Am 15.02.2017 um 18:04 schrieb Kevin Hilman:
> Heiner Kallweit <hkallweit1@xxxxxxxxx> writes:
>
>> Remove use of unneeded members cmd_arg and cmd_resp.
>> Setting SD_EMMC_CMD_RSP is only needed if CMD_CFG_RESP_NUM is set,
>> so don't write this register in all other cases.
>>
>> Signed-off-by: Heiner Kallweit <hkallweit1@xxxxxxxxx>
>
> I'm not sure I like this change. This works now because there is only
> one descriptor used, but one of the next things to work on in this
> driver is taking advantage of the internal DMA capabilities, which means
> having a chain of descriptorsall filled out in memory.
>
I implemented the descriptor chain mode and tests (together with CMD23
mode) resulted in 140 MB/s read performance (from a 128GB eMMC card).
So I will submit this extension together with the CMD23 mode extension.
Heiner
> Kevin
>
>> ---
>> drivers/mmc/host/meson-gx-mmc.c | 6 ++----
>> 1 file changed, 2 insertions(+), 4 deletions(-)
>>
>> diff --git a/drivers/mmc/host/meson-gx-mmc.c b/drivers/mmc/host/meson-gx-mmc.c
>> index ece38b44..630e0590 100644
>> --- a/drivers/mmc/host/meson-gx-mmc.c
>> +++ b/drivers/mmc/host/meson-gx-mmc.c
>> @@ -456,7 +456,6 @@ static void meson_mmc_start_cmd(struct mmc_host *mmc, struct mmc_command *cmd)
>> desc->cmd_cfg |= (cmd->opcode & CMD_CFG_CMD_INDEX_MASK) <<
>> CMD_CFG_CMD_INDEX_SHIFT;
>> desc->cmd_cfg |= CMD_CFG_OWNER; /* owned by CPU */
>> - desc->cmd_arg = cmd->arg;
>>
>> /* Response */
>> if (cmd->flags & MMC_RSP_PRESENT) {
>> @@ -464,7 +463,7 @@ static void meson_mmc_start_cmd(struct mmc_host *mmc, struct mmc_command *cmd)
>> if (cmd->flags & MMC_RSP_136)
>> desc->cmd_cfg |= CMD_CFG_RESP_128;
>> desc->cmd_cfg |= CMD_CFG_RESP_NUM;
>> - desc->cmd_resp = 0;
>> + writel(0, host->regs + SD_EMMC_CMD_RSP);
>>
>> if (!(cmd->flags & MMC_RSP_CRC))
>> desc->cmd_cfg |= CMD_CFG_RESP_NOCRC;
>> @@ -540,9 +539,8 @@ static void meson_mmc_start_cmd(struct mmc_host *mmc, struct mmc_command *cmd)
>> desc->cmd_cfg |= CMD_CFG_END_OF_CHAIN;
>> writel(desc->cmd_cfg, host->regs + SD_EMMC_CMD_CFG);
>> writel(desc->cmd_data, host->regs + SD_EMMC_CMD_DAT);
>> - writel(desc->cmd_resp, host->regs + SD_EMMC_CMD_RSP);
>> wmb(); /* ensure descriptor is written before kicked */
>> - writel(desc->cmd_arg, host->regs + SD_EMMC_CMD_ARG);
>> + writel(cmd->arg, host->regs + SD_EMMC_CMD_ARG);
>> }
>>
>> static void meson_mmc_request(struct mmc_host *mmc, struct mmc_request *mrq)
>
--
To unsubscribe from this list: send the line "unsubscribe linux-mmc" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
