[PATCH v2] mmc: sdhci: use lower/upper_32_bits() macros for DMA addresses

From: Masahiro Yamada
Date: Thu Aug 29 2019 - 07:22:43 EST


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 I like the macro
names are self-documenting.

I introduced a new helper, sdhci_set_adma_addr() to avoid the code
duplication.

Signed-off-by: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>
---

Changes in v2:
- Another way to reduce linu wrapping

drivers/mmc/host/sdhci.c | 27 +++++++++++++--------------
1 file changed, 13 insertions(+), 14 deletions(-)

diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 08cc0792c174..66c2cf89ee22 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;
}
@@ -816,6 +816,13 @@ static void sdhci_adma_table_post(struct sdhci_host *host,
}
}

+static void sdhci_set_adma_addr(struct sdhci_host *host, dma_addr_t addr)
+{
+ sdhci_writel(host, lower_32_bits(addr), SDHCI_ADMA_ADDRESS);
+ if (host->flags & SDHCI_USE_64_BIT_DMA)
+ sdhci_writel(host, upper_32_bits(addr), SDHCI_ADMA_ADDRESS_HI);
+}
+
static dma_addr_t sdhci_sdma_address(struct sdhci_host *host)
{
if (host->bounce_buffer)
@@ -826,13 +833,10 @@ 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);
- if (host->flags & SDHCI_USE_64_BIT_DMA)
- sdhci_writel(host, (u64)addr >> 32, SDHCI_ADMA_ADDRESS_HI);
- } else {
+ if (host->v4_mode)
+ sdhci_set_adma_addr(host, addr);
+ else
sdhci_writel(host, addr, SDHCI_DMA_ADDRESS);
- }
}

static unsigned int sdhci_target_timeout(struct sdhci_host *host,
@@ -1095,12 +1099,7 @@ static void sdhci_prepare_data(struct sdhci_host *host, struct mmc_command *cmd)
host->flags &= ~SDHCI_REQ_USE_DMA;
} else if (host->flags & SDHCI_USE_ADMA) {
sdhci_adma_table_pre(host, data, sg_cnt);
-
- sdhci_writel(host, host->adma_addr, SDHCI_ADMA_ADDRESS);
- if (host->flags & SDHCI_USE_64_BIT_DMA)
- sdhci_writel(host,
- (u64)host->adma_addr >> 32,
- SDHCI_ADMA_ADDRESS_HI);
+ sdhci_set_adma_addr(host, host->adma_addr);
} else {
WARN_ON(sg_cnt != 1);
sdhci_set_sdma_addr(host, sdhci_sdma_address(host));
--
2.17.1