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

Lars Povlsen
2020-07-24T11:32:31Z

Ulf Hansson writes:

> On Wed, 22 Jul 2020 at 13:54, Lars Povlsen <lars.povlsen@microchip.com> wrote:
>>
>>
>> Adrian Hunter writes:
>>
>> > On 18/06/20 5:13 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>
>> >
>> > Acked-by: Adrian Hunter <adrian.hunter@intel.com>
>> >
>>
>> Adrian,
>>
>> Thanks for the ack. I was expecting to see this in linux-next, anything
>> holding it back?
>>
>> pinctrl and hwmon drivers have been merged.
>>
>> Thanks,
>
> Hi Lars,
>
> Looks like you got some feedback on the DT patch (patch1/3) from Rob.
> I didn't find that you have addressed them and therefore I am holding
> back on the $subject patch as well.
>

Uffe, thank you for responding.

The automated checker complains about the inclusion of a header file
(#include <dt-bindings/clock/microchip,sparx5.h>) in the example. The
header file itself is part of the "parent" patch series sent to arm-soc,
but is needed to make the example complete.

I e-mailed Rob about how to handle this, but never got a reply.

Can you suggest how to deal with this? I have checked the schema with
dt_binding_check manually - with the header file in place.

I can of course remove the include and associated properties, but that
will make the example incomplete and irrelevant.

---Lars

> Please fix the DT patch and re-submit a new version of the series.
>
> Kind regards
> Uffe
>
>
>>
>> ---Lars
>>
>> >> ---
>> >> 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");
>> >>
>>
>> --
>> Lars Povlsen,
>> Microchip

--
Lars Povlsen,
Microchip