Re: [PATCH v2] mmc: sdhci: use lower/upper_32_bits() macros for DMA addresses
From: Ulf Hansson
Date: Thu Aug 29 2019 - 09:34:48 EST
On Thu, 29 Aug 2019 at 13:22, Masahiro Yamada
<yamada.masahiro@xxxxxxxxxxxxx> 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 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>
Applied for next, thanks!
Kind regards
Uffe
> ---
>
> 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
>