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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Memory-mapped interface driver for DW SPI Core
4 *
5 * Copyright (c) 2010, Octasic semiconductor.
6 */
7
8#include <linux/clk.h>
9#include <linux/err.h>
10#include <linux/platform_device.h>
11#include <linux/pm_runtime.h>
12#include <linux/slab.h>
13#include <linux/spi/spi.h>
14#include <linux/scatterlist.h>
15#include <linux/mfd/syscon.h>
16#include <linux/module.h>
17#include <linux/of.h>
18#include <linux/of_platform.h>
19#include <linux/acpi.h>
20#include <linux/property.h>
21#include <linux/regmap.h>
22#include <linux/reset.h>
23
24#include "spi-dw.h"
25
26#define DRIVER_NAME "dw_spi_mmio"
27
28struct dw_spi_mmio {
29 struct dw_spi dws;
30 struct clk *clk;
31 struct clk *pclk;
32 void *priv;
33 struct reset_control *rstc;
34};
35
36#define MSCC_CPU_SYSTEM_CTRL_GENERAL_CTRL 0x24
37#define OCELOT_IF_SI_OWNER_OFFSET 4
38#define JAGUAR2_IF_SI_OWNER_OFFSET 6
39#define MSCC_IF_SI_OWNER_MASK GENMASK(1, 0)
40#define MSCC_IF_SI_OWNER_SISL 0
41#define MSCC_IF_SI_OWNER_SIBM 1
42#define MSCC_IF_SI_OWNER_SIMC 2
43
44#define MSCC_SPI_MST_SW_MODE 0x14
45#define MSCC_SPI_MST_SW_MODE_SW_PIN_CTRL_MODE BIT(13)
46#define MSCC_SPI_MST_SW_MODE_SW_SPI_CS(x) (x << 5)
47
48#define SPARX5_FORCE_ENA 0xa4
49#define SPARX5_FORCE_VAL 0xa8
50
51struct dw_spi_mscc {
52 struct regmap *syscon;
53 void __iomem *spi_mst; /* Not sparx5 */
54};
55
56/*
57 * The Designware SPI controller (referred to as master in the documentation)
58 * automatically deasserts chip select when the tx fifo is empty. The chip
59 * selects then needs to be either driven as GPIOs or, for the first 4 using
60 * the SPI boot controller registers. the final chip select is an OR gate
61 * between the Designware SPI controller and the SPI boot controller.
62 */
63static void dw_spi_mscc_set_cs(struct spi_device *spi, bool enable)
64{
65 struct dw_spi *dws = spi_master_get_devdata(spi->master);
66 struct dw_spi_mmio *dwsmmio = container_of(dws, struct dw_spi_mmio, dws);
67 struct dw_spi_mscc *dwsmscc = dwsmmio->priv;
68 u32 cs = spi->chip_select;
69
70 if (cs < 4) {
71 u32 sw_mode = MSCC_SPI_MST_SW_MODE_SW_PIN_CTRL_MODE;
72
73 if (!enable)
74 sw_mode |= MSCC_SPI_MST_SW_MODE_SW_SPI_CS(BIT(cs));
75
76 writel(sw_mode, dwsmscc->spi_mst + MSCC_SPI_MST_SW_MODE);
77 }
78
79 dw_spi_set_cs(spi, enable);
80}
81
82static int dw_spi_mscc_init(struct platform_device *pdev,
83 struct dw_spi_mmio *dwsmmio,
84 const char *cpu_syscon, u32 if_si_owner_offset)
85{
86 struct dw_spi_mscc *dwsmscc;
87
88 dwsmscc = devm_kzalloc(&pdev->dev, sizeof(*dwsmscc), GFP_KERNEL);
89 if (!dwsmscc)
90 return -ENOMEM;
91
92 dwsmscc->spi_mst = devm_platform_ioremap_resource(pdev, 1);
93 if (IS_ERR(dwsmscc->spi_mst)) {
94 dev_err(&pdev->dev, "SPI_MST region map failed\n");
95 return PTR_ERR(dwsmscc->spi_mst);
96 }
97
98 dwsmscc->syscon = syscon_regmap_lookup_by_compatible(cpu_syscon);
99 if (IS_ERR(dwsmscc->syscon))
100 return PTR_ERR(dwsmscc->syscon);
101
102 /* Deassert all CS */
103 writel(0, dwsmscc->spi_mst + MSCC_SPI_MST_SW_MODE);
104
105 /* Select the owner of the SI interface */
106 regmap_update_bits(dwsmscc->syscon, MSCC_CPU_SYSTEM_CTRL_GENERAL_CTRL,
107 MSCC_IF_SI_OWNER_MASK << if_si_owner_offset,
108 MSCC_IF_SI_OWNER_SIMC << if_si_owner_offset);
109
110 dwsmmio->dws.set_cs = dw_spi_mscc_set_cs;
111 dwsmmio->priv = dwsmscc;
112
113 return 0;
114}
115
116static int dw_spi_mscc_ocelot_init(struct platform_device *pdev,
117 struct dw_spi_mmio *dwsmmio)
118{
119 return dw_spi_mscc_init(pdev, dwsmmio, "mscc,ocelot-cpu-syscon",
120 OCELOT_IF_SI_OWNER_OFFSET);
121}
122
123static int dw_spi_mscc_jaguar2_init(struct platform_device *pdev,
124 struct dw_spi_mmio *dwsmmio)
125{
126 return dw_spi_mscc_init(pdev, dwsmmio, "mscc,jaguar2-cpu-syscon",
127 JAGUAR2_IF_SI_OWNER_OFFSET);
128}
129
130/*
131 * The Designware SPI controller (referred to as master in the
132 * documentation) automatically deasserts chip select when the tx fifo
133 * is empty. The chip selects then needs to be driven by a CS override
134 * register. enable is an active low signal.
135 */
136static void dw_spi_sparx5_set_cs(struct spi_device *spi, bool enable)
137{
138 struct dw_spi *dws = spi_master_get_devdata(spi->master);
139 struct dw_spi_mmio *dwsmmio = container_of(dws, struct dw_spi_mmio, dws);
140 struct dw_spi_mscc *dwsmscc = dwsmmio->priv;
141 u8 cs = spi->chip_select;
142
143 if (!enable) {
144 /* CS override drive enable */
145 regmap_write(dwsmscc->syscon, SPARX5_FORCE_ENA, 1);
146 /* Now set CSx enabled */
147 regmap_write(dwsmscc->syscon, SPARX5_FORCE_VAL, ~BIT(cs));
148 /* Allow settle */
149 usleep_range(1, 5);
150 } else {
151 /* CS value */
152 regmap_write(dwsmscc->syscon, SPARX5_FORCE_VAL, ~0);
153 /* Allow settle */
154 usleep_range(1, 5);
155 /* CS override drive disable */
156 regmap_write(dwsmscc->syscon, SPARX5_FORCE_ENA, 0);
157 }
158
159 dw_spi_set_cs(spi, enable);
160}
161
162static int dw_spi_mscc_sparx5_init(struct platform_device *pdev,
163 struct dw_spi_mmio *dwsmmio)
164{
165 const char *syscon_name = "microchip,sparx5-cpu-syscon";
166 struct device *dev = &pdev->dev;
167 struct dw_spi_mscc *dwsmscc;
168
169 if (!IS_ENABLED(CONFIG_SPI_MUX)) {
170 dev_err(dev, "This driver needs CONFIG_SPI_MUX\n");
171 return -EOPNOTSUPP;
172 }
173
174 dwsmscc = devm_kzalloc(dev, sizeof(*dwsmscc), GFP_KERNEL);
175 if (!dwsmscc)
176 return -ENOMEM;
177
178 dwsmscc->syscon =
179 syscon_regmap_lookup_by_compatible(syscon_name);
180 if (IS_ERR(dwsmscc->syscon)) {
181 dev_err(dev, "No syscon map %s\n", syscon_name);
182 return PTR_ERR(dwsmscc->syscon);
183 }
184
185 dwsmmio->dws.set_cs = dw_spi_sparx5_set_cs;
186 dwsmmio->priv = dwsmscc;
187
188 return 0;
189}
190
191static int dw_spi_alpine_init(struct platform_device *pdev,
192 struct dw_spi_mmio *dwsmmio)
193{
194 dwsmmio->dws.caps = DW_SPI_CAP_CS_OVERRIDE;
195
196 return 0;
197}
198
199static int dw_spi_pssi_init(struct platform_device *pdev,
200 struct dw_spi_mmio *dwsmmio)
201{
202 dw_spi_dma_setup_generic(&dwsmmio->dws);
203
204 return 0;
205}
206
207static int dw_spi_hssi_init(struct platform_device *pdev,
208 struct dw_spi_mmio *dwsmmio)
209{
210 dwsmmio->dws.ip = DW_HSSI_ID;
211
212 dw_spi_dma_setup_generic(&dwsmmio->dws);
213
214 return 0;
215}
216
217static int dw_spi_intel_init(struct platform_device *pdev,
218 struct dw_spi_mmio *dwsmmio)
219{
220 dwsmmio->dws.ip = DW_HSSI_ID;
221
222 return 0;
223}
224
225static int dw_spi_canaan_k210_init(struct platform_device *pdev,
226 struct dw_spi_mmio *dwsmmio)
227{
228 /*
229 * The Canaan Kendryte K210 SoC DW apb_ssi v4 spi controller is
230 * documented to have a 32 word deep TX and RX FIFO, which
231 * spi_hw_init() detects. However, when the RX FIFO is filled up to
232 * 32 entries (RXFLR = 32), an RX FIFO overrun error occurs. Avoid this
233 * problem by force setting fifo_len to 31.
234 */
235 dwsmmio->dws.fifo_len = 31;
236
237 return 0;
238}
239
240static int dw_spi_mmio_probe(struct platform_device *pdev)
241{
242 int (*init_func)(struct platform_device *pdev,
243 struct dw_spi_mmio *dwsmmio);
244 struct dw_spi_mmio *dwsmmio;
245 struct resource *mem;
246 struct dw_spi *dws;
247 int ret;
248 int num_cs;
249
250 dwsmmio = devm_kzalloc(&pdev->dev, sizeof(struct dw_spi_mmio),
251 GFP_KERNEL);
252 if (!dwsmmio)
253 return -ENOMEM;
254
255 dws = &dwsmmio->dws;
256
257 /* Get basic io resource and map it */
258 dws->regs = devm_platform_get_and_ioremap_resource(pdev, 0, &mem);
259 if (IS_ERR(dws->regs))
260 return PTR_ERR(dws->regs);
261
262 dws->paddr = mem->start;
263
264 dws->irq = platform_get_irq(pdev, 0);
265 if (dws->irq < 0)
266 return dws->irq; /* -ENXIO */
267
268 dwsmmio->clk = devm_clk_get(&pdev->dev, NULL);
269 if (IS_ERR(dwsmmio->clk))
270 return PTR_ERR(dwsmmio->clk);
271 ret = clk_prepare_enable(dwsmmio->clk);
272 if (ret)
273 return ret;
274
275 /* Optional clock needed to access the registers */
276 dwsmmio->pclk = devm_clk_get_optional(&pdev->dev, "pclk");
277 if (IS_ERR(dwsmmio->pclk)) {
278 ret = PTR_ERR(dwsmmio->pclk);
279 goto out_clk;
280 }
281 ret = clk_prepare_enable(dwsmmio->pclk);
282 if (ret)
283 goto out_clk;
284
285 /* find an optional reset controller */
286 dwsmmio->rstc = devm_reset_control_get_optional_exclusive(&pdev->dev, "spi");
287 if (IS_ERR(dwsmmio->rstc)) {
288 ret = PTR_ERR(dwsmmio->rstc);
289 goto out_clk;
290 }
291 reset_control_deassert(dwsmmio->rstc);
292
293 dws->bus_num = pdev->id;
294
295 dws->max_freq = clk_get_rate(dwsmmio->clk);
296
297 device_property_read_u32(&pdev->dev, "reg-io-width", &dws->reg_io_width);
298
299 num_cs = 4;
300
301 device_property_read_u32(&pdev->dev, "num-cs", &num_cs);
302
303 dws->num_cs = num_cs;
304
305 init_func = device_get_match_data(&pdev->dev);
306 if (init_func) {
307 ret = init_func(pdev, dwsmmio);
308 if (ret)
309 goto out;
310 }
311
312 pm_runtime_enable(&pdev->dev);
313
314 ret = dw_spi_add_host(&pdev->dev, dws);
315 if (ret)
316 goto out;
317
318 platform_set_drvdata(pdev, dwsmmio);
319 return 0;
320
321out:
322 pm_runtime_disable(&pdev->dev);
323 clk_disable_unprepare(dwsmmio->pclk);
324out_clk:
325 clk_disable_unprepare(dwsmmio->clk);
326 reset_control_assert(dwsmmio->rstc);
327
328 return ret;
329}
330
331static int dw_spi_mmio_remove(struct platform_device *pdev)
332{
333 struct dw_spi_mmio *dwsmmio = platform_get_drvdata(pdev);
334
335 dw_spi_remove_host(&dwsmmio->dws);
336 pm_runtime_disable(&pdev->dev);
337 clk_disable_unprepare(dwsmmio->pclk);
338 clk_disable_unprepare(dwsmmio->clk);
339 reset_control_assert(dwsmmio->rstc);
340
341 return 0;
342}
343
344static const struct of_device_id dw_spi_mmio_of_match[] = {
345 { .compatible = "snps,dw-apb-ssi", .data = dw_spi_pssi_init},
346 { .compatible = "mscc,ocelot-spi", .data = dw_spi_mscc_ocelot_init},
347 { .compatible = "mscc,jaguar2-spi", .data = dw_spi_mscc_jaguar2_init},
348 { .compatible = "amazon,alpine-dw-apb-ssi", .data = dw_spi_alpine_init},
349 { .compatible = "renesas,rzn1-spi", .data = dw_spi_pssi_init},
350 { .compatible = "snps,dwc-ssi-1.01a", .data = dw_spi_hssi_init},
351 { .compatible = "intel,keembay-ssi", .data = dw_spi_intel_init},
352 { .compatible = "intel,thunderbay-ssi", .data = dw_spi_intel_init},
353 { .compatible = "microchip,sparx5-spi", dw_spi_mscc_sparx5_init},
354 { .compatible = "canaan,k210-spi", dw_spi_canaan_k210_init},
355 { /* end of table */}
356};
357MODULE_DEVICE_TABLE(of, dw_spi_mmio_of_match);
358
359#ifdef CONFIG_ACPI
360static const struct acpi_device_id dw_spi_mmio_acpi_match[] = {
361 {"HISI0173", (kernel_ulong_t)dw_spi_pssi_init},
362 {},
363};
364MODULE_DEVICE_TABLE(acpi, dw_spi_mmio_acpi_match);
365#endif
366
367static struct platform_driver dw_spi_mmio_driver = {
368 .probe = dw_spi_mmio_probe,
369 .remove = dw_spi_mmio_remove,
370 .driver = {
371 .name = DRIVER_NAME,
372 .of_match_table = dw_spi_mmio_of_match,
373 .acpi_match_table = ACPI_PTR(dw_spi_mmio_acpi_match),
374 },
375};
376module_platform_driver(dw_spi_mmio_driver);
377
378MODULE_AUTHOR("Jean-Hugues Deschenes <jean-hugues.deschenes@octasic.com>");
379MODULE_DESCRIPTION("Memory-mapped I/O interface driver for DW SPI Core");
380MODULE_LICENSE("GPL v2");
381MODULE_IMPORT_NS(SPI_DW_CORE);
1/*
2 * Memory-mapped interface driver for DW SPI Core
3 *
4 * Copyright (c) 2010, Octasic semiconductor.
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms and conditions of the GNU General Public License,
8 * version 2, as published by the Free Software Foundation.
9 */
10
11#include <linux/clk.h>
12#include <linux/err.h>
13#include <linux/interrupt.h>
14#include <linux/platform_device.h>
15#include <linux/slab.h>
16#include <linux/spi/spi.h>
17#include <linux/scatterlist.h>
18
19#include "spi-dw.h"
20
21#define DRIVER_NAME "dw_spi_mmio"
22
23struct dw_spi_mmio {
24 struct dw_spi dws;
25 struct clk *clk;
26};
27
28static int __devinit dw_spi_mmio_probe(struct platform_device *pdev)
29{
30 struct dw_spi_mmio *dwsmmio;
31 struct dw_spi *dws;
32 struct resource *mem, *ioarea;
33 int ret;
34
35 dwsmmio = kzalloc(sizeof(struct dw_spi_mmio), GFP_KERNEL);
36 if (!dwsmmio) {
37 ret = -ENOMEM;
38 goto err_end;
39 }
40
41 dws = &dwsmmio->dws;
42
43 /* Get basic io resource and map it */
44 mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
45 if (!mem) {
46 dev_err(&pdev->dev, "no mem resource?\n");
47 ret = -EINVAL;
48 goto err_kfree;
49 }
50
51 ioarea = request_mem_region(mem->start, resource_size(mem),
52 pdev->name);
53 if (!ioarea) {
54 dev_err(&pdev->dev, "SPI region already claimed\n");
55 ret = -EBUSY;
56 goto err_kfree;
57 }
58
59 dws->regs = ioremap_nocache(mem->start, resource_size(mem));
60 if (!dws->regs) {
61 dev_err(&pdev->dev, "SPI region already mapped\n");
62 ret = -ENOMEM;
63 goto err_release_reg;
64 }
65
66 dws->irq = platform_get_irq(pdev, 0);
67 if (dws->irq < 0) {
68 dev_err(&pdev->dev, "no irq resource?\n");
69 ret = dws->irq; /* -ENXIO */
70 goto err_unmap;
71 }
72
73 dwsmmio->clk = clk_get(&pdev->dev, NULL);
74 if (IS_ERR(dwsmmio->clk)) {
75 ret = PTR_ERR(dwsmmio->clk);
76 goto err_irq;
77 }
78 clk_enable(dwsmmio->clk);
79
80 dws->parent_dev = &pdev->dev;
81 dws->bus_num = 0;
82 dws->num_cs = 4;
83 dws->max_freq = clk_get_rate(dwsmmio->clk);
84
85 ret = dw_spi_add_host(dws);
86 if (ret)
87 goto err_clk;
88
89 platform_set_drvdata(pdev, dwsmmio);
90 return 0;
91
92err_clk:
93 clk_disable(dwsmmio->clk);
94 clk_put(dwsmmio->clk);
95 dwsmmio->clk = NULL;
96err_irq:
97 free_irq(dws->irq, dws);
98err_unmap:
99 iounmap(dws->regs);
100err_release_reg:
101 release_mem_region(mem->start, resource_size(mem));
102err_kfree:
103 kfree(dwsmmio);
104err_end:
105 return ret;
106}
107
108static int __devexit dw_spi_mmio_remove(struct platform_device *pdev)
109{
110 struct dw_spi_mmio *dwsmmio = platform_get_drvdata(pdev);
111 struct resource *mem;
112
113 platform_set_drvdata(pdev, NULL);
114
115 clk_disable(dwsmmio->clk);
116 clk_put(dwsmmio->clk);
117 dwsmmio->clk = NULL;
118
119 free_irq(dwsmmio->dws.irq, &dwsmmio->dws);
120 dw_spi_remove_host(&dwsmmio->dws);
121 iounmap(dwsmmio->dws.regs);
122 kfree(dwsmmio);
123
124 mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
125 release_mem_region(mem->start, resource_size(mem));
126 return 0;
127}
128
129static struct platform_driver dw_spi_mmio_driver = {
130 .remove = __devexit_p(dw_spi_mmio_remove),
131 .driver = {
132 .name = DRIVER_NAME,
133 .owner = THIS_MODULE,
134 },
135};
136
137static int __init dw_spi_mmio_init(void)
138{
139 return platform_driver_probe(&dw_spi_mmio_driver, dw_spi_mmio_probe);
140}
141module_init(dw_spi_mmio_init);
142
143static void __exit dw_spi_mmio_exit(void)
144{
145 platform_driver_unregister(&dw_spi_mmio_driver);
146}
147module_exit(dw_spi_mmio_exit);
148
149MODULE_AUTHOR("Jean-Hugues Deschenes <jean-hugues.deschenes@octasic.com>");
150MODULE_DESCRIPTION("Memory-mapped I/O interface driver for DW SPI Core");
151MODULE_LICENSE("GPL v2");