This change helps to choose msize, rx_watermark and
tx_watermak depending on block size for IDMAC mode.
For SDIO block size can be variable, so if these values
are set incorrectly, card clock may stop.
Signed-off-by: Seungwon Jeon <tgih.jun@xxxxxxxxxxx>
---
drivers/mmc/host/dw_mmc.c | 74 ++++++++++++++++++++++++++++++++++++++++++--
drivers/mmc/host/dw_mmc.h | 4 ++
include/linux/mmc/dw_mmc.h | 1 +
3 files changed, 76 insertions(+), 3 deletions(-)
diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c
index 296d4a4..b8ba707 100644
--- a/drivers/mmc/host/dw_mmc.c
+++ b/drivers/mmc/host/dw_mmc.c
@@ -529,6 +529,47 @@ static void dw_mci_post_req(struct mmc_host *mmc,
data->host_cookie = 0;
}
+static void dw_mci_adjust_fifoth(struct dw_mci *host, struct mmc_data *data)
+{
+#ifdef CONFIG_MMC_DW_IDMAC
+ unsigned int blksz = data->blksz;
+ const u32 mszs[] = {1, 4, 8, 16, 32, 64, 128, 256};
+ u32 fifo_width = 1 << host->data_shift;
+ u32 blksz_depth = blksz / fifo_width, fifoth_val;
+ u32 msize = 0, rx_wmark = 1, tx_wmark, tx_wmark_invers;
+ int idx = (sizeof(mszs) / sizeof(mszs[0])) - 1;
+
+ tx_wmark = (host->fifo_depth) / 2;
+ tx_wmark_invers = host->fifo_depth - tx_wmark;
+
+ /*
+ * MSIZE is '1',
+ * if blksz is not a multiple of the FIFO width
+ */
+ if (blksz % fifo_width) {
+ msize = 0;
+ rx_wmark = 1;
+ goto done;
+ }
+
+ do {
+ if (!((blksz_depth % mszs[idx]) ||
+ (tx_wmark_invers % mszs[idx]))) {
+ msize = idx;
+ rx_wmark = mszs[idx] - 1;
+ break;
+ }
+ } while (--idx > 0);
+ /*
+ * If idx is '0', it won't be tried
+ * Thus, initial values are uesed
+ */
+done:
+ fifoth_val = SDMMC_SET_FIFOTH(msize, rx_wmark, tx_wmark);
+ mci_writel(host, FIFOTH, fifoth_val);
+#endif
+}
+
static int dw_mci_submit_data_dma(struct dw_mci *host, struct mmc_data *data)
{
int sg_len;
@@ -553,6 +594,14 @@ static int dw_mci_submit_data_dma(struct dw_mci *host, struct mmc_data *data)
(unsigned long)host->sg_cpu, (unsigned long)host->sg_dma,
sg_len);
+ /*
+ * Decide the MSIZE and RX/TX Watermark.
+ * If current block size is same with previous size,
+ * no need to update fifoth.
+ */
+ if (host->prev_blksz != data->blksz)
+ dw_mci_adjust_fifoth(host, data);
+
/* Enable the DMA interface */
temp = mci_readl(host, CTRL);
temp |= SDMMC_CTRL_DMA_ENABLE;
@@ -603,6 +652,21 @@ static void dw_mci_submit_data(struct dw_mci *host, struct mmc_data *data)
temp = mci_readl(host, CTRL);
temp &= ~SDMMC_CTRL_DMA_ENABLE;
mci_writel(host, CTRL, temp);
+
+ /*
+ * Use the initial fifoth_val for PIO mode.
+ * If next issued data may be transfered by DMA mode,
+ * prev_blksz should be invalidated.
+ */
+ mci_writel(host, FIFOTH, host->fifoth_val);
+ host->prev_blksz = 0;
+ } else {
+ /*
+ * Keep the current block size.
+ * It will be used to decide whether to update
+ * fifoth register next time.
+ */
+ host->prev_blksz = data->blksz;
}
}
@@ -2358,8 +2422,8 @@ int dw_mci_probe(struct dw_mci *host)
fifo_size = host->pdata->fifo_depth;
}
host->fifo_depth = fifo_size;
- host->fifoth_val = ((0x2 << 28) | ((fifo_size/2 - 1) << 16) |
- ((fifo_size/2) << 0));
+ host->fifoth_val =
+ SDMMC_SET_FIFOTH(0x2, fifo_size / 2 - 1, fifo_size / 2);
mci_writel(host, FIFOTH, host->fifoth_val);
/* disable clock to CIU */
@@ -2542,8 +2606,12 @@ int dw_mci_resume(struct dw_mci *host)
if (host->use_dma && host->dma_ops->init)
host->dma_ops->init(host);
- /* Restore the old value at FIFOTH register */
+ /*
+ * Restore the initial value at FIFOTH register
+ * And Invalidate the prev_blksz with zero
+ */
mci_writel(host, FIFOTH, host->fifoth_val);
+ host->prev_blksz = 0;
mci_writel(host, RINTSTS, 0xFFFFFFFF);
mci_writel(host, INTMASK, SDMMC_INT_CMD_DONE | SDMMC_INT_DATA_OVER |
diff --git a/drivers/mmc/host/dw_mmc.h b/drivers/mmc/host/dw_mmc.h
index 661c6f9..4002c84 100644
--- a/drivers/mmc/host/dw_mmc.h
+++ b/drivers/mmc/host/dw_mmc.h
@@ -128,6 +128,10 @@
#define SDMMC_CMD_INDX(n) ((n) & 0x1F)
/* Status register defines */
#define SDMMC_GET_FCNT(x) (((x)>>17) & 0x1FFF)
+/* FIFOTH register defines */
+#define SDMMC_SET_FIFOTH(m, r, t) (((m) & 0x7) << 28 | \
+ ((r) & 0xFFF) << 16 | \
+ ((t) & 0xFFF))
/* Internal DMAC interrupt defines */
#define SDMMC_IDMAC_INT_AI BIT(9)
#define SDMMC_IDMAC_INT_NI BIT(8)
diff --git a/include/linux/mmc/dw_mmc.h b/include/linux/mmc/dw_mmc.h
index 198f0fa..4ec9dcc 100644
--- a/include/linux/mmc/dw_mmc.h
+++ b/include/linux/mmc/dw_mmc.h
@@ -129,6 +129,7 @@ struct dw_mci {
struct mmc_request *mrq;
struct mmc_command *cmd;
struct mmc_data *data;
+ unsigned int prev_blksz;
struct workqueue_struct *card_workqueue;
/* DMA interface members*/
--
1.7.0.4
--
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