1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Freescale MU used as MSI controller
4 *
5 * Copyright (c) 2018 Pengutronix, Oleksij Rempel <o.rempel@pengutronix.de>
6 * Copyright 2022 NXP
7 * Frank Li <Frank.Li@nxp.com>
8 * Peng Fan <peng.fan@nxp.com>
9 *
10 * Based on drivers/mailbox/imx-mailbox.c
11 */
12
13 #include <linux/clk.h>
14 #include <linux/irq.h>
15 #include <linux/irqchip.h>
16 #include <linux/irqchip/chained_irq.h>
17 #include <linux/irqdomain.h>
18 #include <linux/kernel.h>
19 #include <linux/module.h>
20 #include <linux/msi.h>
21 #include <linux/of_irq.h>
22 #include <linux/of_platform.h>
23 #include <linux/pm_runtime.h>
24 #include <linux/pm_domain.h>
25 #include <linux/spinlock.h>
26
27 #define IMX_MU_CHANS 4
28
29 enum imx_mu_xcr {
30 IMX_MU_GIER,
31 IMX_MU_GCR,
32 IMX_MU_TCR,
33 IMX_MU_RCR,
34 IMX_MU_xCR_MAX,
35 };
36
37 enum imx_mu_xsr {
38 IMX_MU_SR,
39 IMX_MU_GSR,
40 IMX_MU_TSR,
41 IMX_MU_RSR,
42 IMX_MU_xSR_MAX
43 };
44
45 enum imx_mu_type {
46 IMX_MU_V2 = BIT(1),
47 };
48
49 /* Receive Interrupt Enable */
50 #define IMX_MU_xCR_RIEn(data, x) ((data->cfg->type) & IMX_MU_V2 ? BIT(x) : BIT(24 + (3 - (x))))
51 #define IMX_MU_xSR_RFn(data, x) ((data->cfg->type) & IMX_MU_V2 ? BIT(x) : BIT(24 + (3 - (x))))
52
53 struct imx_mu_dcfg {
54 enum imx_mu_type type;
55 u32 xTR; /* Transmit Register0 */
56 u32 xRR; /* Receive Register0 */
57 u32 xSR[IMX_MU_xSR_MAX]; /* Status Registers */
58 u32 xCR[IMX_MU_xCR_MAX]; /* Control Registers */
59 };
60
61 struct imx_mu_msi {
62 raw_spinlock_t lock;
63 struct irq_domain *msi_domain;
64 void __iomem *regs;
65 phys_addr_t msiir_addr;
66 const struct imx_mu_dcfg *cfg;
67 unsigned long used;
68 struct clk *clk;
69 };
70
imx_mu_write(struct imx_mu_msi * msi_data,u32 val,u32 offs)71 static void imx_mu_write(struct imx_mu_msi *msi_data, u32 val, u32 offs)
72 {
73 iowrite32(val, msi_data->regs + offs);
74 }
75
imx_mu_read(struct imx_mu_msi * msi_data,u32 offs)76 static u32 imx_mu_read(struct imx_mu_msi *msi_data, u32 offs)
77 {
78 return ioread32(msi_data->regs + offs);
79 }
80
imx_mu_xcr_rmw(struct imx_mu_msi * msi_data,enum imx_mu_xcr type,u32 set,u32 clr)81 static u32 imx_mu_xcr_rmw(struct imx_mu_msi *msi_data, enum imx_mu_xcr type, u32 set, u32 clr)
82 {
83 unsigned long flags;
84 u32 val;
85
86 raw_spin_lock_irqsave(&msi_data->lock, flags);
87 val = imx_mu_read(msi_data, msi_data->cfg->xCR[type]);
88 val &= ~clr;
89 val |= set;
90 imx_mu_write(msi_data, val, msi_data->cfg->xCR[type]);
91 raw_spin_unlock_irqrestore(&msi_data->lock, flags);
92
93 return val;
94 }
95
imx_mu_msi_parent_mask_irq(struct irq_data * data)96 static void imx_mu_msi_parent_mask_irq(struct irq_data *data)
97 {
98 struct imx_mu_msi *msi_data = irq_data_get_irq_chip_data(data);
99
100 imx_mu_xcr_rmw(msi_data, IMX_MU_RCR, 0, IMX_MU_xCR_RIEn(msi_data, data->hwirq));
101 }
102
imx_mu_msi_parent_unmask_irq(struct irq_data * data)103 static void imx_mu_msi_parent_unmask_irq(struct irq_data *data)
104 {
105 struct imx_mu_msi *msi_data = irq_data_get_irq_chip_data(data);
106
107 imx_mu_xcr_rmw(msi_data, IMX_MU_RCR, IMX_MU_xCR_RIEn(msi_data, data->hwirq), 0);
108 }
109
imx_mu_msi_parent_ack_irq(struct irq_data * data)110 static void imx_mu_msi_parent_ack_irq(struct irq_data *data)
111 {
112 struct imx_mu_msi *msi_data = irq_data_get_irq_chip_data(data);
113
114 imx_mu_read(msi_data, msi_data->cfg->xRR + data->hwirq * 4);
115 }
116
117 static struct irq_chip imx_mu_msi_irq_chip = {
118 .name = "MU-MSI",
119 .irq_ack = irq_chip_ack_parent,
120 };
121
122 static struct msi_domain_ops imx_mu_msi_irq_ops = {
123 };
124
125 static struct msi_domain_info imx_mu_msi_domain_info = {
126 .flags = (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS),
127 .ops = &imx_mu_msi_irq_ops,
128 .chip = &imx_mu_msi_irq_chip,
129 };
130
imx_mu_msi_parent_compose_msg(struct irq_data * data,struct msi_msg * msg)131 static void imx_mu_msi_parent_compose_msg(struct irq_data *data,
132 struct msi_msg *msg)
133 {
134 struct imx_mu_msi *msi_data = irq_data_get_irq_chip_data(data);
135 u64 addr = msi_data->msiir_addr + 4 * data->hwirq;
136
137 msg->address_hi = upper_32_bits(addr);
138 msg->address_lo = lower_32_bits(addr);
139 msg->data = data->hwirq;
140 }
141
imx_mu_msi_parent_set_affinity(struct irq_data * irq_data,const struct cpumask * mask,bool force)142 static int imx_mu_msi_parent_set_affinity(struct irq_data *irq_data,
143 const struct cpumask *mask, bool force)
144 {
145 return -EINVAL;
146 }
147
148 static struct irq_chip imx_mu_msi_parent_chip = {
149 .name = "MU",
150 .irq_mask = imx_mu_msi_parent_mask_irq,
151 .irq_unmask = imx_mu_msi_parent_unmask_irq,
152 .irq_ack = imx_mu_msi_parent_ack_irq,
153 .irq_compose_msi_msg = imx_mu_msi_parent_compose_msg,
154 .irq_set_affinity = imx_mu_msi_parent_set_affinity,
155 };
156
imx_mu_msi_domain_irq_alloc(struct irq_domain * domain,unsigned int virq,unsigned int nr_irqs,void * args)157 static int imx_mu_msi_domain_irq_alloc(struct irq_domain *domain,
158 unsigned int virq,
159 unsigned int nr_irqs,
160 void *args)
161 {
162 struct imx_mu_msi *msi_data = domain->host_data;
163 unsigned long flags;
164 int pos, err = 0;
165
166 WARN_ON(nr_irqs != 1);
167
168 raw_spin_lock_irqsave(&msi_data->lock, flags);
169 pos = find_first_zero_bit(&msi_data->used, IMX_MU_CHANS);
170 if (pos < IMX_MU_CHANS)
171 __set_bit(pos, &msi_data->used);
172 else
173 err = -ENOSPC;
174 raw_spin_unlock_irqrestore(&msi_data->lock, flags);
175
176 if (err)
177 return err;
178
179 irq_domain_set_info(domain, virq, pos,
180 &imx_mu_msi_parent_chip, msi_data,
181 handle_edge_irq, NULL, NULL);
182 return 0;
183 }
184
imx_mu_msi_domain_irq_free(struct irq_domain * domain,unsigned int virq,unsigned int nr_irqs)185 static void imx_mu_msi_domain_irq_free(struct irq_domain *domain,
186 unsigned int virq, unsigned int nr_irqs)
187 {
188 struct irq_data *d = irq_domain_get_irq_data(domain, virq);
189 struct imx_mu_msi *msi_data = irq_data_get_irq_chip_data(d);
190 unsigned long flags;
191
192 raw_spin_lock_irqsave(&msi_data->lock, flags);
193 __clear_bit(d->hwirq, &msi_data->used);
194 raw_spin_unlock_irqrestore(&msi_data->lock, flags);
195 }
196
197 static const struct irq_domain_ops imx_mu_msi_domain_ops = {
198 .alloc = imx_mu_msi_domain_irq_alloc,
199 .free = imx_mu_msi_domain_irq_free,
200 };
201
imx_mu_msi_irq_handler(struct irq_desc * desc)202 static void imx_mu_msi_irq_handler(struct irq_desc *desc)
203 {
204 struct imx_mu_msi *msi_data = irq_desc_get_handler_data(desc);
205 struct irq_chip *chip = irq_desc_get_chip(desc);
206 u32 status;
207 int i;
208
209 status = imx_mu_read(msi_data, msi_data->cfg->xSR[IMX_MU_RSR]);
210
211 chained_irq_enter(chip, desc);
212 for (i = 0; i < IMX_MU_CHANS; i++) {
213 if (status & IMX_MU_xSR_RFn(msi_data, i))
214 generic_handle_domain_irq(msi_data->msi_domain, i);
215 }
216 chained_irq_exit(chip, desc);
217 }
218
imx_mu_msi_domains_init(struct imx_mu_msi * msi_data,struct device * dev)219 static int imx_mu_msi_domains_init(struct imx_mu_msi *msi_data, struct device *dev)
220 {
221 struct fwnode_handle *fwnodes = dev_fwnode(dev);
222 struct irq_domain *parent;
223
224 /* Initialize MSI domain parent */
225 parent = irq_domain_create_linear(fwnodes,
226 IMX_MU_CHANS,
227 &imx_mu_msi_domain_ops,
228 msi_data);
229 if (!parent) {
230 dev_err(dev, "failed to create IRQ domain\n");
231 return -ENOMEM;
232 }
233
234 irq_domain_update_bus_token(parent, DOMAIN_BUS_NEXUS);
235
236 msi_data->msi_domain = platform_msi_create_irq_domain(fwnodes,
237 &imx_mu_msi_domain_info,
238 parent);
239
240 if (!msi_data->msi_domain) {
241 dev_err(dev, "failed to create MSI domain\n");
242 irq_domain_remove(parent);
243 return -ENOMEM;
244 }
245
246 irq_domain_set_pm_device(msi_data->msi_domain, dev);
247
248 return 0;
249 }
250
251 /* Register offset of different version MU IP */
252 static const struct imx_mu_dcfg imx_mu_cfg_imx6sx = {
253 .type = 0,
254 .xTR = 0x0,
255 .xRR = 0x10,
256 .xSR = {
257 [IMX_MU_SR] = 0x20,
258 [IMX_MU_GSR] = 0x20,
259 [IMX_MU_TSR] = 0x20,
260 [IMX_MU_RSR] = 0x20,
261 },
262 .xCR = {
263 [IMX_MU_GIER] = 0x24,
264 [IMX_MU_GCR] = 0x24,
265 [IMX_MU_TCR] = 0x24,
266 [IMX_MU_RCR] = 0x24,
267 },
268 };
269
270 static const struct imx_mu_dcfg imx_mu_cfg_imx7ulp = {
271 .type = 0,
272 .xTR = 0x20,
273 .xRR = 0x40,
274 .xSR = {
275 [IMX_MU_SR] = 0x60,
276 [IMX_MU_GSR] = 0x60,
277 [IMX_MU_TSR] = 0x60,
278 [IMX_MU_RSR] = 0x60,
279 },
280 .xCR = {
281 [IMX_MU_GIER] = 0x64,
282 [IMX_MU_GCR] = 0x64,
283 [IMX_MU_TCR] = 0x64,
284 [IMX_MU_RCR] = 0x64,
285 },
286 };
287
288 static const struct imx_mu_dcfg imx_mu_cfg_imx8ulp = {
289 .type = IMX_MU_V2,
290 .xTR = 0x200,
291 .xRR = 0x280,
292 .xSR = {
293 [IMX_MU_SR] = 0xC,
294 [IMX_MU_GSR] = 0x118,
295 [IMX_MU_TSR] = 0x124,
296 [IMX_MU_RSR] = 0x12C,
297 },
298 .xCR = {
299 [IMX_MU_GIER] = 0x110,
300 [IMX_MU_GCR] = 0x114,
301 [IMX_MU_TCR] = 0x120,
302 [IMX_MU_RCR] = 0x128
303 },
304 };
305
imx_mu_of_init(struct device_node * dn,struct device_node * parent,const struct imx_mu_dcfg * cfg)306 static int __init imx_mu_of_init(struct device_node *dn,
307 struct device_node *parent,
308 const struct imx_mu_dcfg *cfg)
309 {
310 struct platform_device *pdev = of_find_device_by_node(dn);
311 struct device_link *pd_link_a;
312 struct device_link *pd_link_b;
313 struct imx_mu_msi *msi_data;
314 struct resource *res;
315 struct device *pd_a;
316 struct device *pd_b;
317 struct device *dev;
318 int ret;
319 int irq;
320
321 dev = &pdev->dev;
322
323 msi_data = devm_kzalloc(&pdev->dev, sizeof(*msi_data), GFP_KERNEL);
324 if (!msi_data)
325 return -ENOMEM;
326
327 msi_data->cfg = cfg;
328
329 msi_data->regs = devm_platform_ioremap_resource_byname(pdev, "processor-a-side");
330 if (IS_ERR(msi_data->regs)) {
331 dev_err(&pdev->dev, "failed to initialize 'regs'\n");
332 return PTR_ERR(msi_data->regs);
333 }
334
335 res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "processor-b-side");
336 if (!res)
337 return -EIO;
338
339 msi_data->msiir_addr = res->start + msi_data->cfg->xTR;
340
341 irq = platform_get_irq(pdev, 0);
342 if (irq <= 0)
343 return -ENODEV;
344
345 platform_set_drvdata(pdev, msi_data);
346
347 msi_data->clk = devm_clk_get(dev, NULL);
348 if (IS_ERR(msi_data->clk))
349 return PTR_ERR(msi_data->clk);
350
351 pd_a = dev_pm_domain_attach_by_name(dev, "processor-a-side");
352 if (IS_ERR(pd_a))
353 return PTR_ERR(pd_a);
354
355 pd_b = dev_pm_domain_attach_by_name(dev, "processor-b-side");
356 if (IS_ERR(pd_b))
357 return PTR_ERR(pd_b);
358
359 pd_link_a = device_link_add(dev, pd_a,
360 DL_FLAG_STATELESS |
361 DL_FLAG_PM_RUNTIME |
362 DL_FLAG_RPM_ACTIVE);
363
364 if (!pd_link_a) {
365 dev_err(dev, "Failed to add device_link to mu a.\n");
366 goto err_pd_a;
367 }
368
369 pd_link_b = device_link_add(dev, pd_b,
370 DL_FLAG_STATELESS |
371 DL_FLAG_PM_RUNTIME |
372 DL_FLAG_RPM_ACTIVE);
373
374
375 if (!pd_link_b) {
376 dev_err(dev, "Failed to add device_link to mu a.\n");
377 goto err_pd_b;
378 }
379
380 ret = imx_mu_msi_domains_init(msi_data, dev);
381 if (ret)
382 goto err_dm_init;
383
384 pm_runtime_enable(dev);
385
386 irq_set_chained_handler_and_data(irq,
387 imx_mu_msi_irq_handler,
388 msi_data);
389
390 return 0;
391
392 err_dm_init:
393 device_link_remove(dev, pd_b);
394 err_pd_b:
395 device_link_remove(dev, pd_a);
396 err_pd_a:
397 return -EINVAL;
398 }
399
imx_mu_runtime_suspend(struct device * dev)400 static int __maybe_unused imx_mu_runtime_suspend(struct device *dev)
401 {
402 struct imx_mu_msi *priv = dev_get_drvdata(dev);
403
404 clk_disable_unprepare(priv->clk);
405
406 return 0;
407 }
408
imx_mu_runtime_resume(struct device * dev)409 static int __maybe_unused imx_mu_runtime_resume(struct device *dev)
410 {
411 struct imx_mu_msi *priv = dev_get_drvdata(dev);
412 int ret;
413
414 ret = clk_prepare_enable(priv->clk);
415 if (ret)
416 dev_err(dev, "failed to enable clock\n");
417
418 return ret;
419 }
420
421 static const struct dev_pm_ops imx_mu_pm_ops = {
422 SET_RUNTIME_PM_OPS(imx_mu_runtime_suspend,
423 imx_mu_runtime_resume, NULL)
424 };
425
imx_mu_imx7ulp_of_init(struct device_node * dn,struct device_node * parent)426 static int __init imx_mu_imx7ulp_of_init(struct device_node *dn,
427 struct device_node *parent)
428 {
429 return imx_mu_of_init(dn, parent, &imx_mu_cfg_imx7ulp);
430 }
431
imx_mu_imx6sx_of_init(struct device_node * dn,struct device_node * parent)432 static int __init imx_mu_imx6sx_of_init(struct device_node *dn,
433 struct device_node *parent)
434 {
435 return imx_mu_of_init(dn, parent, &imx_mu_cfg_imx6sx);
436 }
437
imx_mu_imx8ulp_of_init(struct device_node * dn,struct device_node * parent)438 static int __init imx_mu_imx8ulp_of_init(struct device_node *dn,
439 struct device_node *parent)
440 {
441 return imx_mu_of_init(dn, parent, &imx_mu_cfg_imx8ulp);
442 }
443
444 IRQCHIP_PLATFORM_DRIVER_BEGIN(imx_mu_msi)
445 IRQCHIP_MATCH("fsl,imx7ulp-mu-msi", imx_mu_imx7ulp_of_init)
446 IRQCHIP_MATCH("fsl,imx6sx-mu-msi", imx_mu_imx6sx_of_init)
447 IRQCHIP_MATCH("fsl,imx8ulp-mu-msi", imx_mu_imx8ulp_of_init)
448 IRQCHIP_PLATFORM_DRIVER_END(imx_mu_msi, .pm = &imx_mu_pm_ops)
449
450
451 MODULE_AUTHOR("Frank Li <Frank.Li@nxp.com>");
452 MODULE_DESCRIPTION("Freescale MU MSI controller driver");
453 MODULE_LICENSE("GPL");
454