@@ -148,10 +148,8 @@ struct mmc_omap_host {
struct work_struct send_stop_work;
struct mmc_data *stop_data;
+ struct sg_mapping_iter sg_miter;
unsigned int sg_len;
- int sg_idx;
- u16 * buffer;
- u32 buffer_bytes_left;
u32 total_bytes_left;
unsigned features;
@@ -456,6 +454,8 @@ mmc_omap_xfer_done(struct mmc_omap_host *host, struct mmc_data *data)
{
if (host->dma_in_use)
mmc_omap_release_dma(host, data, data->error);
+ else
+ sg_miter_stop(&host->sg_miter);
host->data = NULL;
host->sg_len = 0;
@@ -651,19 +651,6 @@ mmc_omap_cmd_timer(struct timer_list *t)
spin_unlock_irqrestore(&host->slot_lock, flags);
}
-/* PIO only */
-static void
-mmc_omap_sg_to_buf(struct mmc_omap_host *host)
-{
- struct scatterlist *sg;
-
- sg = host->data->sg + host->sg_idx;
- host->buffer_bytes_left = sg->length;
- host->buffer = sg_virt(sg);
- if (host->buffer_bytes_left > host->total_bytes_left)
- host->buffer_bytes_left = host->total_bytes_left;
-}
-
static void
mmc_omap_clk_timer(struct timer_list *t)
{
@@ -676,33 +663,37 @@ mmc_omap_clk_timer(struct timer_list *t)
static void
mmc_omap_xfer_data(struct mmc_omap_host *host, int write)
{
+ struct sg_mapping_iter *sgm = &host->sg_miter;
int n, nwords;
+ u16 *buffer;
- if (host->buffer_bytes_left == 0) {
- host->sg_idx++;
- BUG_ON(host->sg_idx == host->sg_len);
- mmc_omap_sg_to_buf(host);
+ if (!sg_miter_next(sgm)) {
+ /* This should not happen */
+ dev_err(mmc_dev(host->mmc), "ran out of scatterlist prematurely\n");
+ return;
}
+ buffer = sgm->addr;
+
n = 64;
- if (n > host->buffer_bytes_left)
- n = host->buffer_bytes_left;
+ if (n > sgm->length)
+ n = sgm->length;
+ if (n > host->total_bytes_left)
+ n = host->total_bytes_left;
/* Round up to handle odd number of bytes to transfer */
nwords = DIV_ROUND_UP(n, 2);
- host->buffer_bytes_left -= n;
+ sgm->consumed = n;
host->total_bytes_left -= n;
host->data->bytes_xfered += n;
if (write) {
__raw_writesw(host->virt_base + OMAP_MMC_REG(host, DATA),
- host->buffer, nwords);
+ buffer, nwords);
} else {
__raw_readsw(host->virt_base + OMAP_MMC_REG(host, DATA),
- host->buffer, nwords);
+ buffer, nwords);
}
-
- host->buffer += nwords;
}
#ifdef CONFIG_MMC_DEBUG
@@ -956,6 +947,7 @@ static inline void set_data_timeout(struct mmc_omap_host *host, struct mmc_reque
static void
mmc_omap_prepare_data(struct mmc_omap_host *host, struct mmc_request *req)
{
+ unsigned int miter_flags = SG_MITER_ATOMIC; /* Used from IRQ */
struct mmc_data *data = req->data;
int i, use_dma = 1, block_size;
struct scatterlist *sg;
@@ -990,7 +982,6 @@ mmc_omap_prepare_data(struct mmc_omap_host *host, struct mmc_request *req)
}
}
- host->sg_idx = 0;
if (use_dma) {
enum dma_data_direction dma_data_dir;
struct dma_async_tx_descriptor *tx;
@@ -1071,7 +1062,11 @@ mmc_omap_prepare_data(struct mmc_omap_host *host, struct mmc_request *req)
OMAP_MMC_WRITE(host, BUF, 0x1f1f);
host->total_bytes_left = data->blocks * block_size;
host->sg_len = sg_len;
- mmc_omap_sg_to_buf(host);
+ if (data->flags & MMC_DATA_READ)
+ miter_flags |= SG_MITER_TO_SG;
+ else
+ miter_flags |= SG_MITER_FROM_SG;
+ sg_miter_start(&host->sg_miter, data->sg, data->sg_len, miter_flags);
host->dma_in_use = 0;
}
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/omap.c | 53 ++++++++++++++++++++++--------------------------- 1 file changed, 24 insertions(+), 29 deletions(-)