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17c50b70
JE
1/*
2 * Memory controller driver for ARM PrimeCell PL172
3 * PrimeCell MultiPort Memory Controller (PL172)
4 *
5 * Copyright (C) 2015 Joachim Eastwood <manabian@gmail.com>
6 *
7 * Based on:
8 * TI AEMIF driver, Copyright (C) 2010 - 2013 Texas Instruments Inc.
9 *
10 * This file is licensed under the terms of the GNU General Public
11 * License version 2. This program is licensed "as is" without any
12 * warranty of any kind, whether express or implied.
13 */
14
15#include <linux/amba/bus.h>
16#include <linux/clk.h>
17#include <linux/device.h>
18#include <linux/err.h>
19#include <linux/init.h>
20#include <linux/io.h>
21#include <linux/kernel.h>
22#include <linux/module.h>
23#include <linux/of.h>
24#include <linux/of_platform.h>
25#include <linux/time.h>
26
27#define MPMC_STATIC_CFG(n) (0x200 + 0x20 * n)
28#define MPMC_STATIC_CFG_MW_8BIT 0x0
29#define MPMC_STATIC_CFG_MW_16BIT 0x1
30#define MPMC_STATIC_CFG_MW_32BIT 0x2
31#define MPMC_STATIC_CFG_PM BIT(3)
32#define MPMC_STATIC_CFG_PC BIT(6)
33#define MPMC_STATIC_CFG_PB BIT(7)
34#define MPMC_STATIC_CFG_EW BIT(8)
35#define MPMC_STATIC_CFG_B BIT(19)
36#define MPMC_STATIC_CFG_P BIT(20)
37#define MPMC_STATIC_WAIT_WEN(n) (0x204 + 0x20 * n)
38#define MPMC_STATIC_WAIT_WEN_MAX 0x0f
39#define MPMC_STATIC_WAIT_OEN(n) (0x208 + 0x20 * n)
40#define MPMC_STATIC_WAIT_OEN_MAX 0x0f
41#define MPMC_STATIC_WAIT_RD(n) (0x20c + 0x20 * n)
42#define MPMC_STATIC_WAIT_RD_MAX 0x1f
43#define MPMC_STATIC_WAIT_PAGE(n) (0x210 + 0x20 * n)
44#define MPMC_STATIC_WAIT_PAGE_MAX 0x1f
45#define MPMC_STATIC_WAIT_WR(n) (0x214 + 0x20 * n)
46#define MPMC_STATIC_WAIT_WR_MAX 0x1f
47#define MPMC_STATIC_WAIT_TURN(n) (0x218 + 0x20 * n)
48#define MPMC_STATIC_WAIT_TURN_MAX 0x0f
49
50/* Maximum number of static chip selects */
51#define PL172_MAX_CS 4
52
53struct pl172_data {
54 void __iomem *base;
55 unsigned long rate;
56 struct clk *clk;
57};
58
59static int pl172_timing_prop(struct amba_device *adev,
60 const struct device_node *np, const char *name,
61 u32 reg_offset, u32 max, int start)
62{
63 struct pl172_data *pl172 = amba_get_drvdata(adev);
64 int cycles;
65 u32 val;
66
67 if (!of_property_read_u32(np, name, &val)) {
68 cycles = DIV_ROUND_UP(val * pl172->rate, NSEC_PER_MSEC) - start;
69 if (cycles < 0) {
70 cycles = 0;
71 } else if (cycles > max) {
72 dev_err(&adev->dev, "%s timing too tight\n", name);
73 return -EINVAL;
74 }
75
76 writel(cycles, pl172->base + reg_offset);
77 }
78
79 dev_dbg(&adev->dev, "%s: %u cycle(s)\n", name, start +
80 readl(pl172->base + reg_offset));
81
82 return 0;
83}
84
85static int pl172_setup_static(struct amba_device *adev,
86 struct device_node *np, u32 cs)
87{
88 struct pl172_data *pl172 = amba_get_drvdata(adev);
89 u32 cfg;
90 int ret;
91
92 /* MPMC static memory configuration */
93 if (!of_property_read_u32(np, "mpmc,memory-width", &cfg)) {
94 if (cfg == 8) {
95 cfg = MPMC_STATIC_CFG_MW_8BIT;
96 } else if (cfg == 16) {
97 cfg = MPMC_STATIC_CFG_MW_16BIT;
98 } else if (cfg == 32) {
99 cfg = MPMC_STATIC_CFG_MW_32BIT;
100 } else {
101 dev_err(&adev->dev, "invalid memory width cs%u\n", cs);
102 return -EINVAL;
103 }
104 } else {
105 dev_err(&adev->dev, "memory-width property required\n");
106 return -EINVAL;
107 }
108
109 if (of_property_read_bool(np, "mpmc,async-page-mode"))
110 cfg |= MPMC_STATIC_CFG_PM;
111
112 if (of_property_read_bool(np, "mpmc,cs-active-high"))
113 cfg |= MPMC_STATIC_CFG_PC;
114
115 if (of_property_read_bool(np, "mpmc,byte-lane-low"))
116 cfg |= MPMC_STATIC_CFG_PB;
117
118 if (of_property_read_bool(np, "mpmc,extended-wait"))
119 cfg |= MPMC_STATIC_CFG_EW;
120
121 if (of_property_read_bool(np, "mpmc,buffer-enable"))
122 cfg |= MPMC_STATIC_CFG_B;
123
124 if (of_property_read_bool(np, "mpmc,write-protect"))
125 cfg |= MPMC_STATIC_CFG_P;
126
127 writel(cfg, pl172->base + MPMC_STATIC_CFG(cs));
128 dev_dbg(&adev->dev, "mpmc static config cs%u: 0x%08x\n", cs, cfg);
129
130 /* MPMC static memory timing */
131 ret = pl172_timing_prop(adev, np, "mpmc,write-enable-delay",
132 MPMC_STATIC_WAIT_WEN(cs),
133 MPMC_STATIC_WAIT_WEN_MAX, 1);
134 if (ret)
135 goto fail;
136
137 ret = pl172_timing_prop(adev, np, "mpmc,output-enable-delay",
138 MPMC_STATIC_WAIT_OEN(cs),
139 MPMC_STATIC_WAIT_OEN_MAX, 0);
140 if (ret)
141 goto fail;
142
143 ret = pl172_timing_prop(adev, np, "mpmc,read-access-delay",
144 MPMC_STATIC_WAIT_RD(cs),
145 MPMC_STATIC_WAIT_RD_MAX, 1);
146 if (ret)
147 goto fail;
148
149 ret = pl172_timing_prop(adev, np, "mpmc,page-mode-read-delay",
150 MPMC_STATIC_WAIT_PAGE(cs),
151 MPMC_STATIC_WAIT_PAGE_MAX, 1);
152 if (ret)
153 goto fail;
154
155 ret = pl172_timing_prop(adev, np, "mpmc,write-access-delay",
156 MPMC_STATIC_WAIT_WR(cs),
157 MPMC_STATIC_WAIT_WR_MAX, 2);
158 if (ret)
159 goto fail;
160
161 ret = pl172_timing_prop(adev, np, "mpmc,turn-round-delay",
162 MPMC_STATIC_WAIT_TURN(cs),
163 MPMC_STATIC_WAIT_TURN_MAX, 1);
164 if (ret)
165 goto fail;
166
167 return 0;
168fail:
169 dev_err(&adev->dev, "failed to configure cs%u\n", cs);
170 return ret;
171}
172
173static int pl172_parse_cs_config(struct amba_device *adev,
174 struct device_node *np)
175{
176 u32 cs;
177
178 if (!of_property_read_u32(np, "mpmc,cs", &cs)) {
179 if (cs >= PL172_MAX_CS) {
180 dev_err(&adev->dev, "cs%u invalid\n", cs);
181 return -EINVAL;
182 }
183
184 return pl172_setup_static(adev, np, cs);
185 }
186
187 dev_err(&adev->dev, "cs property required\n");
188
189 return -EINVAL;
190}
191
192static const char * const pl172_revisions[] = {"r1", "r2", "r2p3", "r2p4"};
193
194static int pl172_probe(struct amba_device *adev, const struct amba_id *id)
195{
196 struct device_node *child_np, *np = adev->dev.of_node;
197 struct device *dev = &adev->dev;
198 static const char *rev = "?";
199 struct pl172_data *pl172;
200 int ret;
201
202 if (amba_part(adev) == 0x172) {
203 if (amba_rev(adev) < ARRAY_SIZE(pl172_revisions))
204 rev = pl172_revisions[amba_rev(adev)];
205 }
206
207 dev_info(dev, "ARM PL%x revision %s\n", amba_part(adev), rev);
208
209 pl172 = devm_kzalloc(dev, sizeof(*pl172), GFP_KERNEL);
210 if (!pl172)
211 return -ENOMEM;
212
213 pl172->clk = devm_clk_get(dev, "mpmcclk");
214 if (IS_ERR(pl172->clk)) {
215 dev_err(dev, "no mpmcclk provided clock\n");
216 return PTR_ERR(pl172->clk);
217 }
218
219 ret = clk_prepare_enable(pl172->clk);
220 if (ret) {
221 dev_err(dev, "unable to mpmcclk enable clock\n");
222 return ret;
223 }
224
225 pl172->rate = clk_get_rate(pl172->clk) / MSEC_PER_SEC;
226 if (!pl172->rate) {
227 dev_err(dev, "unable to get mpmcclk clock rate\n");
228 ret = -EINVAL;
229 goto err_clk_enable;
230 }
231
232 ret = amba_request_regions(adev, NULL);
233 if (ret) {
234 dev_err(dev, "unable to request AMBA regions\n");
235 goto err_clk_enable;
236 }
237
238 pl172->base = devm_ioremap(dev, adev->res.start,
239 resource_size(&adev->res));
240 if (!pl172->base) {
241 dev_err(dev, "ioremap failed\n");
242 ret = -ENOMEM;
243 goto err_no_ioremap;
244 }
245
246 amba_set_drvdata(adev, pl172);
247
248 /*
249 * Loop through each child node, which represent a chip select, and
250 * configure parameters and timing. If successful; populate devices
251 * under that node.
252 */
253 for_each_available_child_of_node(np, child_np) {
254 ret = pl172_parse_cs_config(adev, child_np);
255 if (ret)
256 continue;
257
0ff818ef 258 of_platform_populate(child_np, NULL, NULL, dev);
17c50b70
JE
259 }
260
261 return 0;
262
263err_no_ioremap:
264 amba_release_regions(adev);
265err_clk_enable:
266 clk_disable_unprepare(pl172->clk);
267 return ret;
268}
269
270static int pl172_remove(struct amba_device *adev)
271{
272 struct pl172_data *pl172 = amba_get_drvdata(adev);
273
274 clk_disable_unprepare(pl172->clk);
275 amba_release_regions(adev);
276
277 return 0;
278}
279
280static const struct amba_id pl172_ids[] = {
281 {
282 .id = 0x07341172,
283 .mask = 0xffffffff,
284 },
285 { 0, 0 },
286};
287MODULE_DEVICE_TABLE(amba, pl172_ids);
288
289static struct amba_driver pl172_driver = {
290 .drv = {
291 .name = "memory-pl172",
292 },
293 .probe = pl172_probe,
294 .remove = pl172_remove,
295 .id_table = pl172_ids,
296};
297module_amba_driver(pl172_driver);
298
299MODULE_AUTHOR("Joachim Eastwood <manabian@gmail.com>");
300MODULE_DESCRIPTION("PL172 Memory Controller Driver");
301MODULE_LICENSE("GPL v2");