8  * Baikal-T1 APB-bus driver
38  * struct bt1_apb - Baikal-T1 APB EHB private data
40  * @regs: APB EHB registers map.
43  * @rate: APB-bus reference clock rate.
44  * @pclk: APB-reference clock.
45  * @prst: APB domain reset line.
71 static inline unsigned long bt1_apb_n_to_timeout_us(struct bt1_apb *apb, u32 n)  in bt1_apb_n_to_timeout_us()  argument
75 	do_div(timeout, apb->rate);  in bt1_apb_n_to_timeout_us()
81 static inline unsigned long bt1_apb_timeout_to_n_us(struct bt1_apb *apb,  in bt1_apb_timeout_to_n_us()  argument
84 	u64 n = (u64)timeout * apb->rate;  in bt1_apb_timeout_to_n_us()
94 	struct bt1_apb *apb = data;  in bt1_apb_isr()  local
97 	regmap_read(apb->regs, APB_EHB_ADDR, &addr);  in bt1_apb_isr()
99 	dev_crit_ratelimited(apb->dev,  in bt1_apb_isr()
100 		"APB-bus fault %d: Slave access timeout at 0x%08x\n",  in bt1_apb_isr()
101 		atomic_inc_return(&apb->count),  in bt1_apb_isr()
113 	regmap_update_bits(apb->regs, APB_EHB_ISR, APB_EHB_ISR_PENDING, 0);  in bt1_apb_isr()
120 	struct bt1_apb *apb = data;  in bt1_apb_clear_data()  local
121 	struct platform_device *pdev = to_platform_device(apb->dev);  in bt1_apb_clear_data()
129 	struct bt1_apb *apb;  in bt1_apb_create_data()  local
132 	apb = devm_kzalloc(dev, sizeof(*apb), GFP_KERNEL);  in bt1_apb_create_data()
133 	if (!apb)  in bt1_apb_create_data()
136 	ret = devm_add_action(dev, bt1_apb_clear_data, apb);  in bt1_apb_create_data()
138 		dev_err(dev, "Can't add APB EHB data clear action\n");  in bt1_apb_create_data()
142 	apb->dev = dev;  in bt1_apb_create_data()
143 	atomic_set(&apb->count, 0);  in bt1_apb_create_data()
144 	platform_set_drvdata(pdev, apb);  in bt1_apb_create_data()
146 	return apb;  in bt1_apb_create_data()
149 static int bt1_apb_request_regs(struct bt1_apb *apb)  in bt1_apb_request_regs()  argument
151 	struct platform_device *pdev = to_platform_device(apb->dev);  in bt1_apb_request_regs()
156 		dev_err(apb->dev, "Couldn't map APB EHB registers\n");  in bt1_apb_request_regs()
160 	apb->regs = devm_regmap_init_mmio(apb->dev, regs, &bt1_apb_regmap_cfg);  in bt1_apb_request_regs()
161 	if (IS_ERR(apb->regs)) {  in bt1_apb_request_regs()
162 		dev_err(apb->dev, "Couldn't create APB EHB regmap\n");  in bt1_apb_request_regs()
163 		return PTR_ERR(apb->regs);  in bt1_apb_request_regs()
166 	apb->res = devm_platform_ioremap_resource_byname(pdev, "nodev");  in bt1_apb_request_regs()
167 	if (IS_ERR(apb->res))  in bt1_apb_request_regs()
168 		dev_err(apb->dev, "Couldn't map reserved region\n");  in bt1_apb_request_regs()
170 	return PTR_ERR_OR_ZERO(apb->res);  in bt1_apb_request_regs()
173 static int bt1_apb_request_rst(struct bt1_apb *apb)  in bt1_apb_request_rst()  argument
177 	apb->prst = devm_reset_control_get_optional_exclusive(apb->dev, "prst");  in bt1_apb_request_rst()
178 	if (IS_ERR(apb->prst))  in bt1_apb_request_rst()
179 		return dev_err_probe(apb->dev, PTR_ERR(apb->prst),  in bt1_apb_request_rst()
182 	ret = reset_control_deassert(apb->prst);  in bt1_apb_request_rst()
184 		dev_err(apb->dev, "Failed to deassert the reset line\n");  in bt1_apb_request_rst()
191 	struct bt1_apb *apb = data;  in bt1_apb_disable_clk()  local
193 	clk_disable_unprepare(apb->pclk);  in bt1_apb_disable_clk()
196 static int bt1_apb_request_clk(struct bt1_apb *apb)  in bt1_apb_request_clk()  argument
200 	apb->pclk = devm_clk_get(apb->dev, "pclk");  in bt1_apb_request_clk()
201 	if (IS_ERR(apb->pclk))  in bt1_apb_request_clk()
202 		return dev_err_probe(apb->dev, PTR_ERR(apb->pclk),  in bt1_apb_request_clk()
203 				     "Couldn't get APB clock descriptor\n");  in bt1_apb_request_clk()
205 	ret = clk_prepare_enable(apb->pclk);  in bt1_apb_request_clk()
207 		dev_err(apb->dev, "Couldn't enable the APB clock\n");  in bt1_apb_request_clk()
211 	ret = devm_add_action_or_reset(apb->dev, bt1_apb_disable_clk, apb);  in bt1_apb_request_clk()
213 		dev_err(apb->dev, "Can't add APB EHB clocks disable action\n");  in bt1_apb_request_clk()
217 	apb->rate = clk_get_rate(apb->pclk);  in bt1_apb_request_clk()
218 	if (!apb->rate) {  in bt1_apb_request_clk()
219 		dev_err(apb->dev, "Invalid clock rate\n");  in bt1_apb_request_clk()
228 	struct bt1_apb *apb = data;  in bt1_apb_clear_irq()  local
230 	regmap_update_bits(apb->regs, APB_EHB_ISR, APB_EHB_ISR_MASK, 0);  in bt1_apb_clear_irq()
233 static int bt1_apb_request_irq(struct bt1_apb *apb)  in bt1_apb_request_irq()  argument
235 	struct platform_device *pdev = to_platform_device(apb->dev);  in bt1_apb_request_irq()
238 	apb->irq = platform_get_irq(pdev, 0);  in bt1_apb_request_irq()
239 	if (apb->irq < 0)  in bt1_apb_request_irq()
240 		return apb->irq;  in bt1_apb_request_irq()
242 	ret = devm_request_irq(apb->dev, apb->irq, bt1_apb_isr, IRQF_SHARED,  in bt1_apb_request_irq()
243 			       "bt1-apb", apb);  in bt1_apb_request_irq()
245 		dev_err(apb->dev, "Couldn't request APB EHB IRQ\n");  in bt1_apb_request_irq()
249 	ret = devm_add_action(apb->dev, bt1_apb_clear_irq, apb);  in bt1_apb_request_irq()
251 		dev_err(apb->dev, "Can't add APB EHB IRQs clear action\n");  in bt1_apb_request_irq()
256 	regmap_update_bits(apb->regs, APB_EHB_ISR,  in bt1_apb_request_irq()
266 	struct bt1_apb *apb = dev_get_drvdata(dev);  in count_show()  local
268 	return scnprintf(buf, PAGE_SIZE, "%d\n", atomic_read(&apb->count));  in count_show()
275 	struct bt1_apb *apb = dev_get_drvdata(dev);  in timeout_show()  local
280 	ret = regmap_read(apb->regs, APB_EHB_TIMEOUT, &n);  in timeout_show()
284 	timeout = bt1_apb_n_to_timeout_us(apb, n);  in timeout_show()
293 	struct bt1_apb *apb = dev_get_drvdata(dev);  in timeout_store()  local
301 	n = bt1_apb_timeout_to_n_us(apb, timeout);  in timeout_store()
304 	ret = regmap_write(apb->regs, APB_EHB_TIMEOUT, n);  in timeout_store()
320 	struct bt1_apb *apb = dev_get_drvdata(dev);  in inject_error_store()  local
323 	 * Either dummy read from the unmapped address in the APB IO area  in inject_error_store()
327 		readl(apb->res);  in inject_error_store()
329 		regmap_update_bits(apb->regs, APB_EHB_ISR, APB_EHB_ISR_PENDING,  in inject_error_store()
348 	struct bt1_apb *apb = data;  in bt1_apb_remove_sysfs()  local
350 	device_remove_groups(apb->dev, bt1_apb_sysfs_groups);  in bt1_apb_remove_sysfs()
353 static int bt1_apb_init_sysfs(struct bt1_apb *apb)  in bt1_apb_init_sysfs()  argument
357 	ret = device_add_groups(apb->dev, bt1_apb_sysfs_groups);  in bt1_apb_init_sysfs()
359 		dev_err(apb->dev, "Failed to create EHB APB sysfs nodes\n");  in bt1_apb_init_sysfs()
363 	ret = devm_add_action_or_reset(apb->dev, bt1_apb_remove_sysfs, apb);  in bt1_apb_init_sysfs()
365 		dev_err(apb->dev, "Can't add APB EHB sysfs remove action\n");  in bt1_apb_init_sysfs()
372 	struct bt1_apb *apb;  in bt1_apb_probe()  local
375 	apb = bt1_apb_create_data(pdev);  in bt1_apb_probe()
376 	if (IS_ERR(apb))  in bt1_apb_probe()
377 		return PTR_ERR(apb);  in bt1_apb_probe()
379 	ret = bt1_apb_request_regs(apb);  in bt1_apb_probe()
383 	ret = bt1_apb_request_rst(apb);  in bt1_apb_probe()
387 	ret = bt1_apb_request_clk(apb);  in bt1_apb_probe()
391 	ret = bt1_apb_request_irq(apb);  in bt1_apb_probe()
395 	ret = bt1_apb_init_sysfs(apb);  in bt1_apb_probe()
403 	{ .compatible = "baikal,bt1-apb" },
411 		.name = "bt1-apb",
418 MODULE_DESCRIPTION("Baikal-T1 APB-bus driver");