2  * Atmel AT91 SAM9 & SAMA5 SoCs reset code
20 #include <linux/reset-controller.h>
25 #include <dt-bindings/reset/sama7g5-reset.h>
27 #define AT91_RSTC_CR	0x00		/* Reset Controller Control Register */
28 #define AT91_RSTC_PROCRST	BIT(0)		/* Processor Reset */
29 #define AT91_RSTC_PERRST	BIT(2)		/* Peripheral Reset */
30 #define AT91_RSTC_EXTRST	BIT(3)		/* External Reset */
33 #define AT91_RSTC_SR	0x04		/* Reset Controller Status Register */
34 #define AT91_RSTC_URSTS		BIT(0)		/* User Reset Status */
35 #define AT91_RSTC_RSTTYP	GENMASK(10, 8)	/* Reset Type */
37 #define AT91_RSTC_SRCMP		BIT(17)		/* Software Reset Command in Progress */
39 #define AT91_RSTC_MR	0x08		/* Reset Controller Mode Register */
40 #define AT91_RSTC_URSTEN	BIT(0)		/* User Reset Enable */
41 #define AT91_RSTC_URSTASYNC	BIT(2)		/* User Reset Asynchronous Control */
42 #define AT91_RSTC_URSTIEN	BIT(4)		/* User Reset Interrupt Enable */
43 #define AT91_RSTC_ERSTL		GENMASK(11, 8)	/* External Reset Length */
46  * enum reset_type - reset types
47  * @RESET_TYPE_GENERAL:		first power-up reset
50  * @RESET_TYPE_SOFTWARE:	processor reset required by software
54  * @RESET_TYPE_ULP2:		ULP2 reset
68  * struct at91_reset - AT91 reset specific data structure
69  * @rstc_base:		base address for system reset
71  * @dev_base:		base address for devices reset
73  * @data:		platform specific reset data
74  * @rcdev:		reset controller device
75  * @lock:		lock for devices reset register access
76  * @nb:			reset notifier block
77  * @args:		SoC specific system reset arguments
96  * struct at91_reset_data - AT91 reset data
97  * @reset_args:			SoC specific system reset arguments
99  * @device_reset_min_id:	min id for device reset
100  * @device_reset_max_id:	max id for device reset
111 * reset register it can be left driving the data bus and
117 	struct at91_reset *reset = container_of(this, struct at91_reset, nb);  in at91_reset()  local
135 		/* Reset CPU */  in at91_reset()
140 		: "r" (reset->ramc_base[0]),  in at91_reset()
141 		  "r" (reset->ramc_base[1]),  in at91_reset()
142 		  "r" (reset->rstc_base),  in at91_reset()
145 		  "r" (reset->data->reset_args),  in at91_reset()
146 		  "r" (reset->ramc_lpr)  in at91_reset()
160 		reason = "general reset";  in at91_reset_status()
166 		reason = "watchdog reset";  in at91_reset_status()
169 		reason = "software reset";  in at91_reset_status()
172 		reason = "user reset";  in at91_reset_status()
181 		reason = "ULP2 reset";  in at91_reset_status()
184 		reason = "unknown reset";  in at91_reset_status()
250 	struct at91_reset *reset = to_at91_reset(rcdev);  in at91_reset_update()  local
254 	spin_lock_irqsave(&reset->lock, flags);  in at91_reset_update()
255 	val = readl_relaxed(reset->dev_base);  in at91_reset_update()
260 	writel_relaxed(val, reset->dev_base);  in at91_reset_update()
261 	spin_unlock_irqrestore(&reset->lock, flags);  in at91_reset_update()
281 	struct at91_reset *reset = to_at91_reset(rcdev);  in at91_reset_dev_status()  local
284 	val = readl_relaxed(reset->dev_base);  in at91_reset_dev_status()
298 	struct at91_reset *reset = to_at91_reset(rcdev);  in at91_reset_of_xlate()  local
300 	if (!reset->data->n_device_reset ||  in at91_reset_of_xlate()
301 	    (reset_spec->args[0] < reset->data->device_reset_min_id ||  in at91_reset_of_xlate()
302 	     reset_spec->args[0] > reset->data->device_reset_max_id))  in at91_reset_of_xlate()
308 static int at91_rcdev_init(struct at91_reset *reset,  in at91_rcdev_init()  argument
311 	if (!reset->data->n_device_reset)  in at91_rcdev_init()
314 	reset->dev_base = devm_of_iomap(&pdev->dev, pdev->dev.of_node, 1,  in at91_rcdev_init()
316 	if (IS_ERR(reset->dev_base))  in at91_rcdev_init()
319 	spin_lock_init(&reset->lock);  in at91_rcdev_init()
320 	reset->rcdev.ops = &at91_reset_ops;  in at91_rcdev_init()
321 	reset->rcdev.owner = THIS_MODULE;  in at91_rcdev_init()
322 	reset->rcdev.of_node = pdev->dev.of_node;  in at91_rcdev_init()
323 	reset->rcdev.nr_resets = reset->data->n_device_reset;  in at91_rcdev_init()
324 	reset->rcdev.of_reset_n_cells = 1;  in at91_rcdev_init()
325 	reset->rcdev.of_xlate = at91_reset_of_xlate;  in at91_rcdev_init()
327 	return devm_reset_controller_register(&pdev->dev, &reset->rcdev);  in at91_rcdev_init()
333 	struct at91_reset *reset;  in at91_reset_probe()  local
337 	reset = devm_kzalloc(&pdev->dev, sizeof(*reset), GFP_KERNEL);  in at91_reset_probe()
338 	if (!reset)  in at91_reset_probe()
341 	reset->rstc_base = devm_of_iomap(&pdev->dev, pdev->dev.of_node, 0, NULL);  in at91_reset_probe()
342 	if (IS_ERR(reset->rstc_base)) {  in at91_reset_probe()
343 		dev_err(&pdev->dev, "Could not map reset controller address\n");  in at91_reset_probe()
350 			reset->ramc_lpr = (u32)match->data;  in at91_reset_probe()
351 			reset->ramc_base[idx] = devm_of_iomap(&pdev->dev, np, 0, NULL);  in at91_reset_probe()
352 			if (IS_ERR(reset->ramc_base[idx])) {  in at91_reset_probe()
361 	reset->data = device_get_match_data(&pdev->dev);  in at91_reset_probe()
362 	if (!reset->data)  in at91_reset_probe()
365 	reset->nb.notifier_call = at91_reset;  in at91_reset_probe()
366 	reset->nb.priority = 192;  in at91_reset_probe()
368 	reset->sclk = devm_clk_get(&pdev->dev, NULL);  in at91_reset_probe()
369 	if (IS_ERR(reset->sclk))  in at91_reset_probe()
370 		return PTR_ERR(reset->sclk);  in at91_reset_probe()
372 	ret = clk_prepare_enable(reset->sclk);  in at91_reset_probe()
378 	platform_set_drvdata(pdev, reset);  in at91_reset_probe()
380 	ret = at91_rcdev_init(reset, pdev);  in at91_reset_probe()
385 		u32 val = readl(reset->rstc_base + AT91_RSTC_MR);  in at91_reset_probe()
388 		       reset->rstc_base + AT91_RSTC_MR);  in at91_reset_probe()
391 	ret = register_restart_handler(&reset->nb);  in at91_reset_probe()
395 	at91_reset_status(pdev, reset->rstc_base);  in at91_reset_probe()
400 	clk_disable_unprepare(reset->sclk);  in at91_reset_probe()
406 	struct at91_reset *reset = platform_get_drvdata(pdev);  in at91_reset_remove()  local
408 	unregister_restart_handler(&reset->nb);  in at91_reset_remove()
409 	clk_disable_unprepare(reset->sclk);  in at91_reset_remove()
417 		.name = "at91-reset",
424 MODULE_DESCRIPTION("Reset driver for Atmel SoCs");