1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * drivers/mmc/host/sdhci-of-sparx5.c
4 *
5 * MCHP Sparx5 SoC Secure Digital Host Controller Interface.
6 *
7 * Copyright (c) 2019 Microchip Inc.
8 *
9 * Author: Lars Povlsen <lars.povlsen@microchip.com>
10 */
11
12 #include <linux/sizes.h>
13 #include <linux/delay.h>
14 #include <linux/module.h>
15 #include <linux/regmap.h>
16 #include <linux/of_device.h>
17 #include <linux/mfd/syscon.h>
18 #include <linux/dma-mapping.h>
19
20 #include "sdhci-pltfm.h"
21
22 #define CPU_REGS_GENERAL_CTRL (0x22 * 4)
23 #define MSHC_DLY_CC_MASK GENMASK(16, 13)
24 #define MSHC_DLY_CC_SHIFT 13
25 #define MSHC_DLY_CC_MAX 15
26
27 #define CPU_REGS_PROC_CTRL (0x2C * 4)
28 #define ACP_CACHE_FORCE_ENA BIT(4)
29 #define ACP_AWCACHE BIT(3)
30 #define ACP_ARCACHE BIT(2)
31 #define ACP_CACHE_MASK (ACP_CACHE_FORCE_ENA|ACP_AWCACHE|ACP_ARCACHE)
32
33 #define MSHC2_VERSION 0x500 /* Off 0x140, reg 0x0 */
34 #define MSHC2_TYPE 0x504 /* Off 0x140, reg 0x1 */
35 #define MSHC2_EMMC_CTRL 0x52c /* Off 0x140, reg 0xB */
36 #define MSHC2_EMMC_CTRL_EMMC_RST_N BIT(2)
37 #define MSHC2_EMMC_CTRL_IS_EMMC BIT(0)
38
39 struct sdhci_sparx5_data {
40 struct sdhci_host *host;
41 struct regmap *cpu_ctrl;
42 int delay_clock;
43 };
44
45 #define BOUNDARY_OK(addr, len) \
46 ((addr | (SZ_128M - 1)) == ((addr + len - 1) | (SZ_128M - 1)))
47
48 /*
49 * If DMA addr spans 128MB boundary, we split the DMA transfer into two
50 * so that each DMA transfer doesn't exceed the boundary.
51 */
sdhci_sparx5_adma_write_desc(struct sdhci_host * host,void ** desc,dma_addr_t addr,int len,unsigned int cmd)52 static void sdhci_sparx5_adma_write_desc(struct sdhci_host *host, void **desc,
53 dma_addr_t addr, int len,
54 unsigned int cmd)
55 {
56 int tmplen, offset;
57
58 if (likely(!len || BOUNDARY_OK(addr, len))) {
59 sdhci_adma_write_desc(host, desc, addr, len, cmd);
60 return;
61 }
62
63 pr_debug("%s: write_desc: splitting dma len %d, offset %pad\n",
64 mmc_hostname(host->mmc), len, &addr);
65
66 offset = addr & (SZ_128M - 1);
67 tmplen = SZ_128M - offset;
68 sdhci_adma_write_desc(host, desc, addr, tmplen, cmd);
69
70 addr += tmplen;
71 len -= tmplen;
72 sdhci_adma_write_desc(host, desc, addr, len, cmd);
73 }
74
sparx5_set_cacheable(struct sdhci_host * host,u32 value)75 static void sparx5_set_cacheable(struct sdhci_host *host, u32 value)
76 {
77 struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
78 struct sdhci_sparx5_data *sdhci_sparx5 = sdhci_pltfm_priv(pltfm_host);
79
80 pr_debug("%s: Set Cacheable = 0x%x\n", mmc_hostname(host->mmc), value);
81
82 /* Update ACP caching attributes in HW */
83 regmap_update_bits(sdhci_sparx5->cpu_ctrl,
84 CPU_REGS_PROC_CTRL, ACP_CACHE_MASK, value);
85 }
86
sparx5_set_delay(struct sdhci_host * host,u8 value)87 static void sparx5_set_delay(struct sdhci_host *host, u8 value)
88 {
89 struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
90 struct sdhci_sparx5_data *sdhci_sparx5 = sdhci_pltfm_priv(pltfm_host);
91
92 pr_debug("%s: Set DLY_CC = %u\n", mmc_hostname(host->mmc), value);
93
94 /* Update DLY_CC in HW */
95 regmap_update_bits(sdhci_sparx5->cpu_ctrl,
96 CPU_REGS_GENERAL_CTRL,
97 MSHC_DLY_CC_MASK,
98 (value << MSHC_DLY_CC_SHIFT));
99 }
100
sdhci_sparx5_set_emmc(struct sdhci_host * host)101 static void sdhci_sparx5_set_emmc(struct sdhci_host *host)
102 {
103 if (!mmc_card_is_removable(host->mmc)) {
104 u8 value;
105
106 value = sdhci_readb(host, MSHC2_EMMC_CTRL);
107 if (!(value & MSHC2_EMMC_CTRL_IS_EMMC)) {
108 value |= MSHC2_EMMC_CTRL_IS_EMMC;
109 pr_debug("%s: Set EMMC_CTRL: 0x%08x\n",
110 mmc_hostname(host->mmc), value);
111 sdhci_writeb(host, value, MSHC2_EMMC_CTRL);
112 }
113 }
114 }
115
sdhci_sparx5_reset_emmc(struct sdhci_host * host)116 static void sdhci_sparx5_reset_emmc(struct sdhci_host *host)
117 {
118 u8 value;
119
120 pr_debug("%s: Toggle EMMC_CTRL.EMMC_RST_N\n", mmc_hostname(host->mmc));
121 value = sdhci_readb(host, MSHC2_EMMC_CTRL) &
122 ~MSHC2_EMMC_CTRL_EMMC_RST_N;
123 sdhci_writeb(host, value, MSHC2_EMMC_CTRL);
124 /* For eMMC, minimum is 1us but give it 10us for good measure */
125 usleep_range(10, 20);
126 sdhci_writeb(host, value | MSHC2_EMMC_CTRL_EMMC_RST_N,
127 MSHC2_EMMC_CTRL);
128 /* For eMMC, minimum is 200us but give it 300us for good measure */
129 usleep_range(300, 400);
130 }
131
sdhci_sparx5_reset(struct sdhci_host * host,u8 mask)132 static void sdhci_sparx5_reset(struct sdhci_host *host, u8 mask)
133 {
134 pr_debug("%s: *** RESET: mask %d\n", mmc_hostname(host->mmc), mask);
135
136 sdhci_reset(host, mask);
137
138 /* Be sure CARD_IS_EMMC stays set */
139 sdhci_sparx5_set_emmc(host);
140 }
141
142 static const struct sdhci_ops sdhci_sparx5_ops = {
143 .set_clock = sdhci_set_clock,
144 .set_bus_width = sdhci_set_bus_width,
145 .set_uhs_signaling = sdhci_set_uhs_signaling,
146 .get_max_clock = sdhci_pltfm_clk_get_max_clock,
147 .reset = sdhci_sparx5_reset,
148 .adma_write_desc = sdhci_sparx5_adma_write_desc,
149 };
150
151 static const struct sdhci_pltfm_data sdhci_sparx5_pdata = {
152 .quirks = 0,
153 .quirks2 = SDHCI_QUIRK2_HOST_NO_CMD23 | /* Controller issue */
154 SDHCI_QUIRK2_NO_1_8_V, /* No sdr104, ddr50, etc */
155 .ops = &sdhci_sparx5_ops,
156 };
157
sdhci_sparx5_probe(struct platform_device * pdev)158 static int sdhci_sparx5_probe(struct platform_device *pdev)
159 {
160 int ret;
161 const char *syscon = "microchip,sparx5-cpu-syscon";
162 struct sdhci_host *host;
163 struct sdhci_pltfm_host *pltfm_host;
164 struct sdhci_sparx5_data *sdhci_sparx5;
165 struct device_node *np = pdev->dev.of_node;
166 u32 value;
167 u32 extra;
168
169 host = sdhci_pltfm_init(pdev, &sdhci_sparx5_pdata,
170 sizeof(*sdhci_sparx5));
171
172 if (IS_ERR(host))
173 return PTR_ERR(host);
174
175 /*
176 * extra adma table cnt for cross 128M boundary handling.
177 */
178 extra = DIV_ROUND_UP_ULL(dma_get_required_mask(&pdev->dev), SZ_128M);
179 if (extra > SDHCI_MAX_SEGS)
180 extra = SDHCI_MAX_SEGS;
181 host->adma_table_cnt += extra;
182
183 pltfm_host = sdhci_priv(host);
184 sdhci_sparx5 = sdhci_pltfm_priv(pltfm_host);
185 sdhci_sparx5->host = host;
186
187 pltfm_host->clk = devm_clk_get(&pdev->dev, "core");
188 if (IS_ERR(pltfm_host->clk)) {
189 ret = PTR_ERR(pltfm_host->clk);
190 dev_err(&pdev->dev, "failed to get core clk: %d\n", ret);
191 goto free_pltfm;
192 }
193 ret = clk_prepare_enable(pltfm_host->clk);
194 if (ret)
195 goto free_pltfm;
196
197 if (!of_property_read_u32(np, "microchip,clock-delay", &value) &&
198 (value > 0 && value <= MSHC_DLY_CC_MAX))
199 sdhci_sparx5->delay_clock = value;
200
201 sdhci_get_of_property(pdev);
202
203 ret = mmc_of_parse(host->mmc);
204 if (ret)
205 goto err_clk;
206
207 sdhci_sparx5->cpu_ctrl = syscon_regmap_lookup_by_compatible(syscon);
208 if (IS_ERR(sdhci_sparx5->cpu_ctrl)) {
209 dev_err(&pdev->dev, "No CPU syscon regmap !\n");
210 ret = PTR_ERR(sdhci_sparx5->cpu_ctrl);
211 goto err_clk;
212 }
213
214 if (sdhci_sparx5->delay_clock >= 0)
215 sparx5_set_delay(host, sdhci_sparx5->delay_clock);
216
217 if (!mmc_card_is_removable(host->mmc)) {
218 /* Do a HW reset of eMMC card */
219 sdhci_sparx5_reset_emmc(host);
220 /* Update EMMC_CTRL */
221 sdhci_sparx5_set_emmc(host);
222 /* If eMMC, disable SD and SDIO */
223 host->mmc->caps2 |= (MMC_CAP2_NO_SDIO|MMC_CAP2_NO_SD);
224 }
225
226 ret = sdhci_add_host(host);
227 if (ret)
228 goto err_clk;
229
230 /* Set AXI bus master to use un-cached access (for DMA) */
231 if (host->flags & (SDHCI_USE_SDMA | SDHCI_USE_ADMA) &&
232 IS_ENABLED(CONFIG_DMA_DECLARE_COHERENT))
233 sparx5_set_cacheable(host, ACP_CACHE_FORCE_ENA);
234
235 pr_debug("%s: SDHC version: 0x%08x\n",
236 mmc_hostname(host->mmc), sdhci_readl(host, MSHC2_VERSION));
237 pr_debug("%s: SDHC type: 0x%08x\n",
238 mmc_hostname(host->mmc), sdhci_readl(host, MSHC2_TYPE));
239
240 return ret;
241
242 err_clk:
243 clk_disable_unprepare(pltfm_host->clk);
244 free_pltfm:
245 sdhci_pltfm_free(pdev);
246 return ret;
247 }
248
249 static const struct of_device_id sdhci_sparx5_of_match[] = {
250 { .compatible = "microchip,dw-sparx5-sdhci" },
251 { }
252 };
253 MODULE_DEVICE_TABLE(of, sdhci_sparx5_of_match);
254
255 static struct platform_driver sdhci_sparx5_driver = {
256 .driver = {
257 .name = "sdhci-sparx5",
258 .probe_type = PROBE_PREFER_ASYNCHRONOUS,
259 .of_match_table = sdhci_sparx5_of_match,
260 .pm = &sdhci_pltfm_pmops,
261 },
262 .probe = sdhci_sparx5_probe,
263 .remove = sdhci_pltfm_unregister,
264 };
265
266 module_platform_driver(sdhci_sparx5_driver);
267
268 MODULE_DESCRIPTION("Sparx5 SDHCI OF driver");
269 MODULE_AUTHOR("Lars Povlsen <lars.povlsen@microchip.com>");
270 MODULE_LICENSE("GPL v2");
271