On Mon, Nov 19, 2018 at 02:13:57PM +0100, Wolfram Sang wrote:
> Some variants (namely Renesas SDHI) have bits in the STATS and IRQ_MASK
> registers which are 'always 1' and should be written as such. Introduce
> a seperate mask for this and apply it whenever such a register is
> written.
>
> Signed-off-by: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx>
> ---
>
> This is my response to BSP patches modifying all the register writes directly
> (BSP commits 2d339800bbc73d and f73d5eb86097df). This seems much more future
> proof to me.
>
> Yamada-san: could you check if your HW has 'always 1' bits, too?
>
> Tested on a R-Car M3-N. No regression and no performance impacts when reading
> large files from eMMC or UHS-SD cards.
>
> drivers/mmc/host/renesas_sdhi_core.c | 1 +
> drivers/mmc/host/tmio_mmc.h | 5 +++++
> 2 files changed, 6 insertions(+)
>
> diff --git a/drivers/mmc/host/renesas_sdhi_core.c b/drivers/mmc/host/renesas_sdhi_core.c
> index a049b01206f1..31a351a20dc0 100644
> --- a/drivers/mmc/host/renesas_sdhi_core.c
> +++ b/drivers/mmc/host/renesas_sdhi_core.c
> @@ -722,6 +722,7 @@ int renesas_sdhi_probe(struct platform_device *pdev,
> host->ops.card_busy = renesas_sdhi_card_busy;
> host->ops.start_signal_voltage_switch =
> renesas_sdhi_start_signal_voltage_switch;
> + host->sdcard_irq_setbit_mask = TMIO_STAT_ALWAYS_SET_27;
> }
>
> /* Orginally registers were 16 bit apart, could be 32 or 64 nowadays */
> diff --git a/drivers/mmc/host/tmio_mmc.h b/drivers/mmc/host/tmio_mmc.h
> index 5f6dfb86e43e..c03529e3f01a 100644
> --- a/drivers/mmc/host/tmio_mmc.h
> +++ b/drivers/mmc/host/tmio_mmc.h
> @@ -70,6 +70,7 @@
> #define TMIO_STAT_DAT0 BIT(23) /* only known on R-Car so far */
> #define TMIO_STAT_RXRDY BIT(24)
> #define TMIO_STAT_TXRQ BIT(25)
> +#define TMIO_STAT_ALWAYS_SET_27 BIT(27) /* only known on R-Car 2+ so far */
The _27 seems to be odd to include in the name, but I assume it
was the least bad option you could come up with.
Other that that this looks good to me.
Reviewed-by: Simon Horman <horms+renesas@xxxxxxxxxxxx>
> #define TMIO_STAT_ILL_FUNC BIT(29) /* only when !TMIO_MMC_HAS_IDLE_WAIT */
> #define TMIO_STAT_SCLKDIVEN BIT(29) /* only when TMIO_MMC_HAS_IDLE_WAIT */
> #define TMIO_STAT_CMD_BUSY BIT(30)
> @@ -154,6 +155,7 @@ struct tmio_mmc_host {
> u32 sdcard_irq_mask;
> u32 sdio_irq_mask;
> unsigned int clk_cache;
> + u32 sdcard_irq_setbit_mask;
>
> spinlock_t lock; /* protect host private data */
> unsigned long last_req_ts;
> @@ -268,6 +270,9 @@ static inline void sd_ctrl_write16_rep(struct tmio_mmc_host *host, int addr,
> static inline void sd_ctrl_write32_as_16_and_16(struct tmio_mmc_host *host,
> int addr, u32 val)
> {
> + if (addr == CTL_IRQ_MASK || addr == CTL_STATUS)
> + val |= host->sdcard_irq_setbit_mask;
> +
> iowrite16(val & 0xffff, host->ctl + (addr << host->bus_shift));
> iowrite16(val >> 16, host->ctl + ((addr + 2) << host->bus_shift));
> }
> --
> 2.11.0
>
