From 4f11997773b6b452b5a0d620c5ac5050e75c227e Mon Sep 17 00:00:00 2001 From: Ai Kyuse Date: Thu, 3 Nov 2016 15:16:03 +0100 Subject: [PATCH] mmc: tmio: Add tuning support Add tuning support for use with SDR104 mode Signed-off-by: Ai Kyuse Signed-off-by: Simon Horman Acked-by: Wolfram Sang Tested-by: Wolfram Sang Signed-off-by: Ulf Hansson --- drivers/mmc/host/tmio_mmc.h | 14 ++++++++ drivers/mmc/host/tmio_mmc_pio.c | 62 +++++++++++++++++++++++++++++++++ 2 files changed, 76 insertions(+) diff --git a/drivers/mmc/host/tmio_mmc.h b/drivers/mmc/host/tmio_mmc.h index b8469f2de42b..9e20bcf3aa8d 100644 --- a/drivers/mmc/host/tmio_mmc.h +++ b/drivers/mmc/host/tmio_mmc.h @@ -153,6 +153,7 @@ struct tmio_mmc_host { struct mutex ios_lock; /* protect set_ios() context */ bool native_hotplug; bool sdio_irq_enabled; + u32 scc_tappos; /* Mandatory callback */ int (*clk_enable)(struct tmio_mmc_host *host); @@ -168,6 +169,19 @@ struct tmio_mmc_host { struct mmc_ios *ios); int (*write16_hook)(struct tmio_mmc_host *host, int addr); void (*hw_reset)(struct tmio_mmc_host *host); + void (*prepare_tuning)(struct tmio_mmc_host *host, unsigned long tap); + bool (*check_scc_error)(struct tmio_mmc_host *host); + + /* + * Mandatory callback for tuning to occur which is optional for SDR50 + * and mandatory for SDR104. + */ + unsigned int (*init_tuning)(struct tmio_mmc_host *host); + int (*select_tuning)(struct tmio_mmc_host *host); + + /* Tuning values: 1 for success, 0 for failure */ + DECLARE_BITMAP(taps, BITS_PER_BYTE * sizeof(long)); + unsigned int tap_num; }; struct tmio_mmc_host *tmio_mmc_host_alloc(struct platform_device *pdev); diff --git a/drivers/mmc/host/tmio_mmc_pio.c b/drivers/mmc/host/tmio_mmc_pio.c index 011d04e10231..1b84c635841e 100644 --- a/drivers/mmc/host/tmio_mmc_pio.c +++ b/drivers/mmc/host/tmio_mmc_pio.c @@ -36,6 +36,7 @@ #include #include #include +#include #include #include #include @@ -298,6 +299,9 @@ static void tmio_mmc_finish_request(struct tmio_mmc_host *host) if (mrq->cmd->error || (mrq->data && mrq->data->error)) tmio_mmc_abort_dma(host); + if (host->check_scc_error) + host->check_scc_error(host); + mmc_request_done(host->mmc, mrq); } @@ -797,6 +801,55 @@ static void tmio_mmc_hw_reset(struct mmc_host *mmc) host->hw_reset(host); } +static int tmio_mmc_execute_tuning(struct mmc_host *mmc, u32 opcode) +{ + struct tmio_mmc_host *host = mmc_priv(mmc); + int i, ret = 0; + + if (!host->tap_num) { + if (!host->init_tuning || !host->select_tuning) + /* Tuning is not supported */ + goto out; + + host->tap_num = host->init_tuning(host); + if (!host->tap_num) + /* Tuning is not supported */ + goto out; + } + + if (host->tap_num * 2 >= sizeof(host->taps) * BITS_PER_BYTE) { + dev_warn_once(&host->pdev->dev, + "Too many taps, skipping tuning. Please consider updating size of taps field of tmio_mmc_host\n"); + goto out; + } + + bitmap_zero(host->taps, host->tap_num * 2); + + /* Issue CMD19 twice for each tap */ + for (i = 0; i < 2 * host->tap_num; i++) { + if (host->prepare_tuning) + host->prepare_tuning(host, i % host->tap_num); + + ret = mmc_send_tuning(mmc, opcode, NULL); + if (ret && ret != -EILSEQ) + goto out; + if (ret == 0) + set_bit(i, host->taps); + + mdelay(1); + } + + ret = host->select_tuning(host); + +out: + if (ret < 0) { + dev_warn(&host->pdev->dev, "Tuning procedure failed\n"); + tmio_mmc_hw_reset(mmc); + } + + return ret; +} + /* Process requests from the MMC layer */ static void tmio_mmc_request(struct mmc_host *mmc, struct mmc_request *mrq) { @@ -1014,6 +1067,7 @@ static struct mmc_host_ops tmio_mmc_ops = { .enable_sdio_irq = tmio_mmc_enable_sdio_irq, .multi_io_quirk = tmio_multi_io_quirk, .hw_reset = tmio_mmc_hw_reset, + .execute_tuning = tmio_mmc_execute_tuning, }; static int tmio_mmc_init_ocr(struct tmio_mmc_host *host) @@ -1260,6 +1314,11 @@ int tmio_mmc_host_runtime_suspend(struct device *dev) } EXPORT_SYMBOL(tmio_mmc_host_runtime_suspend); +static bool tmio_mmc_can_retune(struct tmio_mmc_host *host) +{ + return host->tap_num && mmc_can_retune(host->mmc); +} + int tmio_mmc_host_runtime_resume(struct device *dev) { struct mmc_host *mmc = dev_get_drvdata(dev); @@ -1273,6 +1332,9 @@ int tmio_mmc_host_runtime_resume(struct device *dev) tmio_mmc_enable_dma(host, true); + if (tmio_mmc_can_retune(host) && host->select_tuning(host)) + dev_warn(&host->pdev->dev, "Tuning selection failed\n"); + return 0; } EXPORT_SYMBOL(tmio_mmc_host_runtime_resume);