2 * Copyright (C) 2013 Broadcom Corporation
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License as
6 * published by the Free Software Foundation version 2.
8 * This program is distributed "as is" WITHOUT ANY WARRANTY of any
9 * kind, whether express or implied; without even the implied warranty
10 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 * GNU General Public License for more details.
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/delay.h>
17 #include <linux/highmem.h>
18 #include <linux/platform_device.h>
19 #include <linux/mmc/host.h>
21 #include <linux/gpio.h>
22 #include <linux/clk.h>
23 #include <linux/regulator/consumer.h>
25 #include <linux/of_device.h>
26 #include <linux/of_gpio.h>
27 #include <linux/mmc/slot-gpio.h>
29 #include "sdhci-pltfm.h"
32 #define SDHCI_SOFT_RESET 0x01000000
33 #define KONA_SDHOST_CORECTRL 0x8000
34 #define KONA_SDHOST_CD_PINCTRL 0x00000008
35 #define KONA_SDHOST_STOP_HCLK 0x00000004
36 #define KONA_SDHOST_RESET 0x00000002
37 #define KONA_SDHOST_EN 0x00000001
39 #define KONA_SDHOST_CORESTAT 0x8004
40 #define KONA_SDHOST_WP 0x00000002
41 #define KONA_SDHOST_CD_SW 0x00000001
43 #define KONA_SDHOST_COREIMR 0x8008
44 #define KONA_SDHOST_IP 0x00000001
46 #define KONA_SDHOST_COREISR 0x800C
47 #define KONA_SDHOST_COREIMSR 0x8010
48 #define KONA_SDHOST_COREDBG1 0x8014
49 #define KONA_SDHOST_COREGPO_MASK 0x8018
51 #define SD_DETECT_GPIO_DEBOUNCE_128MS 128
53 #define KONA_MMC_AUTOSUSPEND_DELAY (50)
55 struct sdhci_bcm_kona_dev
{
56 struct mutex write_lock
; /* protect back to back writes */
60 static int sdhci_bcm_kona_sd_reset(struct sdhci_host
*host
)
63 unsigned long timeout
;
65 /* This timeout should be sufficent for core to reset */
66 timeout
= jiffies
+ msecs_to_jiffies(100);
68 /* reset the host using the top level reset */
69 val
= sdhci_readl(host
, KONA_SDHOST_CORECTRL
);
70 val
|= KONA_SDHOST_RESET
;
71 sdhci_writel(host
, val
, KONA_SDHOST_CORECTRL
);
73 while (!(sdhci_readl(host
, KONA_SDHOST_CORECTRL
) & KONA_SDHOST_RESET
)) {
74 if (time_is_before_jiffies(timeout
)) {
75 pr_err("Error: sd host is stuck in reset!!!\n");
80 /* bring the host out of reset */
81 val
= sdhci_readl(host
, KONA_SDHOST_CORECTRL
);
82 val
&= ~KONA_SDHOST_RESET
;
85 * Back-to-Back register write needs a delay of 1ms at bootup (min 10uS)
86 * Back-to-Back writes to same register needs delay when SD bus clock
87 * is very low w.r.t AHB clock, mainly during boot-time and during card
90 usleep_range(1000, 5000);
91 sdhci_writel(host
, val
, KONA_SDHOST_CORECTRL
);
96 static void sdhci_bcm_kona_sd_init(struct sdhci_host
*host
)
100 /* enable the interrupt from the IP core */
101 val
= sdhci_readl(host
, KONA_SDHOST_COREIMR
);
102 val
|= KONA_SDHOST_IP
;
103 sdhci_writel(host
, val
, KONA_SDHOST_COREIMR
);
105 /* Enable the AHB clock gating module to the host */
106 val
= sdhci_readl(host
, KONA_SDHOST_CORECTRL
);
107 val
|= KONA_SDHOST_EN
;
110 * Back-to-Back register write needs a delay of 1ms at bootup (min 10uS)
111 * Back-to-Back writes to same register needs delay when SD bus clock
112 * is very low w.r.t AHB clock, mainly during boot-time and during card
115 usleep_range(1000, 5000);
116 sdhci_writel(host
, val
, KONA_SDHOST_CORECTRL
);
120 * Software emulation of the SD card insertion/removal. Set insert=1 for insert
121 * and insert=0 for removal. The card detection is done by GPIO. For Broadcom
122 * IP to function properly the bit 0 of CORESTAT register needs to be set/reset
123 * to generate the CD IRQ handled in sdhci.c which schedules card_tasklet.
125 static int sdhci_bcm_kona_sd_card_emulate(struct sdhci_host
*host
, int insert
)
127 struct sdhci_pltfm_host
*pltfm_priv
= sdhci_priv(host
);
128 struct sdhci_bcm_kona_dev
*kona_dev
= sdhci_pltfm_priv(pltfm_priv
);
132 * Back-to-Back register write needs a delay of min 10uS.
133 * Back-to-Back writes to same register needs delay when SD bus clock
134 * is very low w.r.t AHB clock, mainly during boot-time and during card
138 mutex_lock(&kona_dev
->write_lock
);
140 val
= sdhci_readl(host
, KONA_SDHOST_CORESTAT
);
145 ret
= mmc_gpio_get_ro(host
->mmc
);
147 val
= (val
& ~KONA_SDHOST_WP
) |
148 ((ret
) ? KONA_SDHOST_WP
: 0);
150 val
|= KONA_SDHOST_CD_SW
;
151 sdhci_writel(host
, val
, KONA_SDHOST_CORESTAT
);
153 val
&= ~KONA_SDHOST_CD_SW
;
154 sdhci_writel(host
, val
, KONA_SDHOST_CORESTAT
);
156 mutex_unlock(&kona_dev
->write_lock
);
162 * SD card interrupt event callback
164 static void sdhci_bcm_kona_card_event(struct sdhci_host
*host
)
166 if (mmc_gpio_get_cd(host
->mmc
) > 0) {
167 dev_dbg(mmc_dev(host
->mmc
),
169 sdhci_bcm_kona_sd_card_emulate(host
, 1);
171 dev_dbg(mmc_dev(host
->mmc
),
173 sdhci_bcm_kona_sd_card_emulate(host
, 0);
177 static void sdhci_bcm_kona_init_74_clocks(struct sdhci_host
*host
,
181 * JEDEC and SD spec specify supplying 74 continuous clocks to
182 * device after power up. With minimum bus (100KHz) that
183 * that translates to 740us
185 if (power_mode
!= MMC_POWER_OFF
)
189 static struct sdhci_ops sdhci_bcm_kona_ops
= {
190 .set_clock
= sdhci_set_clock
,
191 .get_max_clock
= sdhci_pltfm_clk_get_max_clock
,
192 .get_timeout_clock
= sdhci_pltfm_clk_get_max_clock
,
193 .platform_send_init_74_clocks
= sdhci_bcm_kona_init_74_clocks
,
194 .set_bus_width
= sdhci_set_bus_width
,
195 .reset
= sdhci_reset
,
196 .set_uhs_signaling
= sdhci_set_uhs_signaling
,
197 .card_event
= sdhci_bcm_kona_card_event
,
200 static struct sdhci_pltfm_data sdhci_pltfm_data_kona
= {
201 .ops
= &sdhci_bcm_kona_ops
,
202 .quirks
= SDHCI_QUIRK_NO_CARD_NO_RESET
|
203 SDHCI_QUIRK_BROKEN_TIMEOUT_VAL
| SDHCI_QUIRK_32BIT_DMA_ADDR
|
204 SDHCI_QUIRK_32BIT_DMA_SIZE
| SDHCI_QUIRK_32BIT_ADMA_SIZE
|
205 SDHCI_QUIRK_FORCE_BLK_SZ_2048
|
206 SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN
,
209 static const struct of_device_id sdhci_bcm_kona_of_match
[] = {
210 { .compatible
= "brcm,kona-sdhci"},
211 { .compatible
= "bcm,kona-sdhci"}, /* deprecated name */
214 MODULE_DEVICE_TABLE(of
, sdhci_bcm_kona_of_match
);
216 static int sdhci_bcm_kona_probe(struct platform_device
*pdev
)
218 struct sdhci_bcm_kona_dev
*kona_dev
= NULL
;
219 struct sdhci_pltfm_host
*pltfm_priv
;
220 struct device
*dev
= &pdev
->dev
;
221 struct sdhci_host
*host
;
226 host
= sdhci_pltfm_init(pdev
, &sdhci_pltfm_data_kona
,
229 return PTR_ERR(host
);
231 dev_dbg(dev
, "%s: inited. IOADDR=%p\n", __func__
, host
->ioaddr
);
233 pltfm_priv
= sdhci_priv(host
);
235 kona_dev
= sdhci_pltfm_priv(pltfm_priv
);
236 mutex_init(&kona_dev
->write_lock
);
238 ret
= mmc_of_parse(host
->mmc
);
242 if (!host
->mmc
->f_max
) {
243 dev_err(&pdev
->dev
, "Missing max-freq for SDHCI cfg\n");
248 /* Get and enable the core clock */
249 pltfm_priv
->clk
= devm_clk_get(dev
, NULL
);
250 if (IS_ERR(pltfm_priv
->clk
)) {
251 dev_err(dev
, "Failed to get core clock\n");
252 ret
= PTR_ERR(pltfm_priv
->clk
);
256 ret
= clk_set_rate(pltfm_priv
->clk
, host
->mmc
->f_max
);
258 dev_err(dev
, "Failed to set rate core clock\n");
262 ret
= clk_prepare_enable(pltfm_priv
->clk
);
264 dev_err(dev
, "Failed to enable core clock\n");
268 dev_dbg(dev
, "non-removable=%c\n",
269 mmc_card_is_removable(host
->mmc
) ? 'N' : 'Y');
270 dev_dbg(dev
, "cd_gpio %c, wp_gpio %c\n",
271 (mmc_gpio_get_cd(host
->mmc
) != -ENOSYS
) ? 'Y' : 'N',
272 (mmc_gpio_get_ro(host
->mmc
) != -ENOSYS
) ? 'Y' : 'N');
274 if (!mmc_card_is_removable(host
->mmc
))
275 host
->quirks
|= SDHCI_QUIRK_BROKEN_CARD_DETECTION
;
277 dev_dbg(dev
, "is_8bit=%c\n",
278 (host
->mmc
->caps
& MMC_CAP_8_BIT_DATA
) ? 'Y' : 'N');
280 ret
= sdhci_bcm_kona_sd_reset(host
);
282 goto err_clk_disable
;
284 sdhci_bcm_kona_sd_init(host
);
286 ret
= sdhci_add_host(host
);
288 dev_err(dev
, "Failed sdhci_add_host\n");
292 /* if device is eMMC, emulate card insert right here */
293 if (!mmc_card_is_removable(host
->mmc
)) {
294 ret
= sdhci_bcm_kona_sd_card_emulate(host
, 1);
297 "unable to emulate card insertion\n");
298 goto err_remove_host
;
302 * Since the card detection GPIO interrupt is configured to be
303 * edge sensitive, check the initial GPIO value here, emulate
304 * only if the card is present
306 if (mmc_gpio_get_cd(host
->mmc
) > 0)
307 sdhci_bcm_kona_sd_card_emulate(host
, 1);
309 dev_dbg(dev
, "initialized properly\n");
313 sdhci_remove_host(host
, 0);
316 sdhci_bcm_kona_sd_reset(host
);
319 clk_disable_unprepare(pltfm_priv
->clk
);
322 sdhci_pltfm_free(pdev
);
324 dev_err(dev
, "Probing of sdhci-pltfm failed: %d\n", ret
);
328 static struct platform_driver sdhci_bcm_kona_driver
= {
330 .name
= "sdhci-kona",
331 .pm
= &sdhci_pltfm_pmops
,
332 .of_match_table
= sdhci_bcm_kona_of_match
,
334 .probe
= sdhci_bcm_kona_probe
,
335 .remove
= sdhci_pltfm_unregister
,
337 module_platform_driver(sdhci_bcm_kona_driver
);
339 MODULE_DESCRIPTION("SDHCI driver for Broadcom Kona platform");
340 MODULE_AUTHOR("Broadcom");
341 MODULE_LICENSE("GPL v2");