diff options
Diffstat (limited to 'drivers/mmc/host/renesas_sdhi_internal_dmac.c')
| -rw-r--r-- | drivers/mmc/host/renesas_sdhi_internal_dmac.c | 39 |
1 files changed, 33 insertions, 6 deletions
diff --git a/drivers/mmc/host/renesas_sdhi_internal_dmac.c b/drivers/mmc/host/renesas_sdhi_internal_dmac.c index 8e0acd197c43..6af946d16d24 100644 --- a/drivers/mmc/host/renesas_sdhi_internal_dmac.c +++ b/drivers/mmc/host/renesas_sdhi_internal_dmac.c @@ -9,6 +9,7 @@ * published by the Free Software Foundation. */ +#include <linux/bitops.h> #include <linux/device.h> #include <linux/dma-mapping.h> #include <linux/io-64-nonatomic-hi-lo.h> @@ -62,6 +63,17 @@ * need a custom accessor. */ +static unsigned long global_flags; +/* + * Workaround for avoiding to use RX DMAC by multiple channels. + * On R-Car H3 ES1.* and M3-W ES1.0, when multiple SDHI channels use + * RX DMAC simultaneously, sometimes hundreds of bytes data are not + * stored into the system memory even if the DMAC interrupt happened. + * So, this driver then uses one RX DMAC channel only. + */ +#define SDHI_INTERNAL_DMAC_ONE_RX_ONLY 0 +#define SDHI_INTERNAL_DMAC_RX_IN_USE 1 + /* Definitions for sampling clocks */ static struct renesas_sdhi_scc rcar_gen3_scc_taps[] = { { @@ -126,6 +138,9 @@ renesas_sdhi_internal_dmac_abort_dma(struct tmio_mmc_host *host) { renesas_sdhi_internal_dmac_dm_write(host, DM_CM_RST, RST_RESERVED_BITS | val); + if (host->data && host->data->flags & MMC_DATA_READ) + clear_bit(SDHI_INTERNAL_DMAC_RX_IN_USE, &global_flags); + renesas_sdhi_internal_dmac_enable_dma(host, true); } @@ -155,6 +170,9 @@ renesas_sdhi_internal_dmac_start_dma(struct tmio_mmc_host *host, if (data->flags & MMC_DATA_READ) { dtran_mode |= DTRAN_MODE_CH_NUM_CH1; dir = DMA_FROM_DEVICE; + if (test_bit(SDHI_INTERNAL_DMAC_ONE_RX_ONLY, &global_flags) && + test_and_set_bit(SDHI_INTERNAL_DMAC_RX_IN_USE, &global_flags)) + goto force_pio; } else { dtran_mode |= DTRAN_MODE_CH_NUM_CH0; dir = DMA_TO_DEVICE; @@ -208,6 +226,9 @@ static void renesas_sdhi_internal_dmac_complete_tasklet_fn(unsigned long arg) renesas_sdhi_internal_dmac_enable_dma(host, false); dma_unmap_sg(&host->pdev->dev, host->sg_ptr, host->sg_len, dir); + if (dir == DMA_FROM_DEVICE) + clear_bit(SDHI_INTERNAL_DMAC_RX_IN_USE, &global_flags); + tmio_mmc_do_data_irq(host); out: spin_unlock_irq(&host->lock); @@ -251,18 +272,24 @@ static const struct tmio_mmc_dma_ops renesas_sdhi_internal_dmac_dma_ops = { * implementation as others may use a different implementation. */ static const struct soc_device_attribute gen3_soc_whitelist[] = { - { .soc_id = "r8a7795", .revision = "ES1.*" }, - { .soc_id = "r8a7795", .revision = "ES2.0" }, - { .soc_id = "r8a7796", .revision = "ES1.0" }, - { .soc_id = "r8a77995", .revision = "ES1.0" }, - { /* sentinel */ } + { .soc_id = "r8a7795", .revision = "ES1.*", + .data = (void *)BIT(SDHI_INTERNAL_DMAC_ONE_RX_ONLY) }, + { .soc_id = "r8a7795", .revision = "ES2.0" }, + { .soc_id = "r8a7796", .revision = "ES1.0", + .data = (void *)BIT(SDHI_INTERNAL_DMAC_ONE_RX_ONLY) }, + { .soc_id = "r8a77995", .revision = "ES1.0" }, + { /* sentinel */ } }; static int renesas_sdhi_internal_dmac_probe(struct platform_device *pdev) { - if (!soc_device_match(gen3_soc_whitelist)) + const struct soc_device_attribute *soc = soc_device_match(gen3_soc_whitelist); + + if (!soc) return -ENODEV; + global_flags |= (unsigned long)soc->data; + return renesas_sdhi_probe(pdev, &renesas_sdhi_internal_dmac_dma_ops); } |