This patch implements pre_req and post_req in dw_mmc
to support asynchronous mmc request.
Signed-off-by: Seungwon Jeon <tgih.jun@xxxxxxxxxxx>
---
Changes in v3:
Rebase with latest mmc-next.
Changes in v2:
Consider system DMA case as well as IDMAC.
NOTE:
Performance gains the following.
Sequential read and write improve 23% and 5% respectively.
drivers/mmc/host/dw_mmc.c | 129 +++++++++++++++++++++++++++++++++++---------
1 files changed, 102 insertions(+), 27 deletions(-)
diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c
index 9188489..dee839e 100644
--- a/drivers/mmc/host/dw_mmc.c
+++ b/drivers/mmc/host/dw_mmc.c
@@ -297,14 +297,24 @@ static void dw_mci_stop_dma(struct dw_mci *host)
}
#ifdef CONFIG_MMC_DW_IDMAC
+static int dw_mci_get_dma_dir(struct mmc_data *data)
+{
+ if (data->flags & MMC_DATA_WRITE)
+ return DMA_TO_DEVICE;
+ else
+ return DMA_FROM_DEVICE;
+}
+
static void dw_mci_dma_cleanup(struct dw_mci *host)
{
struct mmc_data *data = host->data;
if (data)
- dma_unmap_sg(&host->dev, data->sg, data->sg_len,
- ((data->flags & MMC_DATA_WRITE)
- ? DMA_TO_DEVICE : DMA_FROM_DEVICE));
+ if (!data->host_cookie)
+ dma_unmap_sg(&host->dev,
+ data->sg,
+ data->sg_len,
+ dw_mci_get_dma_dir(data));
}
static void dw_mci_idmac_stop_dma(struct dw_mci *host)
@@ -420,26 +430,15 @@ static int dw_mci_idmac_init(struct dw_mci *host)
return 0;
}
-static struct dw_mci_dma_ops dw_mci_idmac_ops = {
- .init = dw_mci_idmac_init,
- .start = dw_mci_idmac_start_dma,
- .stop = dw_mci_idmac_stop_dma,
- .complete = dw_mci_idmac_complete_dma,
- .cleanup = dw_mci_dma_cleanup,
-};
-#endif /* CONFIG_MMC_DW_IDMAC */
-
-static int dw_mci_submit_data_dma(struct dw_mci *host, struct mmc_data *data)
+static int dw_mci_pre_dma_transfer(struct dw_mci *host,
+ struct mmc_data *data,
+ bool next)
{
struct scatterlist *sg;
- unsigned int i, direction, sg_len;
- u32 temp;
-
- host->using_dma = 0;
+ unsigned int i, sg_len;
- /* If we don't have a channel, we can't do DMA */
- if (!host->use_dma)
- return -ENODEV;
+ if (!next && data->host_cookie)
+ return data->host_cookie;
/*
* We don't do DMA on "complex" transfers, i.e. with
@@ -448,6 +447,7 @@ static int dw_mci_submit_data_dma(struct dw_mci *host, struct mmc_data *data)
*/
if (data->blocks * data->blksz < DW_MCI_DMA_THRESHOLD)
return -EINVAL;
+
if (data->blksz & 3)
return -EINVAL;
@@ -456,15 +456,88 @@ static int dw_mci_submit_data_dma(struct dw_mci *host, struct mmc_data *data)
return -EINVAL;
}
- host->using_dma = 1;
+ sg_len = dma_map_sg(&host->dev,
+ data->sg,
+ data->sg_len,
+ dw_mci_get_dma_dir(data));
+ if (sg_len == 0)
+ return -EINVAL;
- if (data->flags & MMC_DATA_READ)
- direction = DMA_FROM_DEVICE;
- else
- direction = DMA_TO_DEVICE;
+ if (next)
+ data->host_cookie = sg_len;
+
+ return sg_len;
+}
+
+static struct dw_mci_dma_ops dw_mci_idmac_ops = {
+ .init = dw_mci_idmac_init,
+ .start = dw_mci_idmac_start_dma,
+ .stop = dw_mci_idmac_stop_dma,
+ .complete = dw_mci_idmac_complete_dma,
+ .cleanup = dw_mci_dma_cleanup,
+};
+#else
+static int dw_mci_pre_dma_transfer(struct dw_mci *host,
+ struct mmc_data *data,
+ bool next)
+{
+ return -ENOSYS;
+}
+#endif /* CONFIG_MMC_DW_IDMAC */
+
+static void dw_mci_pre_req(struct mmc_host *mmc,
+ struct mmc_request *mrq,
+ bool is_first_req)
+{
+ struct dw_mci_slot *slot = mmc_priv(mmc);
+ struct mmc_data *data = mrq->data;
+
+ if (!slot->host->use_dma || !data)
+ return;
+
+ if (data->host_cookie) {
+ data->host_cookie = 0;
+ return;
+ }
+
+ if (dw_mci_pre_dma_transfer(slot->host, mrq->data, 1) < 0)
+ data->host_cookie = 0;
+}
+
+static void dw_mci_post_req(struct mmc_host *mmc,
+ struct mmc_request *mrq,
+ int err)
+{
+ struct dw_mci_slot *slot = mmc_priv(mmc);
+ struct mmc_data *data = mrq->data;
+
+ if (!slot->host->use_dma || !data)
+ return;
+
+ if (data->host_cookie)
+ dma_unmap_sg(&slot->host->dev,
+ data->sg,
+ data->sg_len,
+ dw_mci_get_dma_dir(data));
+ data->host_cookie = 0;
+}
+
+static int dw_mci_submit_data_dma(struct dw_mci *host, struct mmc_data *data)
+{
+ int sg_len;
+ u32 temp;
- sg_len = dma_map_sg(&host->dev, data->sg, data->sg_len,
- direction);
+ host->using_dma = 0;
+
+ /* If we don't have a channel, we can't do DMA */
+ if (!host->use_dma)
+ return -ENODEV;
+
+ sg_len = dw_mci_pre_dma_transfer(host, data, 0);
+ if (sg_len < 0)
+ return sg_len;
+
+ host->using_dma = 1;
dev_vdbg(&host->dev,
"sd sg_cpu: %#lx sg_dma: %#lx sg_len: %d\n",
@@ -795,6 +868,8 @@ static void dw_mci_enable_sdio_irq(struct mmc_host *mmc, int enb)
static const struct mmc_host_ops dw_mci_ops = {
.request = dw_mci_request,
+ .pre_req = dw_mci_pre_req,
+ .post_req = dw_mci_post_req,
.set_ios = dw_mci_set_ios,
.get_ro = dw_mci_get_ro,
.get_cd = dw_mci_get_cd,
--
1.7.0.4
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