1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Copyright (C) 2019 MediaTek Inc. All Rights Reserved.
4 *
5 * Author: Weijie Gao <weijie.gao@mediatek.com>
6 */
7
8 #include <common.h>
9 #include <clk.h>
10 #include <dm.h>
11 #include <errno.h>
12 #include <spi.h>
13 #include <spi-mem.h>
14 #include <stdbool.h>
15 #include <watchdog.h>
16 #include <dm/pinctrl.h>
17 #include <linux/bitops.h>
18 #include <linux/io.h>
19 #include <linux/iopoll.h>
20
21 #define SNFI_MAC_CTL 0x500
22 #define MAC_XIO_SEL BIT(4)
23 #define SF_MAC_EN BIT(3)
24 #define SF_TRIG BIT(2)
25 #define WIP_READY BIT(1)
26 #define WIP BIT(0)
27
28 #define SNFI_MAC_OUTL 0x504
29 #define SNFI_MAC_INL 0x508
30
31 #define SNFI_MISC_CTL 0x538
32 #define SW_RST BIT(28)
33 #define FIFO_RD_LTC_SHIFT 25
34 #define FIFO_RD_LTC GENMASK(26, 25)
35 #define LATCH_LAT_SHIFT 8
36 #define LATCH_LAT GENMASK(9, 8)
37 #define CS_DESELECT_CYC_SHIFT 0
38 #define CS_DESELECT_CYC GENMASK(4, 0)
39
40 #define SNF_STA_CTL1 0x550
41 #define SPI_STATE GENMASK(3, 0)
42
43 #define SNFI_GPRAM_OFFSET 0x800
44 #define SNFI_GPRAM_SIZE 0x80
45
46 #define SNFI_POLL_INTERVAL 500000
47 #define SNFI_RST_POLL_INTERVAL 1000000
48
49 struct mtk_snfi_priv {
50 void __iomem *base;
51
52 struct clk nfi_clk;
53 struct clk pad_clk;
54 };
55
mtk_snfi_adjust_op_size(struct spi_slave * slave,struct spi_mem_op * op)56 static int mtk_snfi_adjust_op_size(struct spi_slave *slave,
57 struct spi_mem_op *op)
58 {
59 u32 nbytes;
60
61 /*
62 * When there is input data, it will be appended after the output
63 * data in the GPRAM. So the total size of either pure output data
64 * or the output+input data must not exceed the GPRAM size.
65 */
66
67 nbytes = sizeof(op->cmd.opcode) + op->addr.nbytes +
68 op->dummy.nbytes;
69
70 if (nbytes + op->data.nbytes <= SNFI_GPRAM_SIZE)
71 return 0;
72
73 if (nbytes >= SNFI_GPRAM_SIZE)
74 return -ENOTSUPP;
75
76 op->data.nbytes = SNFI_GPRAM_SIZE - nbytes;
77
78 return 0;
79 }
80
mtk_snfi_supports_op(struct spi_slave * slave,const struct spi_mem_op * op)81 static bool mtk_snfi_supports_op(struct spi_slave *slave,
82 const struct spi_mem_op *op)
83 {
84 if (op->cmd.buswidth > 1 || op->addr.buswidth > 1 ||
85 op->dummy.buswidth > 1 || op->data.buswidth > 1)
86 return false;
87
88 return true;
89 }
90
mtk_snfi_mac_trigger(struct mtk_snfi_priv * priv,struct udevice * bus,u32 outlen,u32 inlen)91 static int mtk_snfi_mac_trigger(struct mtk_snfi_priv *priv,
92 struct udevice *bus, u32 outlen, u32 inlen)
93 {
94 int ret;
95 u32 val;
96
97 #ifdef CONFIG_PINCTRL
98 pinctrl_select_state(bus, "snfi");
99 #endif
100
101 writel(SF_MAC_EN, priv->base + SNFI_MAC_CTL);
102 writel(outlen, priv->base + SNFI_MAC_OUTL);
103 writel(inlen, priv->base + SNFI_MAC_INL);
104
105 writel(SF_MAC_EN | SF_TRIG, priv->base + SNFI_MAC_CTL);
106
107 ret = readl_poll_timeout(priv->base + SNFI_MAC_CTL, val,
108 val & WIP_READY, SNFI_POLL_INTERVAL);
109 if (ret) {
110 printf("%s: timed out waiting for WIP_READY\n", __func__);
111 goto cleanup;
112 }
113
114 ret = readl_poll_timeout(priv->base + SNFI_MAC_CTL, val,
115 !(val & WIP), SNFI_POLL_INTERVAL);
116 if (ret)
117 printf("%s: timed out waiting for WIP cleared\n", __func__);
118
119 writel(0, priv->base + SNFI_MAC_CTL);
120
121 cleanup:
122 #ifdef CONFIG_PINCTRL
123 pinctrl_select_state(bus, "default");
124 #endif
125
126 return ret;
127 }
128
mtk_snfi_mac_reset(struct mtk_snfi_priv * priv)129 static int mtk_snfi_mac_reset(struct mtk_snfi_priv *priv)
130 {
131 int ret;
132 u32 val;
133
134 setbits_32(priv->base + SNFI_MISC_CTL, SW_RST);
135
136 ret = readl_poll_timeout(priv->base + SNF_STA_CTL1, val,
137 !(val & SPI_STATE), SNFI_POLL_INTERVAL);
138 if (ret)
139 printf("%s: failed to reset snfi mac\n", __func__);
140
141 writel((2 << FIFO_RD_LTC_SHIFT) |
142 (10 << CS_DESELECT_CYC_SHIFT),
143 priv->base + SNFI_MISC_CTL);
144
145 return ret;
146 }
147
mtk_snfi_copy_to_gpram(struct mtk_snfi_priv * priv,const void * data,size_t len)148 static void mtk_snfi_copy_to_gpram(struct mtk_snfi_priv *priv,
149 const void *data, size_t len)
150 {
151 void __iomem *gpram = priv->base + SNFI_GPRAM_OFFSET;
152 size_t i, n = (len + sizeof(u32) - 1) / sizeof(u32);
153 const u32 *buff = data;
154
155 /*
156 * The output data will always be copied to the beginning of
157 * the GPRAM. Uses word write for better performace.
158 *
159 * Trailing bytes in the last word are not cared.
160 */
161
162 for (i = 0; i < n; i++)
163 writel(buff[i], gpram + i * sizeof(u32));
164 }
165
mtk_snfi_copy_from_gpram(struct mtk_snfi_priv * priv,u8 * cache,void * data,size_t pos,size_t len)166 static void mtk_snfi_copy_from_gpram(struct mtk_snfi_priv *priv, u8 *cache,
167 void *data, size_t pos, size_t len)
168 {
169 void __iomem *gpram = priv->base + SNFI_GPRAM_OFFSET;
170 u32 *buff = (u32 *)cache;
171 size_t i, off, end;
172
173 /* Start position in the buffer */
174 off = pos & (sizeof(u32) - 1);
175
176 /* End position for copy */
177 end = (len + pos + sizeof(u32) - 1) & (~(sizeof(u32) - 1));
178
179 /* Start position for copy */
180 pos &= ~(sizeof(u32) - 1);
181
182 /*
183 * Read aligned data from GPRAM to buffer first.
184 * Uses word read for better performace.
185 */
186 i = 0;
187 while (pos < end) {
188 buff[i++] = readl(gpram + pos);
189 pos += sizeof(u32);
190 }
191
192 /* Copy rx data */
193 memcpy(data, cache + off, len);
194 }
195
mtk_snfi_exec_op(struct spi_slave * slave,const struct spi_mem_op * op)196 static int mtk_snfi_exec_op(struct spi_slave *slave,
197 const struct spi_mem_op *op)
198 {
199 struct udevice *bus = dev_get_parent(slave->dev);
200 struct mtk_snfi_priv *priv = dev_get_priv(bus);
201 u8 gpram_cache[SNFI_GPRAM_SIZE];
202 u32 i, len = 0, inlen = 0;
203 int addr_sh;
204 int ret;
205
206 WATCHDOG_RESET();
207
208 ret = mtk_snfi_mac_reset(priv);
209 if (ret)
210 return ret;
211
212 /* Put opcode */
213 gpram_cache[len++] = op->cmd.opcode;
214
215 /* Put address */
216 addr_sh = (op->addr.nbytes - 1) * 8;
217 while (addr_sh >= 0) {
218 gpram_cache[len++] = (op->addr.val >> addr_sh) & 0xff;
219 addr_sh -= 8;
220 }
221
222 /* Put dummy bytes */
223 for (i = 0; i < op->dummy.nbytes; i++)
224 gpram_cache[len++] = 0;
225
226 /* Put output data */
227 if (op->data.nbytes && op->data.dir == SPI_MEM_DATA_OUT) {
228 memcpy(gpram_cache + len, op->data.buf.out, op->data.nbytes);
229 len += op->data.nbytes;
230 }
231
232 /* Copy final output data to GPRAM */
233 mtk_snfi_copy_to_gpram(priv, gpram_cache, len);
234
235 /* Start one SPI transaction */
236 if (op->data.nbytes && op->data.dir == SPI_MEM_DATA_IN)
237 inlen = op->data.nbytes;
238
239 ret = mtk_snfi_mac_trigger(priv, bus, len, inlen);
240 if (ret)
241 return ret;
242
243 /* Copy input data from GPRAM */
244 if (inlen)
245 mtk_snfi_copy_from_gpram(priv, gpram_cache, op->data.buf.in,
246 len, inlen);
247
248 return 0;
249 }
250
mtk_snfi_spi_probe(struct udevice * bus)251 static int mtk_snfi_spi_probe(struct udevice *bus)
252 {
253 struct mtk_snfi_priv *priv = dev_get_priv(bus);
254 int ret;
255
256 priv->base = dev_read_addr_ptr(bus);
257 if (!priv->base)
258 return -EINVAL;
259
260 ret = clk_get_by_name(bus, "nfi_clk", &priv->nfi_clk);
261 if (ret < 0)
262 return ret;
263
264 ret = clk_get_by_name(bus, "pad_clk", &priv->pad_clk);
265 if (ret < 0)
266 return ret;
267
268 clk_enable(&priv->nfi_clk);
269 clk_enable(&priv->pad_clk);
270
271 return 0;
272 }
273
mtk_snfi_set_speed(struct udevice * bus,uint speed)274 static int mtk_snfi_set_speed(struct udevice *bus, uint speed)
275 {
276 /*
277 * The SNFI does not have a bus clock divider.
278 * The bus clock is set in dts (pad_clk, UNIVPLL2_D8 = 50MHz).
279 */
280
281 return 0;
282 }
283
mtk_snfi_set_mode(struct udevice * bus,uint mode)284 static int mtk_snfi_set_mode(struct udevice *bus, uint mode)
285 {
286 /* The SNFI supports only mode 0 */
287
288 if (mode)
289 return -EINVAL;
290
291 return 0;
292 }
293
294 static const struct spi_controller_mem_ops mtk_snfi_mem_ops = {
295 .adjust_op_size = mtk_snfi_adjust_op_size,
296 .supports_op = mtk_snfi_supports_op,
297 .exec_op = mtk_snfi_exec_op,
298 };
299
300 static const struct dm_spi_ops mtk_snfi_spi_ops = {
301 .mem_ops = &mtk_snfi_mem_ops,
302 .set_speed = mtk_snfi_set_speed,
303 .set_mode = mtk_snfi_set_mode,
304 };
305
306 static const struct udevice_id mtk_snfi_spi_ids[] = {
307 { .compatible = "mediatek,mtk-snfi-spi" },
308 { }
309 };
310
311 U_BOOT_DRIVER(mtk_snfi_spi) = {
312 .name = "mtk_snfi_spi",
313 .id = UCLASS_SPI,
314 .of_match = mtk_snfi_spi_ids,
315 .ops = &mtk_snfi_spi_ops,
316 .priv_auto = sizeof(struct mtk_snfi_priv),
317 .probe = mtk_snfi_spi_probe,
318 };
319