Re: [PATCH v4 2/3] sdhci: sparx5: Add Sparx5 SoC eMMC driver

Adrian Hunter
2020-08-24T15:52:31Z

On 24/08/20 6:10 pm, Lars Povlsen wrote:
> This adds the eMMC driver for the Sparx5 SoC. It is based upon the
> designware IP, but requires some extra initialization and quirks.
>
> Signed-off-by: Lars Povlsen <lars.povlsen@microchip.com>

Already acked this, still:

Acked-by: Adrian Hunter <adrian.hunter@intel.com>

> ---
> drivers/mmc/host/Kconfig | 13 ++
> drivers/mmc/host/Makefile | 1 +
> drivers/mmc/host/sdhci-of-sparx5.c | 269 +++++++++++++++++++++++++++++
> 3 files changed, 283 insertions(+)
> create mode 100644 drivers/mmc/host/sdhci-of-sparx5.c
>
> diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig
> index 3b706af35ec31..a3bad4b4ed7ea 100644
> --- a/drivers/mmc/host/Kconfig
> +++ b/drivers/mmc/host/Kconfig
> @@ -213,6 +213,19 @@ config MMC_SDHCI_OF_DWCMSHC
> If you have a controller with this interface, say Y or M here.
> If unsure, say N.
>
> +config MMC_SDHCI_OF_SPARX5
> + tristate "SDHCI OF support for the MCHP Sparx5 SoC"
> + depends on MMC_SDHCI_PLTFM
> + depends on ARCH_SPARX5
> + select MMC_SDHCI_IO_ACCESSORS
> + help
> + This selects the Secure Digital Host Controller Interface (SDHCI)
> + found in the MCHP Sparx5 SoC.
> +
> + If you have a Sparx5 SoC with this interface, say Y or M here.
> +
> + If unsure, say N.
> +
> config MMC_SDHCI_CADENCE
> tristate "SDHCI support for the Cadence SD/SDIO/eMMC controller"
> depends on MMC_SDHCI_PLTFM
> diff --git a/drivers/mmc/host/Makefile b/drivers/mmc/host/Makefile
> index 4d5bcb0144a0a..451c25fc2c692 100644
> --- a/drivers/mmc/host/Makefile
> +++ b/drivers/mmc/host/Makefile
> @@ -94,6 +94,7 @@ obj-$(CONFIG_MMC_SDHCI_OF_AT91) += sdhci-of-at91.o
> obj-$(CONFIG_MMC_SDHCI_OF_ESDHC) += sdhci-of-esdhc.o
> obj-$(CONFIG_MMC_SDHCI_OF_HLWD) += sdhci-of-hlwd.o
> obj-$(CONFIG_MMC_SDHCI_OF_DWCMSHC) += sdhci-of-dwcmshc.o
> +obj-$(CONFIG_MMC_SDHCI_OF_SPARX5) += sdhci-of-sparx5.o
> obj-$(CONFIG_MMC_SDHCI_BCM_KONA) += sdhci-bcm-kona.o
> obj-$(CONFIG_MMC_SDHCI_IPROC) += sdhci-iproc.o
> obj-$(CONFIG_MMC_SDHCI_MSM) += sdhci-msm.o
> diff --git a/drivers/mmc/host/sdhci-of-sparx5.c b/drivers/mmc/host/sdhci-of-sparx5.c
> new file mode 100644
> index 0000000000000..2b262c12e5530
> --- /dev/null
> +++ b/drivers/mmc/host/sdhci-of-sparx5.c
> @@ -0,0 +1,269 @@
> +// SPDX-License-Identifier: GPL-2.0-or-later
> +/*
> + * drivers/mmc/host/sdhci-of-sparx5.c
> + *
> + * MCHP Sparx5 SoC Secure Digital Host Controller Interface.
> + *
> + * Copyright (c) 2019 Microchip Inc.
> + *
> + * Author: Lars Povlsen <lars.povlsen@microchip.com>
> + */
> +
> +#include <linux/sizes.h>
> +#include <linux/delay.h>
> +#include <linux/module.h>
> +#include <linux/regmap.h>
> +#include <linux/of_device.h>
> +#include <linux/mfd/syscon.h>
> +#include <linux/dma-mapping.h>
> +
> +#include "sdhci-pltfm.h"
> +
> +#define CPU_REGS_GENERAL_CTRL (0x22 * 4)
> +#define MSHC_DLY_CC_MASK GENMASK(16, 13)
> +#define MSHC_DLY_CC_SHIFT 13
> +#define MSHC_DLY_CC_MAX 15
> +
> +#define CPU_REGS_PROC_CTRL (0x2C * 4)
> +#define ACP_CACHE_FORCE_ENA BIT(4)
> +#define ACP_AWCACHE BIT(3)
> +#define ACP_ARCACHE BIT(2)
> +#define ACP_CACHE_MASK (ACP_CACHE_FORCE_ENA|ACP_AWCACHE|ACP_ARCACHE)
> +
> +#define MSHC2_VERSION 0x500 /* Off 0x140, reg 0x0 */
> +#define MSHC2_TYPE 0x504 /* Off 0x140, reg 0x1 */
> +#define MSHC2_EMMC_CTRL 0x52c /* Off 0x140, reg 0xB */
> +#define MSHC2_EMMC_CTRL_EMMC_RST_N BIT(2)
> +#define MSHC2_EMMC_CTRL_IS_EMMC BIT(0)
> +
> +struct sdhci_sparx5_data {
> + struct sdhci_host *host;
> + struct regmap *cpu_ctrl;
> + int delay_clock;
> +};
> +
> +#define BOUNDARY_OK(addr, len) \
> + ((addr | (SZ_128M - 1)) == ((addr + len - 1) | (SZ_128M - 1)))
> +
> +/*
> + * If DMA addr spans 128MB boundary, we split the DMA transfer into two
> + * so that each DMA transfer doesn't exceed the boundary.
> + */
> +static void sdhci_sparx5_adma_write_desc(struct sdhci_host *host, void **desc,
> + dma_addr_t addr, int len,
> + unsigned int cmd)
> +{
> + int tmplen, offset;
> +
> + if (likely(!len || BOUNDARY_OK(addr, len))) {
> + sdhci_adma_write_desc(host, desc, addr, len, cmd);
> + return;
> + }
> +
> + pr_debug("%s: write_desc: splitting dma len %d, offset 0x%0llx\n",
> + mmc_hostname(host->mmc), len, addr);
> +
> + offset = addr & (SZ_128M - 1);
> + tmplen = SZ_128M - offset;
> + sdhci_adma_write_desc(host, desc, addr, tmplen, cmd);
> +
> + addr += tmplen;
> + len -= tmplen;
> + sdhci_adma_write_desc(host, desc, addr, len, cmd);
> +}
> +
> +static void sparx5_set_cacheable(struct sdhci_host *host, u32 value)
> +{
> + struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
> + struct sdhci_sparx5_data *sdhci_sparx5 = sdhci_pltfm_priv(pltfm_host);
> +
> + pr_debug("%s: Set Cacheable = 0x%x\n", mmc_hostname(host->mmc), value);
> +
> + /* Update ACP caching attributes in HW */
> + regmap_update_bits(sdhci_sparx5->cpu_ctrl,
> + CPU_REGS_PROC_CTRL, ACP_CACHE_MASK, value);
> +}
> +
> +static void sparx5_set_delay(struct sdhci_host *host, u8 value)
> +{
> + struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
> + struct sdhci_sparx5_data *sdhci_sparx5 = sdhci_pltfm_priv(pltfm_host);
> +
> + pr_debug("%s: Set DLY_CC = %u\n", mmc_hostname(host->mmc), value);
> +
> + /* Update DLY_CC in HW */
> + regmap_update_bits(sdhci_sparx5->cpu_ctrl,
> + CPU_REGS_GENERAL_CTRL,
> + MSHC_DLY_CC_MASK,
> + (value << MSHC_DLY_CC_SHIFT));
> +}
> +
> +static void sdhci_sparx5_set_emmc(struct sdhci_host *host)
> +{
> + if (!mmc_card_is_removable(host->mmc)) {
> + u8 value;
> +
> + value = sdhci_readb(host, MSHC2_EMMC_CTRL);
> + if (!(value & MSHC2_EMMC_CTRL_IS_EMMC)) {
> + value |= MSHC2_EMMC_CTRL_IS_EMMC;
> + pr_debug("%s: Set EMMC_CTRL: 0x%08x\n",
> + mmc_hostname(host->mmc), value);
> + sdhci_writeb(host, value, MSHC2_EMMC_CTRL);
> + }
> + }
> +}
> +
> +static void sdhci_sparx5_reset_emmc(struct sdhci_host *host)
> +{
> + u8 value;
> +
> + pr_debug("%s: Toggle EMMC_CTRL.EMMC_RST_N\n", mmc_hostname(host->mmc));
> + value = sdhci_readb(host, MSHC2_EMMC_CTRL) &
> + ~MSHC2_EMMC_CTRL_EMMC_RST_N;
> + sdhci_writeb(host, value, MSHC2_EMMC_CTRL);
> + /* For eMMC, minimum is 1us but give it 10us for good measure */
> + usleep_range(10, 20);
> + sdhci_writeb(host, value | MSHC2_EMMC_CTRL_EMMC_RST_N,
> + MSHC2_EMMC_CTRL);
> + /* For eMMC, minimum is 200us but give it 300us for good measure */
> + usleep_range(300, 400);
> +}
> +
> +static void sdhci_sparx5_reset(struct sdhci_host *host, u8 mask)
> +{
> + pr_debug("%s: *** RESET: mask %d\n", mmc_hostname(host->mmc), mask);
> +
> + sdhci_reset(host, mask);
> +
> + /* Be sure CARD_IS_EMMC stays set */
> + sdhci_sparx5_set_emmc(host);
> +}
> +
> +static const struct sdhci_ops sdhci_sparx5_ops = {
> + .set_clock = sdhci_set_clock,
> + .set_bus_width = sdhci_set_bus_width,
> + .set_uhs_signaling = sdhci_set_uhs_signaling,
> + .get_max_clock = sdhci_pltfm_clk_get_max_clock,
> + .reset = sdhci_sparx5_reset,
> + .adma_write_desc = sdhci_sparx5_adma_write_desc,
> +};
> +
> +static const struct sdhci_pltfm_data sdhci_sparx5_pdata = {
> + .quirks = 0,
> + .quirks2 = SDHCI_QUIRK2_HOST_NO_CMD23 | /* Controller issue */
> + SDHCI_QUIRK2_NO_1_8_V, /* No sdr104, ddr50, etc */
> + .ops = &sdhci_sparx5_ops,
> +};
> +
> +int sdhci_sparx5_probe(struct platform_device *pdev)
> +{
> + int ret;
> + const char *syscon = "microchip,sparx5-cpu-syscon";
> + struct sdhci_host *host;
> + struct sdhci_pltfm_host *pltfm_host;
> + struct sdhci_sparx5_data *sdhci_sparx5;
> + struct device_node *np = pdev->dev.of_node;
> + u32 value;
> + u32 extra;
> +
> + host = sdhci_pltfm_init(pdev, &sdhci_sparx5_pdata,
> + sizeof(*sdhci_sparx5));
> +
> + if (IS_ERR(host))
> + return PTR_ERR(host);
> +
> + /*
> + * extra adma table cnt for cross 128M boundary handling.
> + */
> + extra = DIV_ROUND_UP_ULL(dma_get_required_mask(&pdev->dev), SZ_128M);
> + if (extra > SDHCI_MAX_SEGS)
> + extra = SDHCI_MAX_SEGS;
> + host->adma_table_cnt += extra;
> +
> + pltfm_host = sdhci_priv(host);
> + sdhci_sparx5 = sdhci_pltfm_priv(pltfm_host);
> + sdhci_sparx5->host = host;
> +
> + pltfm_host->clk = devm_clk_get(&pdev->dev, "core");
> + if (IS_ERR(pltfm_host->clk)) {
> + ret = PTR_ERR(pltfm_host->clk);
> + dev_err(&pdev->dev, "failed to get core clk: %d\n", ret);
> + goto free_pltfm;
> + }
> + ret = clk_prepare_enable(pltfm_host->clk);
> + if (ret)
> + goto free_pltfm;
> +
> + if (!of_property_read_u32(np, "microchip,clock-delay", &value) &&
> + (value > 0 && value <= MSHC_DLY_CC_MAX))
> + sdhci_sparx5->delay_clock = value;
> +
> + sdhci_get_of_property(pdev);
> +
> + ret = mmc_of_parse(host->mmc);
> + if (ret)
> + goto err_clk;
> +
> + sdhci_sparx5->cpu_ctrl = syscon_regmap_lookup_by_compatible(syscon);
> + if (IS_ERR(sdhci_sparx5->cpu_ctrl)) {
> + dev_err(&pdev->dev, "No CPU syscon regmap !\n");
> + ret = PTR_ERR(sdhci_sparx5->cpu_ctrl);
> + goto err_clk;
> + }
> +
> + if (sdhci_sparx5->delay_clock >= 0)
> + sparx5_set_delay(host, sdhci_sparx5->delay_clock);
> +
> + if (!mmc_card_is_removable(host->mmc)) {
> + /* Do a HW reset of eMMC card */
> + sdhci_sparx5_reset_emmc(host);
> + /* Update EMMC_CTRL */
> + sdhci_sparx5_set_emmc(host);
> + /* If eMMC, disable SD and SDIO */
> + host->mmc->caps2 |= (MMC_CAP2_NO_SDIO|MMC_CAP2_NO_SD);
> + }
> +
> + ret = sdhci_add_host(host);
> + if (ret)
> + goto err_clk;
> +
> + /* Set AXI bus master to use un-cached access (for DMA) */
> + if (host->flags & (SDHCI_USE_SDMA | SDHCI_USE_ADMA) &&
> + IS_ENABLED(CONFIG_DMA_DECLARE_COHERENT))
> + sparx5_set_cacheable(host, ACP_CACHE_FORCE_ENA);
> +
> + pr_debug("%s: SDHC version: 0x%08x\n",
> + mmc_hostname(host->mmc), sdhci_readl(host, MSHC2_VERSION));
> + pr_debug("%s: SDHC type: 0x%08x\n",
> + mmc_hostname(host->mmc), sdhci_readl(host, MSHC2_TYPE));
> +
> + return ret;
> +
> +err_clk:
> + clk_disable_unprepare(pltfm_host->clk);
> +free_pltfm:
> + sdhci_pltfm_free(pdev);
> + return ret;
> +}
> +
> +static const struct of_device_id sdhci_sparx5_of_match[] = {
> + { .compatible = "microchip,dw-sparx5-sdhci" },
> + { }
> +};
> +MODULE_DEVICE_TABLE(of, sdhci_sparx5_of_match);
> +
> +static struct platform_driver sdhci_sparx5_driver = {
> + .driver = {
> + .name = "sdhci-sparx5",
> + .of_match_table = sdhci_sparx5_of_match,
> + .pm = &sdhci_pltfm_pmops,
> + },
> + .probe = sdhci_sparx5_probe,
> + .remove = sdhci_pltfm_unregister,
> +};
> +
> +module_platform_driver(sdhci_sparx5_driver);
> +
> +MODULE_DESCRIPTION("Sparx5 SDHCI OF driver");
> +MODULE_AUTHOR("Lars Povlsen <lars.povlsen@microchip.com>");
> +MODULE_LICENSE("GPL v2");
>