@@ -131,12 +131,10 @@ struct moxart_host {
struct dma_async_tx_descriptor *tx_desc;
struct mmc_host *mmc;
struct mmc_request *mrq;
- struct scatterlist *cur_sg;
struct completion dma_complete;
struct completion pio_complete;
- u32 num_sg;
- u32 data_remain;
+ struct sg_mapping_iter sg_miter;
u32 data_len;
u32 fifo_width;
u32 timeout;
@@ -148,35 +146,6 @@ struct moxart_host {
bool is_removed;
};
-static inline void moxart_init_sg(struct moxart_host *host,
- struct mmc_data *data)
-{
- host->cur_sg = data->sg;
- host->num_sg = data->sg_len;
- host->data_remain = host->cur_sg->length;
-
- if (host->data_remain > host->data_len)
- host->data_remain = host->data_len;
-}
-
-static inline int moxart_next_sg(struct moxart_host *host)
-{
- int remain;
- struct mmc_data *data = host->mrq->cmd->data;
-
- host->cur_sg++;
- host->num_sg--;
-
- if (host->num_sg > 0) {
- host->data_remain = host->cur_sg->length;
- remain = host->data_len - data->bytes_xfered;
- if (remain > 0 && remain < host->data_remain)
- host->data_remain = remain;
- }
-
- return host->num_sg;
-}
-
static int moxart_wait_for_status(struct moxart_host *host,
u32 mask, u32 *status)
{
@@ -309,14 +278,28 @@ static void moxart_transfer_dma(struct mmc_data *data, struct moxart_host *host)
static void moxart_transfer_pio(struct moxart_host *host)
{
+ struct sg_mapping_iter *sgm = &host->sg_miter;
struct mmc_data *data = host->mrq->cmd->data;
u32 *sgp, len = 0, remain, status;
if (host->data_len == data->bytes_xfered)
return;
- sgp = sg_virt(host->cur_sg);
- remain = host->data_remain;
+ /*
+ * By updating sgm->consumes this will get a proper pointer into the
+ * buffer at any time.
+ */
+ if (!sg_miter_next(sgm)) {
+ /* This shold not happen */
+ dev_err(mmc_dev(host->mmc), "ran out of scatterlist prematurely\n");
+ data->error = -EINVAL;
+ complete(&host->pio_complete);
+ return;
+ }
+ sgp = sgm->addr;
+ remain = sgm->length;
+ if (remain > host->data_len)
+ remain = host->data_len;
if (data->flags & MMC_DATA_WRITE) {
while (remain > 0) {
@@ -331,6 +314,7 @@ static void moxart_transfer_pio(struct moxart_host *host)
sgp++;
len += 4;
}
+ sgm->consumed += len;
remain -= len;
}
@@ -347,22 +331,22 @@ static void moxart_transfer_pio(struct moxart_host *host)
sgp++;
len += 4;
}
+ sgm->consumed += len;
remain -= len;
}
}
- data->bytes_xfered += host->data_remain - remain;
- host->data_remain = remain;
-
- if (host->data_len != data->bytes_xfered)
- moxart_next_sg(host);
- else
+ data->bytes_xfered += sgm->consumed;
+ if (host->data_len == data->bytes_xfered) {
complete(&host->pio_complete);
+ return;
+ }
}
static void moxart_prepare_data(struct moxart_host *host)
{
struct mmc_data *data = host->mrq->cmd->data;
+ unsigned int flags = SG_MITER_ATOMIC; /* Used from IRQ */
u32 datactrl;
int blksz_bits;
@@ -373,15 +357,19 @@ static void moxart_prepare_data(struct moxart_host *host)
blksz_bits = ffs(data->blksz) - 1;
BUG_ON(1 << blksz_bits != data->blksz);
- moxart_init_sg(host, data);
-
datactrl = DCR_DATA_EN | (blksz_bits & DCR_BLK_SIZE);
- if (data->flags & MMC_DATA_WRITE)
+ if (data->flags & MMC_DATA_WRITE) {
+ flags |= SG_MITER_FROM_SG;
datactrl |= DCR_DATA_WRITE;
+ } else {
+ flags |= SG_MITER_TO_SG;
+ }
if (moxart_use_dma(host))
datactrl |= DCR_DMA_EN;
+ else
+ sg_miter_start(&host->sg_miter, data->sg, data->sg_len, flags);
writel(DCR_DATA_FIFO_RESET, host->base + REG_DATA_CONTROL);
writel(MASK_DATA | FIFO_URUN | FIFO_ORUN, host->base + REG_CLEAR);
@@ -454,6 +442,9 @@ static void moxart_request(struct mmc_host *mmc, struct mmc_request *mrq)
}
request_done:
+ if (!moxart_use_dma(host))
+ sg_miter_stop(&host->sg_miter);
+
spin_unlock_irqrestore(&host->lock, flags);
mmc_request_done(host->mmc, mrq);
}
Use the scatterlist memory iterator instead of just dereferencing virtual memory using sg_virt(). This make highmem references work properly. Suggested-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/linux-mmc/20240122073423.GA25859@lst.de/ Signed-off-by: Linus Walleij <linus.walleij@linaro.org> --- drivers/mmc/host/moxart-mmc.c | 77 +++++++++++++++++++------------------------ 1 file changed, 34 insertions(+), 43 deletions(-)