github-mirror/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-05-24 07:03:03 +02:00
Code Issues Actions Packages Projects Releases Wiki Activity Graph

mmc: omap: Use sg_miter for PIO

Browse Source 
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>
Link: https://lore.kernel.org/r/20240127-mmc-proper-kmap-v2-7-d8e732aa97d1@linaro.org
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
This commit is contained in:
Linus Walleij 2024-01-27 01:19:54 +01:00 committed by Ulf Hansson
parent 12658af54f
commit 68cfdeb406
1 changed files with 24 additions and 29 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

53
drivers/mmc/host/omap.c
View File

@ -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;
}