drivers/mmc/host/dw_mmc-bluefield.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (C) 2018 Mellanox Technologies.
   4  */
   5
   6 #include <linux/arm-smccc.h>
   7 #include <linux/bitfield.h>
   8 #include <linux/bitops.h>
   9 #include <linux/mmc/host.h>
  10 #include <linux/mmc/mmc.h>
  11 #include <linux/module.h>
  12 #include <linux/of.h>
  13 #include <linux/platform_device.h>
  14 #include <linux/pm_runtime.h>
  15
  16 #include "dw_mmc.h"
  17 #include "dw_mmc-pltfm.h"
  18
  19 #define UHS_REG_EXT_SAMPLE_MASK         GENMASK(22, 16)
  20 #define UHS_REG_EXT_DRIVE_MASK          GENMASK(29, 23)
  21 #define BLUEFIELD_UHS_REG_EXT_SAMPLE    2
  22 #define BLUEFIELD_UHS_REG_EXT_DRIVE     4
  23
  24 /* SMC call for RST_N */
  25 #define BLUEFIELD_SMC_SET_EMMC_RST_N    0x82000007
  26
  27 static void dw_mci_bluefield_set_ios(struct dw_mci *host, struct mmc_ios *ios)
  28 {
  29         u32 reg;
  30
  31         /* Update the Drive and Sample fields in register UHS_REG_EXT. */
  32         reg = mci_readl(host, UHS_REG_EXT);
  33         reg &= ~UHS_REG_EXT_SAMPLE_MASK;
  34         reg |= FIELD_PREP(UHS_REG_EXT_SAMPLE_MASK,
  35                           BLUEFIELD_UHS_REG_EXT_SAMPLE);
  36         reg &= ~UHS_REG_EXT_DRIVE_MASK;
  37         reg |= FIELD_PREP(UHS_REG_EXT_DRIVE_MASK, BLUEFIELD_UHS_REG_EXT_DRIVE);
  38         mci_writel(host, UHS_REG_EXT, reg);
  39 }
  40
  41 static void dw_mci_bluefield_hw_reset(struct dw_mci *host)
  42 {
  43                 struct arm_smccc_res res = { 0 };
  44
  45                 arm_smccc_smc(BLUEFIELD_SMC_SET_EMMC_RST_N, 0, 0, 0, 0, 0, 0, 0,
  46                               &res);
  47
  48                 if (res.a0)
  49                         pr_err("RST_N failed.\n");
  50 }
  51
  52 static const struct dw_mci_drv_data bluefield_drv_data = {
  53         .set_ios                = dw_mci_bluefield_set_ios,
  54         .hw_reset               = dw_mci_bluefield_hw_reset
  55 };
  56
  57 static const struct of_device_id dw_mci_bluefield_match[] = {
  58         { .compatible = "mellanox,bluefield-dw-mshc",
  59           .data = &bluefield_drv_data },
  60         {},
  61 };
  62 MODULE_DEVICE_TABLE(of, dw_mci_bluefield_match);
  63
  64 static int dw_mci_bluefield_probe(struct platform_device *pdev)
  65 {
  66         return dw_mci_pltfm_register(pdev, &bluefield_drv_data);
  67 }
  68
  69 static struct platform_driver dw_mci_bluefield_pltfm_driver = {
  70         .probe          = dw_mci_bluefield_probe,
  71         .remove         = dw_mci_pltfm_remove,
  72         .driver         = {
  73                 .name           = "dwmmc_bluefield",
  74                 .probe_type     = PROBE_PREFER_ASYNCHRONOUS,
  75                 .of_match_table = dw_mci_bluefield_match,
  76                 .pm             = &dw_mci_pltfm_pmops,
  77         },
  78 };
  79
  80 module_platform_driver(dw_mci_bluefield_pltfm_driver);
  81
  82 MODULE_DESCRIPTION("BlueField DW Multimedia Card driver");
  83 MODULE_AUTHOR("Mellanox Technologies");
  84 MODULE_LICENSE("GPL v2");