2019-08-28 11:16:58

by Masahiro Yamada

Subject: [PATCH] mmc: sdhci: use lower/upper_32_bits() macros for DMA addresses

Currently, the DMA addresses are casted to (u64) for the upper 32bits
to avoid "right shift count >= width of type" warning.

<linux/kernel.h> provides macros to address this, and the macro names
are self-documenting.

Signed-off-by: Masahiro Yamada <[email protected]>
---

drivers/mmc/host/sdhci.c | 14 ++++++++------
1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index a5dc5aae973e..07144a195a9f 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -668,10 +668,10 @@ void sdhci_adma_write_desc(struct sdhci_host *host, void **desc,
/* 32-bit and 64-bit descriptors have these members in same position */
dma_desc->cmd = cpu_to_le16(cmd);
dma_desc->len = cpu_to_le16(len);
- dma_desc->addr_lo = cpu_to_le32((u32)addr);
+ dma_desc->addr_lo = cpu_to_le32(lower_32_bits(addr));

if (host->flags & SDHCI_USE_64_BIT_DMA)
- dma_desc->addr_hi = cpu_to_le32((u64)addr >> 32);
+ dma_desc->addr_hi = cpu_to_le32(upper_32_bits(addr));

*desc += host->desc_sz;
}
@@ -827,9 +827,10 @@ static dma_addr_t sdhci_sdma_address(struct sdhci_host *host)
static void sdhci_set_sdma_addr(struct sdhci_host *host, dma_addr_t addr)
{
if (host->v4_mode) {
- sdhci_writel(host, addr, SDHCI_ADMA_ADDRESS);
+ sdhci_writel(host, lower_32_bits(addr), SDHCI_ADMA_ADDRESS);
if (host->flags & SDHCI_USE_64_BIT_DMA)
- sdhci_writel(host, (u64)addr >> 32, SDHCI_ADMA_ADDRESS_HI);
+ sdhci_writel(host, upper_32_bits(addr),
+ SDHCI_ADMA_ADDRESS_HI);
} else {
sdhci_writel(host, addr, SDHCI_DMA_ADDRESS);
}
@@ -1096,10 +1097,11 @@ static void sdhci_prepare_data(struct sdhci_host *host, struct mmc_command *cmd)
} else if (host->flags & SDHCI_USE_ADMA) {
sdhci_adma_table_pre(host, data, sg_cnt);

- sdhci_writel(host, host->adma_addr, SDHCI_ADMA_ADDRESS);
+ sdhci_writel(host, lower_32_bits(host->adma_addr),
+ SDHCI_ADMA_ADDRESS);
if (host->flags & SDHCI_USE_64_BIT_DMA)
sdhci_writel(host,
- (u64)host->adma_addr >> 32,
+ upper_32_bits(host->adma_addr),
SDHCI_ADMA_ADDRESS_HI);
} else {
WARN_ON(sg_cnt != 1);
--
2.17.1

2019-08-28 13:04:30

by Adrian Hunter

Subject: Re: [PATCH] mmc: sdhci: use lower/upper_32_bits() macros for DMA addresses

On 28/08/19 2:14 PM, Masahiro Yamada wrote:
> Currently, the DMA addresses are casted to (u64) for the upper 32bits
> to avoid "right shift count >= width of type" warning.
>
> <linux/kernel.h> provides macros to address this, and the macro names
> are self-documenting.
>
> Signed-off-by: Masahiro Yamada <[email protected]>
> ---
>
> drivers/mmc/host/sdhci.c | 14 ++++++++------
> 1 file changed, 8 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
> index a5dc5aae973e..07144a195a9f 100644
> --- a/drivers/mmc/host/sdhci.c
> +++ b/drivers/mmc/host/sdhci.c
> @@ -668,10 +668,10 @@ void sdhci_adma_write_desc(struct sdhci_host *host, void **desc,
> /* 32-bit and 64-bit descriptors have these members in same position */
> dma_desc->cmd = cpu_to_le16(cmd);
> dma_desc->len = cpu_to_le16(len);
> - dma_desc->addr_lo = cpu_to_le32((u32)addr);
> + dma_desc->addr_lo = cpu_to_le32(lower_32_bits(addr));
>
> if (host->flags & SDHCI_USE_64_BIT_DMA)
> - dma_desc->addr_hi = cpu_to_le32((u64)addr >> 32);
> + dma_desc->addr_hi = cpu_to_le32(upper_32_bits(addr));
>
> *desc += host->desc_sz;
> }
> @@ -827,9 +827,10 @@ static dma_addr_t sdhci_sdma_address(struct sdhci_host *host)
> static void sdhci_set_sdma_addr(struct sdhci_host *host, dma_addr_t addr)
> {
> if (host->v4_mode) {

To reduce line wrapping, how about using:

u32 lo = lower_32_bits(addr);
u32 hi = upper_32_bits(addr);

> - sdhci_writel(host, addr, SDHCI_ADMA_ADDRESS);
> + sdhci_writel(host, lower_32_bits(addr), SDHCI_ADMA_ADDRESS);
> if (host->flags & SDHCI_USE_64_BIT_DMA)
> - sdhci_writel(host, (u64)addr >> 32, SDHCI_ADMA_ADDRESS_HI);
> + sdhci_writel(host, upper_32_bits(addr),
> + SDHCI_ADMA_ADDRESS_HI);
> } else {
> sdhci_writel(host, addr, SDHCI_DMA_ADDRESS);
> }
> @@ -1096,10 +1097,11 @@ static void sdhci_prepare_data(struct sdhci_host *host, struct mmc_command *cmd)
> } else if (host->flags & SDHCI_USE_ADMA) {

To reduce line wrapping, how about using:

u32 lo = lower_32_bits(host->adma_addr);
u32 hi = upper_32_bits(host->adma_addr);

> sdhci_adma_table_pre(host, data, sg_cnt);
>
> - sdhci_writel(host, host->adma_addr, SDHCI_ADMA_ADDRESS);
> + sdhci_writel(host, lower_32_bits(host->adma_addr),
> + SDHCI_ADMA_ADDRESS);
> if (host->flags & SDHCI_USE_64_BIT_DMA)
> sdhci_writel(host,
> - (u64)host->adma_addr >> 32,
> + upper_32_bits(host->adma_addr),
> SDHCI_ADMA_ADDRESS_HI);
> } else {
> WARN_ON(sg_cnt != 1);
>

2019-08-29 11:28:02

by Masahiro Yamada

Subject: Re: [PATCH] mmc: sdhci: use lower/upper_32_bits() macros for DMA addresses

Hi.

On Wed, Aug 28, 2019 at 10:02 PM Adrian Hunter <[email protected]> wrote:
>
> On 28/08/19 2:14 PM, Masahiro Yamada wrote:
> > Currently, the DMA addresses are casted to (u64) for the upper 32bits
> > to avoid "right shift count >= width of type" warning.
> >
> > <linux/kernel.h> provides macros to address this, and the macro names
> > are self-documenting.
> >
> > Signed-off-by: Masahiro Yamada <[email protected]>
> > ---
> >
> > drivers/mmc/host/sdhci.c | 14 ++++++++------
> > 1 file changed, 8 insertions(+), 6 deletions(-)
> >
> > diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
> > index a5dc5aae973e..07144a195a9f 100644
> > --- a/drivers/mmc/host/sdhci.c
> > +++ b/drivers/mmc/host/sdhci.c
> > @@ -668,10 +668,10 @@ void sdhci_adma_write_desc(struct sdhci_host *host, void **desc,
> > /* 32-bit and 64-bit descriptors have these members in same position */
> > dma_desc->cmd = cpu_to_le16(cmd);
> > dma_desc->len = cpu_to_le16(len);
> > - dma_desc->addr_lo = cpu_to_le32((u32)addr);
> > + dma_desc->addr_lo = cpu_to_le32(lower_32_bits(addr));
> >
> > if (host->flags & SDHCI_USE_64_BIT_DMA)
> > - dma_desc->addr_hi = cpu_to_le32((u64)addr >> 32);
> > + dma_desc->addr_hi = cpu_to_le32(upper_32_bits(addr));
> >
> > *desc += host->desc_sz;
> > }
> > @@ -827,9 +827,10 @@ static dma_addr_t sdhci_sdma_address(struct sdhci_host *host)
> > static void sdhci_set_sdma_addr(struct sdhci_host *host, dma_addr_t addr)
> > {
> > if (host->v4_mode) {
>
> To reduce line wrapping, how about using:
>
> u32 lo = lower_32_bits(addr);
> u32 hi = upper_32_bits(addr);
>
> > - sdhci_writel(host, addr, SDHCI_ADMA_ADDRESS);
> > + sdhci_writel(host, lower_32_bits(addr), SDHCI_ADMA_ADDRESS);
> > if (host->flags & SDHCI_USE_64_BIT_DMA)
> > - sdhci_writel(host, (u64)addr >> 32, SDHCI_ADMA_ADDRESS_HI);
> > + sdhci_writel(host, upper_32_bits(addr),
> > + SDHCI_ADMA_ADDRESS_HI);
> > } else {
> > sdhci_writel(host, addr, SDHCI_DMA_ADDRESS);
> > }
> > @@ -1096,10 +1097,11 @@ static void sdhci_prepare_data(struct sdhci_host *host, struct mmc_command *cmd)
> > } else if (host->flags & SDHCI_USE_ADMA) {
>
> To reduce line wrapping, how about using:
>
> u32 lo = lower_32_bits(host->adma_addr);
> u32 hi = upper_32_bits(host->adma_addr);
>
> > sdhci_adma_table_pre(host, data, sg_cnt);
> >
> > - sdhci_writel(host, host->adma_addr, SDHCI_ADMA_ADDRESS);
> > + sdhci_writel(host, lower_32_bits(host->adma_addr),
> > + SDHCI_ADMA_ADDRESS);
> > if (host->flags & SDHCI_USE_64_BIT_DMA)
> > sdhci_writel(host,
> > - (u64)host->adma_addr >> 32,
> > + upper_32_bits(host->adma_addr),
> > SDHCI_ADMA_ADDRESS_HI);
> > } else {
> > WARN_ON(sg_cnt != 1);
> >
>


I used another way to reduce the line wrapping in v2.
I factored out the duplicated code into a new helper,
sdhci_set_adma_addr().

If you do not like it, I will adopt your suggestion,
but anyway take a look at v2.

--
Best Regards
Masahiro Yamada