1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * SDHCI driver for Synopsys DWC_MSHC controller
4  *
5  * Copyright (C) 2018 Synopsys, Inc. (www.synopsys.com)
6  *
7  * Authors:
8  *	Prabu Thangamuthu <prabu.t@synopsys.com>
9  *	Manjunath M B <manjumb@synopsys.com>
10  */
11 
12 #include "sdhci.h"
13 #include "sdhci-pci.h"
14 
15 #define SDHCI_VENDOR_PTR_R	0xE8
16 
17 /* Synopsys vendor specific registers */
18 #define SDHC_GPIO_OUT		0x34
19 #define SDHC_AT_CTRL_R		0x40
20 #define SDHC_SW_TUNE_EN		0x00000010
21 
22 /* MMCM DRP */
23 #define SDHC_MMCM_DIV_REG	0x1020
24 #define DIV_REG_100_MHZ		0x1145
25 #define DIV_REG_200_MHZ		0x1083
26 #define SDHC_MMCM_CLKFBOUT	0x1024
27 #define CLKFBOUT_100_MHZ	0x0000
28 #define CLKFBOUT_200_MHZ	0x0080
29 #define SDHC_CCLK_MMCM_RST	0x00000001
30 
31 static void sdhci_snps_set_clock(struct sdhci_host *host, unsigned int clock)
32 {
33 	u16 clk;
34 	u32 reg, vendor_ptr;
35 
36 	vendor_ptr = sdhci_readw(host, SDHCI_VENDOR_PTR_R);
37 
38 	/* Disable software managed rx tuning */
39 	reg = sdhci_readl(host, (SDHC_AT_CTRL_R + vendor_ptr));
40 	reg &= ~SDHC_SW_TUNE_EN;
41 	sdhci_writel(host, reg, (SDHC_AT_CTRL_R + vendor_ptr));
42 
43 	if (clock <= 52000000) {
44 		sdhci_set_clock(host, clock);
45 	} else {
46 		/* Assert reset to MMCM */
47 		reg = sdhci_readl(host, (SDHC_GPIO_OUT + vendor_ptr));
48 		reg |= SDHC_CCLK_MMCM_RST;
49 		sdhci_writel(host, reg, (SDHC_GPIO_OUT + vendor_ptr));
50 
51 		/* Configure MMCM */
52 		if (clock == 100000000) {
53 			sdhci_writel(host, DIV_REG_100_MHZ, SDHC_MMCM_DIV_REG);
54 			sdhci_writel(host, CLKFBOUT_100_MHZ,
55 					SDHC_MMCM_CLKFBOUT);
56 		} else {
57 			sdhci_writel(host, DIV_REG_200_MHZ, SDHC_MMCM_DIV_REG);
58 			sdhci_writel(host, CLKFBOUT_200_MHZ,
59 					SDHC_MMCM_CLKFBOUT);
60 		}
61 
62 		/* De-assert reset to MMCM */
63 		reg = sdhci_readl(host, (SDHC_GPIO_OUT + vendor_ptr));
64 		reg &= ~SDHC_CCLK_MMCM_RST;
65 		sdhci_writel(host, reg, (SDHC_GPIO_OUT + vendor_ptr));
66 
67 		/* Enable clock */
68 		clk = SDHCI_PROG_CLOCK_MODE | SDHCI_CLOCK_INT_EN |
69 			SDHCI_CLOCK_CARD_EN;
70 		sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
71 	}
72 }
73 
74 static const struct sdhci_ops sdhci_snps_ops = {
75 	.set_clock	= sdhci_snps_set_clock,
76 	.enable_dma	= sdhci_pci_enable_dma,
77 	.set_bus_width	= sdhci_set_bus_width,
78 	.reset		= sdhci_reset,
79 	.set_uhs_signaling = sdhci_set_uhs_signaling,
80 };
81 
82 const struct sdhci_pci_fixes sdhci_snps = {
83 	.ops		= &sdhci_snps_ops,
84 };
85