Re: [PATCH 2/3] [2/3] mmc: mediatek: command queue support
From: Ulf Hansson
Date: Mon Nov 11 2019 - 08:38:33 EST
+ Trimmed cc list (please do that as well for your next submission).
On Fri, 1 Nov 2019 at 07:43, Chun-Hung Wu <chun-hung.wu@xxxxxxxxxxxx> wrote:
>
> Support command queue for mt6779 platform.
A lot of changes summarized on only one line. I would appreciate some
more information here, please.
>
> Change-Id: I56b866fa4097a3c0bee77f53486c470e4f1944b9
> Feature:
Drop these please.
> Signed-off-by: Chun-Hung Wu <chun-hung.wu@xxxxxxxxxxxx>
For the next submission, please add the maintainers for the cqhci
driver. They may have some valuable feedback for you.
Below follows a few review comments, which are more from a patch
formatting point of view, than technical.
> ---
> drivers/mmc/host/mtk-sd.c | 151 +++++++++++++++++++++++++++++++++++++++++++---
> 1 file changed, 141 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/mmc/host/mtk-sd.c b/drivers/mmc/host/mtk-sd.c
> index 189e426..b132397 100644
> --- a/drivers/mmc/host/mtk-sd.c
> +++ b/drivers/mmc/host/mtk-sd.c
> @@ -31,6 +31,8 @@
> #include <linux/mmc/sdio.h>
> #include <linux/mmc/slot-gpio.h>
>
> +#include "cqhci.h"
> +
> #define MAX_BD_NUM 1024
>
> /*--------------------------------------------------------------------------*/
> @@ -151,6 +153,7 @@
> #define MSDC_INT_DMA_BDCSERR (0x1 << 17) /* W1C */
> #define MSDC_INT_DMA_GPDCSERR (0x1 << 18) /* W1C */
> #define MSDC_INT_DMA_PROTECT (0x1 << 19) /* W1C */
> +#define MSDC_INT_CMDQ (0x1 << 28) /* W1C */
>
> /* MSDC_INTEN mask */
> #define MSDC_INTEN_MMCIRQ (0x1 << 0) /* RW */
> @@ -181,6 +184,7 @@
> /* SDC_CFG mask */
> #define SDC_CFG_SDIOINTWKUP (0x1 << 0) /* RW */
> #define SDC_CFG_INSWKUP (0x1 << 1) /* RW */
> +#define SDC_CFG_WRDTOC (0x1fff << 2) /* RW */
> #define SDC_CFG_BUSWIDTH (0x3 << 16) /* RW */
> #define SDC_CFG_SDIO (0x1 << 19) /* RW */
> #define SDC_CFG_SDIOIDE (0x1 << 20) /* RW */
> @@ -228,6 +232,7 @@
> #define MSDC_PATCH_BIT_SPCPUSH (0x1 << 29) /* RW */
> #define MSDC_PATCH_BIT_DECRCTMO (0x1 << 30) /* RW */
>
> +#define MSDC_PB1_BUSY_CHECK_SEL (0x1 << 7) /* RW */
> #define MSDC_PATCH_BIT1_STOP_DLY (0xf << 8) /* RW */
>
> #define MSDC_PATCH_BIT2_CFGRESP (0x1 << 15) /* RW */
> @@ -431,6 +436,7 @@ struct msdc_host {
> struct msdc_save_para save_para; /* used when gate HCLK */
> struct msdc_tune_para def_tune_para; /* default tune setting */
> struct msdc_tune_para saved_tune_para; /* tune result of CMD21/CMD19 */
> + struct cqhci_host *cq_host;
> };
>
> static const struct mtk_mmc_compatible mt8135_compat = {
> @@ -527,6 +533,18 @@ struct msdc_host {
> .use_internal_cd = true,
> };
>
> +static const struct mtk_mmc_compatible mt6779_compat = {
> + .clk_div_bits = 12,
> + .hs400_tune = false,
> + .pad_tune_reg = MSDC_PAD_TUNE0,
> + .async_fifo = true,
> + .data_tune = true,
> + .busy_check = true,
> + .stop_clk_fix = true,
> + .enhance_rx = true,
> + .support_64g = true,
> +};
> +
> static const struct of_device_id msdc_of_ids[] = {
> { .compatible = "mediatek,mt8135-mmc", .data = &mt8135_compat},
> { .compatible = "mediatek,mt8173-mmc", .data = &mt8173_compat},
> @@ -536,6 +554,7 @@ struct msdc_host {
> { .compatible = "mediatek,mt7622-mmc", .data = &mt7622_compat},
> { .compatible = "mediatek,mt8516-mmc", .data = &mt8516_compat},
> { .compatible = "mediatek,mt7620-mmc", .data = &mt7620_compat},
> + { .compatible = "mediatek,mt6779-mmc", .data = &mt6779_compat},
> {}
> };
> MODULE_DEVICE_TABLE(of, msdc_of_ids);
> @@ -698,21 +717,21 @@ static void msdc_unprepare_data(struct msdc_host *host, struct mmc_request *mrq)
> }
> }
>
> -/* clock control primitives */
> -static void msdc_set_timeout(struct msdc_host *host, u32 ns, u32 clks)
> +static u64 msdc_timeout_cal(struct msdc_host *host, u64 ns, u64 clks)
> {
> - u32 timeout, clk_ns;
> + u64 timeout, clk_ns;
> u32 mode = 0;
>
> - host->timeout_ns = ns;
> - host->timeout_clks = clks;
> if (host->mmc->actual_clock == 0) {
> timeout = 0;
> } else {
> - clk_ns = 1000000000UL / host->mmc->actual_clock;
> - timeout = (ns + clk_ns - 1) / clk_ns + clks;
> + clk_ns = 1000000000ULL;
> + do_div(clk_ns, host->mmc->actual_clock);
> + timeout = ns + clk_ns - 1;
> + do_div(timeout, clk_ns);
> + timeout += clks;
> /* in 1048576 sclk cycle unit */
> - timeout = (timeout + (0x1 << 20) - 1) >> 20;
> + timeout = DIV_ROUND_UP(timeout, (0x1 << 20));
> if (host->dev_comp->clk_div_bits == 8)
> sdr_get_field(host->base + MSDC_CFG,
> MSDC_CFG_CKMOD, &mode);
> @@ -722,9 +741,30 @@ static void msdc_set_timeout(struct msdc_host *host, u32 ns, u32 clks)
> /*DDR mode will double the clk cycles for data timeout */
> timeout = mode >= 2 ? timeout * 2 : timeout;
> timeout = timeout > 1 ? timeout - 1 : 0;
> - timeout = timeout > 255 ? 255 : timeout;
> }
> - sdr_set_field(host->base + SDC_CFG, SDC_CFG_DTOC, timeout);
> + return timeout;
> +}
> +
> +/* clock control primitives */
> +static void msdc_set_timeout(struct msdc_host *host, u64 ns, u64 clks)
> +{
> + u64 timeout;
> +
> + host->timeout_ns = ns;
> + host->timeout_clks = clks;
> +
> + timeout = msdc_timeout_cal(host, ns, clks);
> + sdr_set_field(host->base + SDC_CFG, SDC_CFG_DTOC,
> + (u32)(timeout > 255 ? 255 : timeout));
> +}
Does the above changes make sense to split out in a separate patch?
It looks to me, that these are generic clock updates to the driver
that really doesn't have to be included in $subject patch.
> +
> +static void msdc_set_busy_timeout(struct msdc_host *host, u64 ns, u64 clks)
> +{
> + u64 timeout;
> +
> + timeout = msdc_timeout_cal(host, ns, clks);
> + sdr_set_field(host->base + SDC_CFG, SDC_CFG_WRDTOC,
> + (u32)(timeout > 8191 ? 8191 : timeout));
> }
>
> static void msdc_gate_clock(struct msdc_host *host)
> @@ -1413,6 +1453,36 @@ static void msdc_enable_sdio_irq(struct mmc_host *mmc, int enb)
> pm_runtime_put_noidle(host->dev);
> }
>
> +#if IS_ENABLED(CONFIG_MMC_CQHCI)
Other drivers Kconfig option, uses "select MMC_CQHCI". Would that make
this more simple and allowing to remove the "if IS_ENABLED" thingy?
> +static irqreturn_t msdc_cmdq_irq(struct msdc_host *host, u32 intsts)
> +{
> + int cmd_err = 0, dat_err = 0;
> +
> + if (intsts & MSDC_INT_RSPCRCERR) {
> + cmd_err = (unsigned int)-EILSEQ;
> + dev_err(host->dev, "%s: CMD CRC ERR", __func__);
> + } else if (intsts & MSDC_INT_CMDTMO) {
> + cmd_err = (unsigned int)-ETIMEDOUT;
> + dev_err(host->dev, "%s: CMD TIMEOUT ERR", __func__);
> + }
> +
> + if (intsts & MSDC_INT_DATCRCERR) {
> + dat_err = (unsigned int)-EILSEQ;
> + dev_err(host->dev, "%s: DATA CRC ERR", __func__);
> + } else if (intsts & MSDC_INT_DATTMO) {
> + dat_err = (unsigned int)-ETIMEDOUT;
> + dev_err(host->dev, "%s: DATA TIMEOUT ERR", __func__);
> + }
> +
> + if (cmd_err || dat_err) {
> + dev_err(host->dev, "cmd_err = %d, dat_err =%d, intsts = 0x%x",
> + cmd_err, dat_err, intsts);
> + }
> +
> + return cqhci_irq(host->mmc, 0, cmd_err, dat_err);
> +}
> +#endif
> +
> static irqreturn_t msdc_irq(int irq, void *dev_id)
> {
> struct msdc_host *host = (struct msdc_host *) dev_id;
> @@ -1449,6 +1519,16 @@ static irqreturn_t msdc_irq(int irq, void *dev_id)
> if (!(events & (event_mask & ~MSDC_INT_SDIOIRQ)))
> break;
>
> +#if IS_ENABLED(CONFIG_MMC_CQHCI)
Again, please to avoid these "IS_ENABLED".
> + if ((host->mmc->caps2 & MMC_CAP2_CQE) &&
> + (events & MSDC_INT_CMDQ)) {
> + msdc_cmdq_irq(host, events);
> + /* clear interrupts */
> + writel(events, host->base + MSDC_INT);
> + return IRQ_HANDLED;
> + }
> +#endif
> +
> if (!mrq) {
> dev_err(host->dev,
> "%s: MRQ=NULL; events=%08X; event_mask=%08X\n",
> @@ -2132,6 +2212,36 @@ static int msdc_get_cd(struct mmc_host *mmc)
> return !val;
> }
>
> +static void msdc_cqe_enable(struct mmc_host *mmc)
> +{
> + struct msdc_host *host = mmc_priv(mmc);
> +
> + /* enable cmdq irq */
> + writel(MSDC_INT_CMDQ, host->base + MSDC_INTEN);
> + /* enable busy check */
> + sdr_set_bits(host->base + MSDC_PATCH_BIT1, MSDC_PB1_BUSY_CHECK_SEL);
> + /* default write data / busy timeout 20s */
> + msdc_set_busy_timeout(host, 20 * 1000000000ULL, 0);
> + /* default read data timeout 1s */
> + msdc_set_timeout(host, 1000000000ULL, 0);
Some magic timeout values here. Can you elaborate why these values?
> +}
> +
> +void msdc_cqe_disable(struct mmc_host *mmc, bool recovery)
> +{
> + struct msdc_host *host = mmc_priv(mmc);
> +
> + /* disable cmdq irq */
> + sdr_clr_bits(host->base + MSDC_INTEN, MSDC_INT_CMDQ);
> + /* disable busy check */
> + sdr_clr_bits(host->base + MSDC_PATCH_BIT1, MSDC_PB1_BUSY_CHECK_SEL);
> +
> + if (recovery) {
> + sdr_set_field(host->base + MSDC_DMA_CTRL,
> + MSDC_DMA_CTRL_STOP, 1);
> + msdc_reset_hw(host);
> + }
> +}
> +
> static const struct mmc_host_ops mt_msdc_ops = {
> .post_req = msdc_post_req,
> .pre_req = msdc_pre_req,
> @@ -2148,6 +2258,11 @@ static int msdc_get_cd(struct mmc_host *mmc)
> .hw_reset = msdc_hw_reset,
The hw_reset callback is really for resetting the card, but it seems
like you are using it to reset the controller. No?
I notice there are some other drivers abusing the callback as well,
but I am wondering whether it's time to really look into what's going
on here.
Can you elaborate on why you need this?
> };
>
> +static const struct cqhci_host_ops msdc_cmdq_ops = {
> + .enable = msdc_cqe_enable,
> + .disable = msdc_cqe_disable,
> +};
> +
> static void msdc_of_property_parse(struct platform_device *pdev,
> struct msdc_host *host)
> {
> @@ -2299,6 +2414,22 @@ static int msdc_drv_probe(struct platform_device *pdev)
> host->dma_mask = DMA_BIT_MASK(32);
> mmc_dev(mmc)->dma_mask = &host->dma_mask;
>
> +#if IS_ENABLED(CONFIG_MMC_CQHCI)
> + if (mmc->caps2 & MMC_CAP2_CQE) {
> + host->cq_host = devm_kzalloc(host->mmc->parent,
> + sizeof(*host->cq_host),
> + GFP_KERNEL);
> + host->cq_host->caps |= CQHCI_TASK_DESC_SZ_128;
> + host->cq_host->mmio = host->base + 0x800;
> + host->cq_host->ops = &msdc_cmdq_ops;
> + cqhci_init(host->cq_host, mmc, true);
> + mmc->max_segs = 128;
> + /* cqhci 16bit length */
> + /* 0 size, means 65536 so we don't have to -1 here */
> + mmc->max_seg_size = 64 * 1024;
> + }
> +#endif
> +
> host->timeout_clks = 3 * 1048576;
> host->dma.gpd = dma_alloc_coherent(&pdev->dev,
> 2 * sizeof(struct mt_gpdma_desc),
> --
> 1.9.1
>
Kind regards
Uffe