) { dma_unmap_sg(dma_chan->device->dev, data->sg, sg_len, dir_data); return; } desc->callback = bcm2835_dma_complete; desc->callback_param = host; host->dma_desc = desc; host->dma_chan = dma_chan; host->dma_dir = dir_data; } static void bcm2835_start_dma(struct bcm2835_host *host) { dmaengine_submit(host->dma_desc); dma_async_issue_pending(host->dma_chan); } 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; 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; } writel(host->hcfg, host->ioaddr + SDHCFG); } static void bcm2835_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; host->data_complete = 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_set_transfer_irqs(host); writel(data->blksz, host->ioaddr + SDHBCT); writel(data->blocks, host->ioaddr + SDHBLC); } static u32 bcm2835_read_wait_sdcmd(struct bcm2835_host *host, u32 max_ms) { struct device *dev = &host->pdev->dev; u32 value; int ret; ret = readl_poll_timeout(host->ioaddr + SDCMD, value, !(value & SDCMD_NEW_FLAG), 1, 10); if (ret == -ETIMEDOUT) /* if it takes a while make poll interval bigger */ ret = readl_poll_timeout(host->ioaddr + SDCMD, value, !(value & SDCMD_NEW_FLAG), 10, max_ms * 1000); if (ret == -ETIMEDOUT) dev_err(dev, "%s: timeout (%d ms)\n", __func__, max_ms); return value; } static void bcm2835_finish_request(struct bcm2835_host *host) { struct dma_chan *terminate_chan = NULL; struct mmc_request *mrq; cancel_delayed_work(&host->timeout_work); 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; if (terminate_chan) { int err = dmaengine_terminate_all(terminate_chan); if (err) dev_err(&host->pdev->dev, "failed to terminate DMA (%d)\n", err); } mmc_request_done(mmc_from_priv(host), mrq); } static bool bcm2835_send_command(struct bcm2835_host *host, struct mmc_command *cmd) { struct device *dev = &host->pdev->dev; u32 sdcmd, sdhsts; unsigned long timeout; WARN_ON(host->cmd); sdcmd = bcm2835_read_wait_sdcmd(host, 100); if (sdcmd & SDCMD_NEW_FLAG) { dev_err(dev, "previous command never completed.\n"); bcm2835_dumpregs(host); cmd->error = -EILSEQ; bcm2835_finish_request(host); return false; } if (!cmd->data && cmd->busy_timeout > 9000) timeout = DIV_ROUND_UP(cmd->busy_timeout, 1000) * HZ + HZ; else timeout = 10 * HZ; schedule_delayed_work(&host->timeout_work, timeout); host->cmd = cmd; /* Clear any error flags */ sdhsts = readl(host->ioaddr + SDHSTS); if (sdhsts & SDHSTS_ERROR_MASK) writel(sdhsts, host->ioaddr + SDHSTS); if ((cmd->flags & MMC_RSP_136) && (cmd->flags & MMC_RSP_BUSY)) { dev_err(dev, "unsupported response type!\n"); cmd->error = -EINVAL; bcm2835_finish_request(host); return false; } bcm2835_prepare_data(host, cmd); writel(cmd->arg, host->ioaddr + 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; } writel(sdcmd | SDCMD_NEW_FLAG, host->ioaddr + SDCMD); return true; } static void bcm2835_transfer_complete(struct bcm2835_host *host) { struct mmc_data *data; WARN_ON(!host->data_complete); data = host->data; host->data = NULL; /* 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_send_command(host, host->mrq->stop)) { /* No busy, so poll for completion */ if (!host->use_busy) bcm2835_finish_command(host); } } else { bcm2835_wait_transfer_complete(host); bcm2835_finish_request(host); } } static void bcm2835_finish_data(struct bcm2835_host *host) { struct device *dev = &host->pdev->dev; struct mmc_data *data; data = host->data; host->hcfg &= ~(SDHCFG_DATA_IRPT_EN | SDHCFG_BLOCK_IRPT_EN); writel(host->hcfg, host->ioaddr + 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. */ dev_dbg(dev, "Finished early - HSTS %08x\n", readl(host->ioaddr + SDHSTS)); } else { bcm2835_transfer_complete(host); } } static void bcm2835_finish_command(struct bcm2835_host *host) { struct device *dev = &host->pdev->dev; struct mmc_command *cmd = host->cmd; u32 sdcmd; sdcmd = bcm2835_read_wait_sdcmd(host, 100); /* Check for errors */ if (sdcmd & SDCMD_NEW_FLAG) { dev_err(dev, "command never completed.\n"); bcm2835_dumpregs(host); host->cmd->error = -EIO; bcm2835_finish_request(host); return; } 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->opcode != MMC_SEND_OP_COND)) { u32 edm, fsm; if (sdhsts & SDHSTS_CMD_TIME_OUT) { host->cmd->error = -ETIMEDOUT; } else { dev_err(dev, "unexpected command %d error\n", host->cmd->opcode); bcm2835_dumpregs(host); host->cmd->error = -EILSEQ; } edm = readl(host->ioaddr + SDEDM); fsm = edm & SDEDM_FSM_MASK; if (fsm == SDEDM_FSM_READWAIT || fsm == SDEDM_FSM_WRITESTART1) /* Kick the FSM out of its wait */ writel(edm | SDEDM_FORCE_DATA_MODE, host->ioaddr + SDEDM); bcm2835_finish_request(host); return; } } if (cmd->flags & MMC_RSP_PRESENT) { if (cmd->flags & MMC_RSP_136) { int i; for (i = 0; i < 4; i++) { cmd->resp[3 - i] = readl(host->ioaddr + SDRSP0 + i * 4); } } else { cmd->resp[0] = readl(host->ioaddr + SDRSP0); } } if (cmd == host->mrq->sbc) { /* Finished CMD23, now send actual command. */ host->cmd = NULL; if (bcm2835_send_command(host, host->mrq->cmd)) { if (host->data && host->dma_desc) /* DMA transfer starts now, PIO starts * after irq */ bcm2835_start_dma(host); if (!host->use_busy) bcm2835_finish_command(host); } } else if (cmd == host->mrq->stop) { /* Finished CMD12 */ bcm2835_finish_request(host); } else { /* Processed actual command. */ host->cmd = NULL; if (!host->data) bcm2835_finish_request(host); else if (host->data_complete) bcm2835_transfer_complete(host); } } static void bcm2835_timeout(struct work_struct *work) { struct delayed_work *d = to_delayed_work(work); struct bcm2835_host *host = container_of(d, struct bcm2835_host, timeout_work); struct device *dev = &host->pdev->dev; mutex_lock(&host->mutex); if (host->mrq) { dev_err(dev, "timeout waiting for hardware interrupt.\n"); bcm2835_dumpregs(host); bcm2835_reset(mmc_from_priv(host)); if (host->data) { host->data->error = -ETIMEDOUT; bcm2835_finish_data(host); } else { if (host->cmd) host->cmd->error = -ETIMEDOUT; else host->mrq->cmd->error = -ETIMEDOUT; bcm2835_finish_request(host); } } mutex_unlock(&host->mutex); } static bool bcm2835_check_cmd_error(struct bcm2835_host *host, u32 intmask) { struct device *dev = &host->pdev->dev; if (!(intmask & SDHSTS_ERROR_MASK)) return false; if (!host->cmd) return true; dev_err(dev, "sdhost_busy_irq: intmask %08x\n", intmask); 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_dumpregs(host); return true; } static void bcm2835_check_data_error(struct bcm2835_host *host, u32 intmask) { if (!host->data) return; if (intmask & (SDHSTS_CRC16_ERROR | SDHSTS_FIFO_ERROR)) host->data->error = -EILSEQ; if (intmask & SDHSTS_REW_TIME_OUT) host->data->error = -ETIMEDOUT; } 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) { /* 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; bcm2835_check_data_error(host, intmask); if (host->data->error) 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) || host->data->error) 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) || host->data->error) bcm2835_finish_data(host); } static void bcm2835_block_irq(struct bcm2835_host *host) { if (WARN_ON(!host->data)) { bcm2835_dumpregs(host); return; } if (!host->dma_desc) { WARN_ON(!host->blocks); if (host->data->error || (--host->blocks == 0)) bcm2835_finish_data(host); else bcm2835_transfer_pio(host); } else if (host->data->flags & MMC_DATA_WRITE) { bcm2835_finish_data(host); } } static irqreturn_t bcm2835_irq(int irq, void *dev_id) { irqreturn_t result = IRQ_NONE; struct bcm2835_host *host = dev_id; u32 intmask; spin_lock(&host->lock); 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; } spin_unlock(&host->lock); return result; } static irqreturn_t bcm2835_threaded_irq(int irq, void *dev_id) { struct bcm2835_host *host = dev_id; unsigned long flags; bool block, busy, data; spin_lock_irqsave(&host->lock, flags); block = host->irq_block; busy = host->irq_busy; data = host->irq_data; host->irq_block = false; host->irq_busy = false; host->irq_data = false; spin_unlock_irqrestore(&host->lock, flags); mutex_lock(&host->mutex); if (block) bcm2835_block_irq(host); if (busy) bcm2835_busy_irq(host); if (data) bcm2835_data_threaded_irq(host); mutex_unlock(&host->mutex); return IRQ_HANDLED; } static void bcm2835_dma_complete_work(struct work_struct *work) { struct bcm2835_host *host = container_of(work, struct bcm2835_host, dma_work); struct mmc_data *data; mutex_lock(&host->mutex); data = host->data; 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) { unsigned long flags; void *page; u32 *buf; if (host->drain_offset & PAGE_MASK) { host->drain_page += host->drain_offset >> PAGE_SHIFT; host->drain_offset &= ~PAGE_MASK; } local_irq_save(flags); page = kmap_atomic(host->drain_page); buf = page + host->drain_offset; while (host->drain_words) { u32 edm = readl(host->ioaddr + SDEDM); if ((edm >> 4) & 0x1f) *(buf++) = readl(host->ioaddr + SDDATA); host->drain_words--; } kunmap_atomic(page); local_irq_restore(flags); } bcm2835_finish_data(host); mutex_unlock(&host->mutex); } static void bcm2835_set_clock(struct bcm2835_host *host, unsigned int clock) { struct mmc_host *mmc = mmc_from_priv(host); 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); mmc->actual_clock = clock; /* Calibrate some delays */ host->ns_per_fifo_word = (1000000000 / clock) * ((mmc->caps & MMC_CAP_4_BIT_DATA) ? 8 : 32); host->cdiv = div; writel(host->cdiv, host->ioaddr + SDCDIV); /* Set the timeout to 500ms */ writel(mmc->actual_clock / 2, host->ioaddr + SDTOUT); } static void bcm2835_request(struct mmc_host *mmc, struct mmc_request *mrq) { struct bcm2835_host *host = mmc_priv(mmc); struct device *dev = &host->pdev->dev; u32 edm, fsm; /* 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)) { dev_err(dev, "unsupported block size (%d bytes)\n", mrq->data->blksz); if (mrq->cmd) mrq->cmd->error = -EINVAL; mmc_request_done(mmc, mrq); return; } mutex_lock(&host->mutex); WARN_ON(host->mrq); host->mrq = mrq; edm = readl(host->ioaddr + SDEDM); fsm = edm & SDEDM_FSM_MASK; if ((fsm != SDEDM_FSM_IDENTMODE) && (fsm != SDEDM_FSM_DATAMODE)) { dev_err(dev, "previous command (%d) not complete (EDM %08x)\n", readl(host->ioaddr + SDCMD) & SDCMD_CMD_MASK, edm); bcm2835_dumpregs(host); if (mrq->cmd) mrq->cmd->error = -EILSEQ; bcm2835_finish_request(host); mutex_unlock(&host->mutex); return; } if (host->use_dma && mrq->data && (mrq->data->blocks > PIO_THRESHOLD)) bcm2835_prepare_dma(host, mrq->data); host->use_sbc = !!mrq->sbc && host->mrq->data && (host->mrq->data->flags & MMC_DATA_READ); if (host->use_sbc) { if (bcm2835_send_command(host, mrq->sbc)) { if (!host->use_busy) bcm2835_finish_command(host); } } else if (mrq->cmd && bcm2835_send_command(host, mrq->cmd)) { if (host->data && host->dma_desc) { /* DMA transfer starts now, PIO starts after irq */ bcm2835_start_dma(host); } if (!host->use_busy) bcm2835_finish_command(host); } mutex_unlock(&host->mutex); } static void bcm2835_set_ios(struct mmc_host *mmc, struct mmc_ios *ios) { struct bcm2835_host *host = mmc_priv(mmc); mutex_lock(&host->mutex); if (!ios->clock || ios->clock != host->clock) { bcm2835_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; writel(host->hcfg, host->ioaddr + SDHCFG); mutex_unlock(&host->mutex); } static const struct mmc_host_ops bcm2835_ops = { .request = bcm2835_request, .set_ios = bcm2835_set_ios, .hw_reset = bcm2835_reset, }; static int bcm2835_add_host(struct bcm2835_host *host) { struct mmc_host *mmc = mmc_from_priv(host); struct device *dev = &host->pdev->dev; char pio_limit_string[20]; int ret; if (!mmc->f_max || mmc->f_max > host->max_clk) mmc->f_max = host->max_clk; mmc->f_min = host->max_clk / SDCDIV_MAX_CDIV; mmc->max_busy_timeout = ~0 / (mmc->f_max / 1000); dev_dbg(dev, "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); mutex_init(&host->mutex); if (!host->dma_chan_rxtx) { dev_warn(dev, "unable to initialise DMA channel. Falling back to PIO\n"); host->use_dma = false; } else { host->use_dma = true; host->dma_cfg_tx.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; host->dma_cfg_tx.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; host->dma_cfg_tx.slave_id = 13; /* DREQ channel */ host->dma_cfg_tx.direction = DMA_MEM_TO_DEV; host->dma_cfg_tx.src_addr = 0; host->dma_cfg_tx.dst_addr = host->phys_addr + SDDATA; host->dma_cfg_rx.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; host->dma_cfg_rx.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; host->dma_cfg_rx.slave_id = 13; /* DREQ channel */ host->dma_cfg_rx.direction = DMA_DEV_TO_MEM; host->dma_cfg_rx.src_addr = host->phys_addr + SDDATA; host->dma_cfg_rx.dst_addr = 0; if (dmaengine_slave_config(host->dma_chan_rxtx, &host->dma_cfg_tx) != 0 || dmaengine_slave_config(host->dma_chan_rxtx, &host->dma_cfg_rx) != 0) host->use_dma = false; } mmc->max_segs = 128; mmc->max_req_size = min_t(size_t, 524288, dma_max_mapping_size(dev)); mmc->max_seg_size = mmc->max_req_size; mmc->max_blk_size = 1024; mmc->max_blk_count = 65535; /* report supported voltage ranges */ mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34; INIT_WORK(&host->dma_work, bcm2835_dma_complete_work); INIT_DELAYED_WORK(&host->timeout_work, bcm2835_timeout); /* Set interrupt enables */ host->hcfg = SDHCFG_BUSY_IRPT_EN; bcm2835_reset_internal(host); ret = request_threaded_irq(host->irq, bcm2835_irq, bcm2835_threaded_irq, 0, mmc_hostname(mmc), host); if (ret) { dev_err(dev, "failed to request IRQ %d: %d\n", host->irq, ret); return ret; } ret = mmc_add_host(mmc); if (ret) { free_irq(host->irq, host); return ret; } pio_limit_string[0] = '\0'; if (host->use_dma && (PIO_THRESHOLD > 0)) sprintf(pio_limit_string, " (>%d)", PIO_THRESHOLD); dev_info(dev, "loaded - DMA %s%s\n", host->use_dma ? "enabled" : "disabled", pio_limit_string); return 0; } static int bcm2835_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; struct clk *clk; struct bcm2835_host *host; struct mmc_host *mmc; const __be32 *regaddr_p; int ret; dev_dbg(dev, "%s\n", __func__); mmc = mmc_alloc_host(sizeof(*host), dev); if (!mmc) return -ENOMEM; mmc->ops = &bcm2835_ops; host = mmc_priv(mmc); host->pdev = pdev; spin_lock_init(&host->lock); host->ioaddr = devm_platform_ioremap_resource(pdev, 0); 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. */ regaddr_p = of_get_address(pdev->dev.of_node, 0, NULL, NULL); if (!regaddr_p) { dev_err(dev, "Can't get phys address\n"); ret = -EINVAL; goto err; } host->phys_addr = be32_to_cpup(regaddr_p); host->dma_chan = NULL; host->dma_desc = NULL; host->dma_chan_rxtx = dma_request_chan(dev, "rx-tx"); if (IS_ERR(host->dma_chan_rxtx)) { ret = PTR_ERR(host->dma_chan_rxtx); host->dma_chan_rxtx = NULL; if (ret == -EPROBE_DEFER) goto err; /* Ignore errors to fall back to PIO mode */ } 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) { ret = -EINVAL; goto err; } ret = mmc_of_parse(mmc); if (ret) goto err; ret = bcm2835_add_host(host); if (ret) goto err; platform_set_drvdata(pdev, host); dev_dbg(dev, "%s -> OK\n", __func__); return 0; err: dev_dbg(dev, "%s -> err %d\n", __func__, ret); if (host->dma_chan_rxtx) dma_release_channel(host->dma_chan_rxtx); mmc_free_host(mmc); return ret; } static int bcm2835_remove(struct platform_device *pdev) { struct bcm2835_host *host = platform_get_drvdata(pdev); struct mmc_host *mmc = mmc_from_priv(host); mmc_remove_host(mmc); writel(SDVDD_POWER_OFF, host->ioaddr + SDVDD); free_irq(host->irq, host); cancel_work_sync(&host->dma_work); cancel_delayed_work_sync(&host->timeout_work); if (host->dma_chan_rxtx) dma_release_channel(host->dma_chan_rxtx); mmc_free_host(mmc); return 0; } static const struct of_device_id bcm2835_match[] = { { .compatible = "brcm,bcm2835-sdhost" }, { } }; MODULE_DEVICE_TABLE(of, bcm2835_match); static struct platform_driver bcm2835_driver = { .probe = bcm2835_probe, .remove = bcm2835_remove, .driver = { .name = "sdhost-bcm2835", .of_match_table = bcm2835_match, }, }; module_platform_driver(bcm2835_driver); MODULE_ALIAS("platform:sdhost-bcm2835"); MODULE_DESCRIPTION("BCM2835 SDHost driver"); MODULE_LICENSE("GPL v2"); MODULE_AUTHOR("Phil Elwell");
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