xref: /openbmc/linux/drivers/mmc/host/mmci_qcom_dml.c (revision 293d5b43)
1 /*
2  *
3  * Copyright (c) 2011, The Linux Foundation. All rights reserved.
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License version 2 and
7  * only version 2 as published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  */
15 #include <linux/of.h>
16 #include <linux/of_dma.h>
17 #include <linux/bitops.h>
18 #include <linux/mmc/host.h>
19 #include <linux/mmc/card.h>
20 #include "mmci.h"
21 
22 /* Registers */
23 #define DML_CONFIG			0x00
24 #define PRODUCER_CRCI_MSK		GENMASK(1, 0)
25 #define PRODUCER_CRCI_DISABLE		0
26 #define PRODUCER_CRCI_X_SEL		BIT(0)
27 #define PRODUCER_CRCI_Y_SEL		BIT(1)
28 #define CONSUMER_CRCI_MSK		GENMASK(3, 2)
29 #define CONSUMER_CRCI_DISABLE		0
30 #define CONSUMER_CRCI_X_SEL		BIT(2)
31 #define CONSUMER_CRCI_Y_SEL		BIT(3)
32 #define PRODUCER_TRANS_END_EN		BIT(4)
33 #define BYPASS				BIT(16)
34 #define DIRECT_MODE			BIT(17)
35 #define INFINITE_CONS_TRANS		BIT(18)
36 
37 #define DML_SW_RESET			0x08
38 #define DML_PRODUCER_START		0x0c
39 #define DML_CONSUMER_START		0x10
40 #define DML_PRODUCER_PIPE_LOGICAL_SIZE	0x14
41 #define DML_CONSUMER_PIPE_LOGICAL_SIZE	0x18
42 #define DML_PIPE_ID			0x1c
43 #define PRODUCER_PIPE_ID_SHFT		0
44 #define PRODUCER_PIPE_ID_MSK		GENMASK(4, 0)
45 #define CONSUMER_PIPE_ID_SHFT		16
46 #define CONSUMER_PIPE_ID_MSK		GENMASK(20, 16)
47 
48 #define DML_PRODUCER_BAM_BLOCK_SIZE	0x24
49 #define DML_PRODUCER_BAM_TRANS_SIZE	0x28
50 
51 /* other definitions */
52 #define PRODUCER_PIPE_LOGICAL_SIZE	4096
53 #define CONSUMER_PIPE_LOGICAL_SIZE	4096
54 
55 #define DML_OFFSET			0x800
56 
57 void dml_start_xfer(struct mmci_host *host, struct mmc_data *data)
58 {
59 	u32 config;
60 	void __iomem *base = host->base + DML_OFFSET;
61 
62 	if (data->flags & MMC_DATA_READ) {
63 		/* Read operation: configure DML for producer operation */
64 		/* Set producer CRCI-x and disable consumer CRCI */
65 		config = readl_relaxed(base + DML_CONFIG);
66 		config = (config & ~PRODUCER_CRCI_MSK) | PRODUCER_CRCI_X_SEL;
67 		config = (config & ~CONSUMER_CRCI_MSK) | CONSUMER_CRCI_DISABLE;
68 		writel_relaxed(config, base + DML_CONFIG);
69 
70 		/* Set the Producer BAM block size */
71 		writel_relaxed(data->blksz, base + DML_PRODUCER_BAM_BLOCK_SIZE);
72 
73 		/* Set Producer BAM Transaction size */
74 		writel_relaxed(data->blocks * data->blksz,
75 			       base + DML_PRODUCER_BAM_TRANS_SIZE);
76 		/* Set Producer Transaction End bit */
77 		config = readl_relaxed(base + DML_CONFIG);
78 		config |= PRODUCER_TRANS_END_EN;
79 		writel_relaxed(config, base + DML_CONFIG);
80 		/* Trigger producer */
81 		writel_relaxed(1, base + DML_PRODUCER_START);
82 	} else {
83 		/* Write operation: configure DML for consumer operation */
84 		/* Set consumer CRCI-x and disable producer CRCI*/
85 		config = readl_relaxed(base + DML_CONFIG);
86 		config = (config & ~CONSUMER_CRCI_MSK) | CONSUMER_CRCI_X_SEL;
87 		config = (config & ~PRODUCER_CRCI_MSK) | PRODUCER_CRCI_DISABLE;
88 		writel_relaxed(config, base + DML_CONFIG);
89 		/* Clear Producer Transaction End bit */
90 		config = readl_relaxed(base + DML_CONFIG);
91 		config &= ~PRODUCER_TRANS_END_EN;
92 		writel_relaxed(config, base + DML_CONFIG);
93 		/* Trigger consumer */
94 		writel_relaxed(1, base + DML_CONSUMER_START);
95 	}
96 
97 	/* make sure the dml is configured before dma is triggered */
98 	wmb();
99 }
100 
101 static int of_get_dml_pipe_index(struct device_node *np, const char *name)
102 {
103 	int index;
104 	struct of_phandle_args	dma_spec;
105 
106 	index = of_property_match_string(np, "dma-names", name);
107 
108 	if (index < 0)
109 		return -ENODEV;
110 
111 	if (of_parse_phandle_with_args(np, "dmas", "#dma-cells", index,
112 				       &dma_spec))
113 		return -ENODEV;
114 
115 	if (dma_spec.args_count)
116 		return dma_spec.args[0];
117 
118 	return -ENODEV;
119 }
120 
121 /* Initialize the dml hardware connected to SD Card controller */
122 int dml_hw_init(struct mmci_host *host, struct device_node *np)
123 {
124 	u32 config;
125 	void __iomem *base;
126 	int consumer_id, producer_id;
127 
128 	consumer_id = of_get_dml_pipe_index(np, "tx");
129 	producer_id = of_get_dml_pipe_index(np, "rx");
130 
131 	if (producer_id < 0 || consumer_id < 0)
132 		return -ENODEV;
133 
134 	base = host->base + DML_OFFSET;
135 
136 	/* Reset the DML block */
137 	writel_relaxed(1, base + DML_SW_RESET);
138 
139 	/* Disable the producer and consumer CRCI */
140 	config = (PRODUCER_CRCI_DISABLE | CONSUMER_CRCI_DISABLE);
141 	/*
142 	 * Disable the bypass mode. Bypass mode will only be used
143 	 * if data transfer is to happen in PIO mode and don't
144 	 * want the BAM interface to connect with SDCC-DML.
145 	 */
146 	config &= ~BYPASS;
147 	/*
148 	 * Disable direct mode as we don't DML to MASTER the AHB bus.
149 	 * BAM connected with DML should MASTER the AHB bus.
150 	 */
151 	config &= ~DIRECT_MODE;
152 	/*
153 	 * Disable infinite mode transfer as we won't be doing any
154 	 * infinite size data transfers. All data transfer will be
155 	 * of finite data size.
156 	 */
157 	config &= ~INFINITE_CONS_TRANS;
158 	writel_relaxed(config, base + DML_CONFIG);
159 
160 	/*
161 	 * Initialize the logical BAM pipe size for producer
162 	 * and consumer.
163 	 */
164 	writel_relaxed(PRODUCER_PIPE_LOGICAL_SIZE,
165 		       base + DML_PRODUCER_PIPE_LOGICAL_SIZE);
166 	writel_relaxed(CONSUMER_PIPE_LOGICAL_SIZE,
167 		       base + DML_CONSUMER_PIPE_LOGICAL_SIZE);
168 
169 	/* Initialize Producer/consumer pipe id */
170 	writel_relaxed(producer_id | (consumer_id << CONSUMER_PIPE_ID_SHFT),
171 		       base + DML_PIPE_ID);
172 
173 	/* Make sure dml intialization is finished */
174 	mb();
175 
176 	return 0;
177 }
178