xref: /linux/drivers/mmc/host/dw_mmc-bluefield.c (revision a1ff5a7d78a036d6c2178ee5acd6ba4946243800)
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 
dw_mci_bluefield_set_ios(struct dw_mci * host,struct mmc_ios * ios)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 
dw_mci_bluefield_hw_reset(struct dw_mci * host)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 
dw_mci_bluefield_probe(struct platform_device * pdev)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_new	= 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");
85