When using DMA, if the DMA addr spans 128MB boundary, we have to split
the DMA transfer into two so that each one doesn't exceed the boundary.
patch1 adds adma_table_num to struct sdhci_host so that driver can
control the ADMA table number.
patch2 introduces adma_write_desc() hook to struct sdhci_ops so that
driver can override it.
patch3 finally solves the 128MB boundary limitation.
Jisheng Zhang (3):
mmc: sdhci: add adma_table_num member to struct sdhci_host
mmc: sdhci: introduce adma_write_desc() hook to struct sdhci_ops
mmc: sdhci-of-dwcmshc: solve 128MB DMA boundary limitation
drivers/mmc/host/sdhci-of-dwcmshc.c | 41 ++++++++++++++++++++++++
drivers/mmc/host/sdhci.c | 48 +++++++++++++++++++----------
drivers/mmc/host/sdhci.h | 8 +++++
3 files changed, 81 insertions(+), 16 deletions(-)
--
2.18.0
This patch adds adma_table_num member to struct sdhci_host to give more
flexibility to drivers to control the ADMA table number.
Default value of adma_table_num is set to (SDHCI_MAX_SEGS * 2 + 1).
Signed-off-by: Jisheng Zhang <[email protected]>
---
drivers/mmc/host/sdhci.c | 17 +++++++++--------
drivers/mmc/host/sdhci.h | 2 ++
2 files changed, 11 insertions(+), 8 deletions(-)
diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index a7b5602ef6f7..14dd4a49e03b 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -3316,6 +3316,13 @@ struct sdhci_host *sdhci_alloc_host(struct device *dev,
host->sdma_boundary = SDHCI_DEFAULT_BOUNDARY_ARG;
+ /*
+ * The DMA descriptor table number is calculated as the maximum
+ * number of segments times 2, to allow for an alignment
+ * descriptor for each segment, plus 1 for a nop end descriptor.
+ */
+ host->adma_table_num = SDHCI_MAX_SEGS * 2 + 1;
+
return host;
}
@@ -3561,18 +3568,12 @@ int sdhci_setup_host(struct sdhci_host *host)
dma_addr_t dma;
void *buf;
- /*
- * The DMA descriptor table size is calculated as the maximum
- * number of segments times 2, to allow for an alignment
- * descriptor for each segment, plus 1 for a nop end descriptor,
- * all multipled by the descriptor size.
- */
if (host->flags & SDHCI_USE_64_BIT_DMA) {
- host->adma_table_sz = (SDHCI_MAX_SEGS * 2 + 1) *
+ host->adma_table_sz = host->adma_table_num *
SDHCI_ADMA2_64_DESC_SZ;
host->desc_sz = SDHCI_ADMA2_64_DESC_SZ;
} else {
- host->adma_table_sz = (SDHCI_MAX_SEGS * 2 + 1) *
+ host->adma_table_sz = host->adma_table_num *
SDHCI_ADMA2_32_DESC_SZ;
host->desc_sz = SDHCI_ADMA2_32_DESC_SZ;
}
diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
index 23966f887da6..d55fd7033e93 100644
--- a/drivers/mmc/host/sdhci.h
+++ b/drivers/mmc/host/sdhci.h
@@ -563,6 +563,8 @@ struct sdhci_host {
/* Host SDMA buffer boundary. */
u32 sdma_boundary;
+ u32 adma_table_num;
+
u64 data_timeout;
unsigned long private[0] ____cacheline_aligned;
--
2.18.0
Add this hook so that it can be overridden with driver specific
implementations. We also rename the original sdhci_adma_write_desc()
to _sdhci_adma_write_desc() and export it, so that it could be reused
by driver's specific implementations.
Signed-off-by: Jisheng Zhang <[email protected]>
---
drivers/mmc/host/sdhci.c | 31 +++++++++++++++++++++++--------
drivers/mmc/host/sdhci.h | 6 ++++++
2 files changed, 29 insertions(+), 8 deletions(-)
diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 14dd4a49e03b..50c846d99182 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -554,8 +554,8 @@ static void sdhci_kunmap_atomic(void *buffer, unsigned long *flags)
local_irq_restore(*flags);
}
-static void sdhci_adma_write_desc(struct sdhci_host *host, void *desc,
- dma_addr_t addr, int len, unsigned cmd)
+unsigned int _sdhci_adma_write_desc(struct sdhci_host *host, void *desc,
+ dma_addr_t addr, int len, unsigned int cmd)
{
struct sdhci_adma2_64_desc *dma_desc = desc;
@@ -566,6 +566,19 @@ static void sdhci_adma_write_desc(struct sdhci_host *host, void *desc,
if (host->flags & SDHCI_USE_64_BIT_DMA)
dma_desc->addr_hi = cpu_to_le32((u64)addr >> 32);
+
+ return host->desc_sz;
+}
+EXPORT_SYMBOL_GPL(_sdhci_adma_write_desc);
+
+static unsigned int sdhci_adma_write_desc(struct sdhci_host *host, void *desc,
+ dma_addr_t addr, int len,
+ unsigned int cmd)
+{
+ if (host->ops->adma_write_desc)
+ return host->ops->adma_write_desc(host, desc, addr, len, cmd);
+
+ return _sdhci_adma_write_desc(host, desc, addr, len, cmd);
}
static void sdhci_adma_mark_end(void *desc)
@@ -585,6 +598,7 @@ static void sdhci_adma_table_pre(struct sdhci_host *host,
void *desc, *align;
char *buffer;
int len, offset, i;
+ unsigned int desc_sz;
/*
* The spec does not specify endianness of descriptor table.
@@ -618,15 +632,16 @@ static void sdhci_adma_table_pre(struct sdhci_host *host,
}
/* tran, valid */
- sdhci_adma_write_desc(host, desc, align_addr, offset,
- ADMA2_TRAN_VALID);
+ desc_sz = sdhci_adma_write_desc(host, desc,
+ align_addr, offset,
+ ADMA2_TRAN_VALID);
BUG_ON(offset > 65536);
align += SDHCI_ADMA2_ALIGN;
align_addr += SDHCI_ADMA2_ALIGN;
- desc += host->desc_sz;
+ desc += desc_sz;
addr += offset;
len -= offset;
@@ -636,9 +651,9 @@ static void sdhci_adma_table_pre(struct sdhci_host *host,
if (len) {
/* tran, valid */
- sdhci_adma_write_desc(host, desc, addr, len,
- ADMA2_TRAN_VALID);
- desc += host->desc_sz;
+ desc_sz = sdhci_adma_write_desc(host, desc, addr, len,
+ ADMA2_TRAN_VALID);
+ desc += desc_sz;
}
/*
diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
index d55fd7033e93..0aad0ee8f63b 100644
--- a/drivers/mmc/host/sdhci.h
+++ b/drivers/mmc/host/sdhci.h
@@ -605,6 +605,9 @@ struct sdhci_ops {
void (*adma_workaround)(struct sdhci_host *host, u32 intmask);
void (*card_event)(struct sdhci_host *host);
void (*voltage_switch)(struct sdhci_host *host);
+ unsigned int (*adma_write_desc)(struct sdhci_host *host, void *desc,
+ dma_addr_t addr, int len,
+ unsigned int cmd);
};
#ifdef CONFIG_MMC_SDHCI_IO_ACCESSORS
@@ -735,6 +738,9 @@ void sdhci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios);
int sdhci_start_signal_voltage_switch(struct mmc_host *mmc,
struct mmc_ios *ios);
void sdhci_enable_sdio_irq(struct mmc_host *mmc, int enable);
+unsigned int _sdhci_adma_write_desc(struct sdhci_host *host, void *desc,
+ dma_addr_t addr, int len,
+ unsigned int cmd);
#ifdef CONFIG_PM
int sdhci_suspend_host(struct sdhci_host *host);
--
2.18.0
When using DMA, if the DMA addr spans 128MB boundary, we have to split
the DMA transfer into two so that each one doesn't exceed the boundary.
Signed-off-by: Jisheng Zhang <[email protected]>
---
drivers/mmc/host/sdhci-of-dwcmshc.c | 41 +++++++++++++++++++++++++++++
1 file changed, 41 insertions(+)
diff --git a/drivers/mmc/host/sdhci-of-dwcmshc.c b/drivers/mmc/host/sdhci-of-dwcmshc.c
index 1b7cd144fb01..01b5cb772554 100644
--- a/drivers/mmc/host/sdhci-of-dwcmshc.c
+++ b/drivers/mmc/host/sdhci-of-dwcmshc.c
@@ -13,16 +13,45 @@
#include "sdhci-pltfm.h"
+#define BOUNDARY_OK(addr, len) \
+ ((addr | (SZ_128M - 1)) == ((addr + len) | (SZ_128M - 1)))
+
struct dwcmshc_priv {
struct clk *bus_clk;
};
+/*
+ * if DMA addr spans 128MB boundary, we split the DMA transfer into two
+ * so that the DMA transfer doesn't exceed the boundary.
+ */
+static unsigned int dwcmshc_adma_write_desc(struct sdhci_host *host,
+ void *desc, dma_addr_t addr,
+ int len, unsigned int cmd)
+{
+ int tmplen, offset;
+
+ if (BOUNDARY_OK(addr, len))
+ return _sdhci_adma_write_desc(host, desc, addr, len, cmd);
+
+ offset = addr & (SZ_128M - 1);
+ tmplen = SZ_128M - offset;
+ _sdhci_adma_write_desc(host, desc, addr, tmplen, cmd);
+
+ addr += tmplen;
+ len -= tmplen;
+ desc += host->desc_sz;
+ _sdhci_adma_write_desc(host, desc, addr, len, cmd);
+
+ return host->desc_sz * 2;
+}
+
static const struct sdhci_ops sdhci_dwcmshc_ops = {
.set_clock = sdhci_set_clock,
.set_bus_width = sdhci_set_bus_width,
.set_uhs_signaling = sdhci_set_uhs_signaling,
.get_max_clock = sdhci_pltfm_clk_get_max_clock,
.reset = sdhci_reset,
+ .adma_write_desc = dwcmshc_adma_write_desc,
};
static const struct sdhci_pltfm_data sdhci_dwcmshc_pdata = {
@@ -36,12 +65,24 @@ static int dwcmshc_probe(struct platform_device *pdev)
struct sdhci_host *host;
struct dwcmshc_priv *priv;
int err;
+ u32 extra;
host = sdhci_pltfm_init(pdev, &sdhci_dwcmshc_pdata,
sizeof(struct dwcmshc_priv));
if (IS_ERR(host))
return PTR_ERR(host);
+ /*
+ * The DMA descriptor table number is calculated as the maximum
+ * number of segments times 2, to allow for an alignment
+ * descriptor for each segment, plus 1 for a nop end descriptor,
+ * plus extra number for cross 128M boundary handling.
+ */
+ extra = totalram_pages / (SZ_128M / PAGE_SIZE) + 1;
+ if (extra > SDHCI_MAX_SEGS)
+ extra = SDHCI_MAX_SEGS;
+ host->adma_table_num = SDHCI_MAX_SEGS * 2 + 1 + extra;
+
pltfm_host = sdhci_priv(host);
priv = sdhci_pltfm_priv(pltfm_host);
--
2.18.0
On Wed, 25 Jul 2018 17:47:49 +0800 Jisheng Zhang wrote:
> When using DMA, if the DMA addr spans 128MB boundary, we have to split
> the DMA transfer into two so that each one doesn't exceed the boundary.
>
> Signed-off-by: Jisheng Zhang <[email protected]>
> ---
> drivers/mmc/host/sdhci-of-dwcmshc.c | 41 +++++++++++++++++++++++++++++
> 1 file changed, 41 insertions(+)
>
> diff --git a/drivers/mmc/host/sdhci-of-dwcmshc.c b/drivers/mmc/host/sdhci-of-dwcmshc.c
> index 1b7cd144fb01..01b5cb772554 100644
> --- a/drivers/mmc/host/sdhci-of-dwcmshc.c
> +++ b/drivers/mmc/host/sdhci-of-dwcmshc.c
> @@ -13,16 +13,45 @@
>
> #include "sdhci-pltfm.h"
>
> +#define BOUNDARY_OK(addr, len) \
> + ((addr | (SZ_128M - 1)) == ((addr + len) | (SZ_128M - 1)))
this should be
((addr | (SZ_128M - 1)) == ((addr + len - 1) | (SZ_128M - 1)))
> +
> struct dwcmshc_priv {
> struct clk *bus_clk;
> };
>
> +/*
> + * if DMA addr spans 128MB boundary, we split the DMA transfer into two
> + * so that the DMA transfer doesn't exceed the boundary.
> + */
> +static unsigned int dwcmshc_adma_write_desc(struct sdhci_host *host,
> + void *desc, dma_addr_t addr,
> + int len, unsigned int cmd)
> +{
> + int tmplen, offset;
> +
> + if (BOUNDARY_OK(addr, len))
> + return _sdhci_adma_write_desc(host, desc, addr, len, cmd);
> +
> + offset = addr & (SZ_128M - 1);
> + tmplen = SZ_128M - offset;
> + _sdhci_adma_write_desc(host, desc, addr, tmplen, cmd);
> +
> + addr += tmplen;
> + len -= tmplen;
> + desc += host->desc_sz;
> + _sdhci_adma_write_desc(host, desc, addr, len, cmd);
> +
> + return host->desc_sz * 2;
> +}
> +
> static const struct sdhci_ops sdhci_dwcmshc_ops = {
> .set_clock = sdhci_set_clock,
> .set_bus_width = sdhci_set_bus_width,
> .set_uhs_signaling = sdhci_set_uhs_signaling,
> .get_max_clock = sdhci_pltfm_clk_get_max_clock,
> .reset = sdhci_reset,
> + .adma_write_desc = dwcmshc_adma_write_desc,
> };
>
> static const struct sdhci_pltfm_data sdhci_dwcmshc_pdata = {
> @@ -36,12 +65,24 @@ static int dwcmshc_probe(struct platform_device *pdev)
> struct sdhci_host *host;
> struct dwcmshc_priv *priv;
> int err;
> + u32 extra;
>
> host = sdhci_pltfm_init(pdev, &sdhci_dwcmshc_pdata,
> sizeof(struct dwcmshc_priv));
> if (IS_ERR(host))
> return PTR_ERR(host);
>
> + /*
> + * The DMA descriptor table number is calculated as the maximum
> + * number of segments times 2, to allow for an alignment
> + * descriptor for each segment, plus 1 for a nop end descriptor,
> + * plus extra number for cross 128M boundary handling.
> + */
> + extra = totalram_pages / (SZ_128M / PAGE_SIZE) + 1;
will use DIV_ROUND_UP instead.
> + if (extra > SDHCI_MAX_SEGS)
> + extra = SDHCI_MAX_SEGS;
> + host->adma_table_num = SDHCI_MAX_SEGS * 2 + 1 + extra;
> +
> pltfm_host = sdhci_priv(host);
> priv = sdhci_pltfm_priv(pltfm_host);
>