From b5daabbd3d1803cbb4ba89bde3968891dd4e1d1c Mon Sep 17 00:00:00 2001 From: Matt Porter Date: Wed, 22 Aug 2012 21:09:35 -0400 Subject: [PATCH] mmc: davinci_mmc: convert to DMA engine API Removes use of the DaVinci EDMA private DMA API and replaces it with use of the DMA engine API. Signed-off-by: Matt Porter Tested-by: Tom Rini Tested-by: Sekhar Nori Signed-off-by: Vinod Koul --- drivers/mmc/host/davinci_mmc.c | 271 ++++++++++----------------------- 1 file changed, 82 insertions(+), 189 deletions(-) diff --git a/drivers/mmc/host/davinci_mmc.c b/drivers/mmc/host/davinci_mmc.c index 7cf6c624bf73..c5e1eebcd588 100644 --- a/drivers/mmc/host/davinci_mmc.c +++ b/drivers/mmc/host/davinci_mmc.c @@ -30,11 +30,12 @@ #include #include #include +#include #include +#include #include #include -#include /* * Register Definitions @@ -200,21 +201,13 @@ struct mmc_davinci_host { u32 bytes_left; u32 rxdma, txdma; + struct dma_chan *dma_tx; + struct dma_chan *dma_rx; bool use_dma; bool do_dma; bool sdio_int; bool active_request; - /* Scatterlist DMA uses one or more parameter RAM entries: - * the main one (associated with rxdma or txdma) plus zero or - * more links. The entries for a given transfer differ only - * by memory buffer (address, length) and link field. - */ - struct edmacc_param tx_template; - struct edmacc_param rx_template; - unsigned n_link; - u32 links[MAX_NR_SG - 1]; - /* For PIO we walk scatterlists one segment at a time. */ unsigned int sg_len; struct scatterlist *sg; @@ -410,153 +403,74 @@ static void mmc_davinci_start_command(struct mmc_davinci_host *host, static void davinci_abort_dma(struct mmc_davinci_host *host) { - int sync_dev; + struct dma_chan *sync_dev; if (host->data_dir == DAVINCI_MMC_DATADIR_READ) - sync_dev = host->rxdma; + sync_dev = host->dma_rx; else - sync_dev = host->txdma; - - edma_stop(sync_dev); - edma_clean_channel(sync_dev); -} - -static void -mmc_davinci_xfer_done(struct mmc_davinci_host *host, struct mmc_data *data); - -static void mmc_davinci_dma_cb(unsigned channel, u16 ch_status, void *data) -{ - if (DMA_COMPLETE != ch_status) { - struct mmc_davinci_host *host = data; - - /* Currently means: DMA Event Missed, or "null" transfer - * request was seen. In the future, TC errors (like bad - * addresses) might be presented too. - */ - dev_warn(mmc_dev(host->mmc), "DMA %s error\n", - (host->data->flags & MMC_DATA_WRITE) - ? "write" : "read"); - host->data->error = -EIO; - mmc_davinci_xfer_done(host, host->data); - } -} - -/* Set up tx or rx template, to be modified and updated later */ -static void __init mmc_davinci_dma_setup(struct mmc_davinci_host *host, - bool tx, struct edmacc_param *template) -{ - unsigned sync_dev; - const u16 acnt = 4; - const u16 bcnt = rw_threshold >> 2; - const u16 ccnt = 0; - u32 src_port = 0; - u32 dst_port = 0; - s16 src_bidx, dst_bidx; - s16 src_cidx, dst_cidx; - - /* - * A-B Sync transfer: each DMA request is for one "frame" of - * rw_threshold bytes, broken into "acnt"-size chunks repeated - * "bcnt" times. Each segment needs "ccnt" such frames; since - * we tell the block layer our mmc->max_seg_size limit, we can - * trust (later) that it's within bounds. - * - * The FIFOs are read/written in 4-byte chunks (acnt == 4) and - * EDMA will optimize memory operations to use larger bursts. - */ - if (tx) { - sync_dev = host->txdma; - - /* src_prt, ccnt, and link to be set up later */ - src_bidx = acnt; - src_cidx = acnt * bcnt; - - dst_port = host->mem_res->start + DAVINCI_MMCDXR; - dst_bidx = 0; - dst_cidx = 0; - } else { - sync_dev = host->rxdma; - - src_port = host->mem_res->start + DAVINCI_MMCDRR; - src_bidx = 0; - src_cidx = 0; - - /* dst_prt, ccnt, and link to be set up later */ - dst_bidx = acnt; - dst_cidx = acnt * bcnt; - } - - /* - * We can't use FIFO mode for the FIFOs because MMC FIFO addresses - * are not 256-bit (32-byte) aligned. So we use INCR, and the W8BIT - * parameter is ignored. - */ - edma_set_src(sync_dev, src_port, INCR, W8BIT); - edma_set_dest(sync_dev, dst_port, INCR, W8BIT); + sync_dev = host->dma_tx; - edma_set_src_index(sync_dev, src_bidx, src_cidx); - edma_set_dest_index(sync_dev, dst_bidx, dst_cidx); - - edma_set_transfer_params(sync_dev, acnt, bcnt, ccnt, 8, ABSYNC); - - edma_read_slot(sync_dev, template); - - /* don't bother with irqs or chaining */ - template->opt |= EDMA_CHAN_SLOT(sync_dev) << 12; + dmaengine_terminate_all(sync_dev); } -static void mmc_davinci_send_dma_request(struct mmc_davinci_host *host, +static int mmc_davinci_send_dma_request(struct mmc_davinci_host *host, struct mmc_data *data) { - struct edmacc_param *template; - int channel, slot; - unsigned link; - struct scatterlist *sg; - unsigned sg_len; - unsigned bytes_left = host->bytes_left; - const unsigned shift = ffs(rw_threshold) - 1; + struct dma_chan *chan; + struct dma_async_tx_descriptor *desc; + int ret = 0; if (host->data_dir == DAVINCI_MMC_DATADIR_WRITE) { - template = &host->tx_template; - channel = host->txdma; + struct dma_slave_config dma_tx_conf = { + .direction = DMA_MEM_TO_DEV, + .dst_addr = host->mem_res->start + DAVINCI_MMCDXR, + .dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES, + .dst_maxburst = + rw_threshold / DMA_SLAVE_BUSWIDTH_4_BYTES, + }; + chan = host->dma_tx; + dmaengine_slave_config(host->dma_tx, &dma_tx_conf); + + desc = dmaengine_prep_slave_sg(host->dma_tx, + data->sg, + host->sg_len, + DMA_MEM_TO_DEV, + DMA_PREP_INTERRUPT | DMA_CTRL_ACK); + if (!desc) { + dev_dbg(mmc_dev(host->mmc), + "failed to allocate DMA TX descriptor"); + ret = -1; + goto out; + } } else { - template = &host->rx_template; - channel = host->rxdma; - } - - /* We know sg_len and ccnt will never be out of range because - * we told the mmc layer which in turn tells the block layer - * to ensure that it only hands us one scatterlist segment - * per EDMA PARAM entry. Update the PARAM - * entries needed for each segment of this scatterlist. - */ - for (slot = channel, link = 0, sg = data->sg, sg_len = host->sg_len; - sg_len-- != 0 && bytes_left; - sg = sg_next(sg), slot = host->links[link++]) { - u32 buf = sg_dma_address(sg); - unsigned count = sg_dma_len(sg); - - template->link_bcntrld = sg_len - ? (EDMA_CHAN_SLOT(host->links[link]) << 5) - : 0xffff; - - if (count > bytes_left) - count = bytes_left; - bytes_left -= count; - - if (host->data_dir == DAVINCI_MMC_DATADIR_WRITE) - template->src = buf; - else - template->dst = buf; - template->ccnt = count >> shift; - - edma_write_slot(slot, template); + struct dma_slave_config dma_rx_conf = { + .direction = DMA_DEV_TO_MEM, + .src_addr = host->mem_res->start + DAVINCI_MMCDRR, + .src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES, + .src_maxburst = + rw_threshold / DMA_SLAVE_BUSWIDTH_4_BYTES, + }; + chan = host->dma_rx; + dmaengine_slave_config(host->dma_rx, &dma_rx_conf); + + desc = dmaengine_prep_slave_sg(host->dma_rx, + data->sg, + host->sg_len, + DMA_DEV_TO_MEM, + DMA_PREP_INTERRUPT | DMA_CTRL_ACK); + if (!desc) { + dev_dbg(mmc_dev(host->mmc), + "failed to allocate DMA RX descriptor"); + ret = -1; + goto out; + } } - if (host->version == MMC_CTLR_VERSION_2) - edma_clear_event(channel); + dmaengine_submit(desc); + dma_async_issue_pending(chan); - edma_start(channel); +out: + return ret; } static int mmc_davinci_start_dma_transfer(struct mmc_davinci_host *host, @@ -564,6 +478,7 @@ static int mmc_davinci_start_dma_transfer(struct mmc_davinci_host *host, { int i; int mask = rw_threshold - 1; + int ret = 0; host->sg_len = dma_map_sg(mmc_dev(host->mmc), data->sg, data->sg_len, ((data->flags & MMC_DATA_WRITE) @@ -583,70 +498,48 @@ static int mmc_davinci_start_dma_transfer(struct mmc_davinci_host *host, } host->do_dma = 1; - mmc_davinci_send_dma_request(host, data); + ret = mmc_davinci_send_dma_request(host, data); - return 0; + return ret; } static void __init_or_module davinci_release_dma_channels(struct mmc_davinci_host *host) { - unsigned i; - if (!host->use_dma) return; - for (i = 0; i < host->n_link; i++) - edma_free_slot(host->links[i]); - - edma_free_channel(host->txdma); - edma_free_channel(host->rxdma); + dma_release_channel(host->dma_tx); + dma_release_channel(host->dma_rx); } static int __init davinci_acquire_dma_channels(struct mmc_davinci_host *host) { - u32 link_size; - int r, i; - - /* Acquire master DMA write channel */ - r = edma_alloc_channel(host->txdma, mmc_davinci_dma_cb, host, - EVENTQ_DEFAULT); - if (r < 0) { - dev_warn(mmc_dev(host->mmc), "alloc %s channel err %d\n", - "tx", r); - return r; - } - mmc_davinci_dma_setup(host, true, &host->tx_template); - - /* Acquire master DMA read channel */ - r = edma_alloc_channel(host->rxdma, mmc_davinci_dma_cb, host, - EVENTQ_DEFAULT); - if (r < 0) { - dev_warn(mmc_dev(host->mmc), "alloc %s channel err %d\n", - "rx", r); - goto free_master_write; + int r; + dma_cap_mask_t mask; + + dma_cap_zero(mask); + dma_cap_set(DMA_SLAVE, mask); + + host->dma_tx = + dma_request_channel(mask, edma_filter_fn, &host->txdma); + if (!host->dma_tx) { + dev_err(mmc_dev(host->mmc), "Can't get dma_tx channel\n"); + return -ENODEV; } - mmc_davinci_dma_setup(host, false, &host->rx_template); - /* Allocate parameter RAM slots, which will later be bound to a - * channel as needed to handle a scatterlist. - */ - link_size = min_t(unsigned, host->nr_sg, ARRAY_SIZE(host->links)); - for (i = 0; i < link_size; i++) { - r = edma_alloc_slot(EDMA_CTLR(host->txdma), EDMA_SLOT_ANY); - if (r < 0) { - dev_dbg(mmc_dev(host->mmc), "dma PaRAM alloc --> %d\n", - r); - break; - } - host->links[i] = r; + host->dma_rx = + dma_request_channel(mask, edma_filter_fn, &host->rxdma); + if (!host->dma_rx) { + dev_err(mmc_dev(host->mmc), "Can't get dma_rx channel\n"); + r = -ENODEV; + goto free_master_write; } - host->n_link = i; return 0; free_master_write: - edma_free_channel(host->txdma); + dma_release_channel(host->dma_tx); return r; } @@ -1359,7 +1252,7 @@ static int __init davinci_mmcsd_probe(struct platform_device *pdev) * Each hw_seg uses one EDMA parameter RAM slot, always one * channel and then usually some linked slots. */ - mmc->max_segs = 1 + host->n_link; + mmc->max_segs = MAX_NR_SG; /* EDMA limit per hw segment (one or two MBytes) */ mmc->max_seg_size = MAX_CCNT * rw_threshold; -- 2.30.2