1 // SPDX-License-Identifier: GPL-2.0+
5  * Even though clk-bcm2835 provides an interface to the hardware registers for
8  * over-temperature and under-voltage protections provided by the firmware.
14 #include <linux/clk-provider.h>
19 #include <soc/bcm2835/raspberrypi-firmware.h>
35 	[RPI_FIRMWARE_PIXEL_BVB_CLK_ID]	= "pixel-bvb",
83 		 * always use the minimum the drivers will let us.
107 		 * driver instances, let's always use the minimum the
132  * clock (pllb) which we enable by default as turbo mode will alter multiple
141  * https://github.com/raspberrypi/firmware/wiki/Mailbox-property-interface
154 		.id = cpu_to_le32(data->id),  in raspberrypi_clock_property()
173 	struct raspberrypi_clk *rpi = data->rpi;  in raspberrypi_fw_is_prepared()
177 	ret = raspberrypi_clock_property(rpi->firmware, data,  in raspberrypi_fw_is_prepared()
191 	struct raspberrypi_clk *rpi = data->rpi;  in raspberrypi_fw_get_rate()
195 	ret = raspberrypi_clock_property(rpi->firmware, data,  in raspberrypi_fw_get_rate()
208 	struct raspberrypi_clk *rpi = data->rpi;  in raspberrypi_fw_set_rate()
212 	ret = raspberrypi_clock_property(rpi->firmware, data,  in raspberrypi_fw_set_rate()
215 		dev_err_ratelimited(rpi->dev, "Failed to change %s frequency: %d\n",  in raspberrypi_fw_set_rate()
226 	struct raspberrypi_clk_variant *variant = data->variant;  in raspberrypi_fw_dumb_determine_rate()
234 	req->rate = clamp(req->rate, req->min_rate, req->max_rate);  in raspberrypi_fw_dumb_determine_rate()
241 	if (variant->minimize && req->min_rate > 0)  in raspberrypi_fw_dumb_determine_rate()
242 		req->rate = req->min_rate;  in raspberrypi_fw_dumb_determine_rate()
264 	data = devm_kzalloc(rpi->dev, sizeof(*data), GFP_KERNEL);  in raspberrypi_clk_register()
266 		return ERR_PTR(-ENOMEM);  in raspberrypi_clk_register()
267 	data->rpi = rpi;  in raspberrypi_clk_register()
268 	data->id = id;  in raspberrypi_clk_register()
269 	data->variant = variant;  in raspberrypi_clk_register()
271 	init.name = devm_kasprintf(rpi->dev, GFP_KERNEL,  in raspberrypi_clk_register()
272 				   "fw-clk-%s",  in raspberrypi_clk_register()
277 	data->hw.init = &init;  in raspberrypi_clk_register()
279 	ret = raspberrypi_clock_property(rpi->firmware, data,  in raspberrypi_clk_register()
283 		dev_err(rpi->dev, "Failed to get clock %d min freq: %d\n",  in raspberrypi_clk_register()
288 	ret = raspberrypi_clock_property(rpi->firmware, data,  in raspberrypi_clk_register()
292 		dev_err(rpi->dev, "Failed to get clock %d max freq: %d\n",  in raspberrypi_clk_register()
297 	ret = devm_clk_hw_register(rpi->dev, &data->hw);  in raspberrypi_clk_register()
301 	clk_hw_set_rate_range(&data->hw, min_rate, max_rate);  in raspberrypi_clk_register()
303 	if (variant->clkdev) {  in raspberrypi_clk_register()
304 		ret = devm_clk_hw_register_clkdev(rpi->dev, &data->hw,  in raspberrypi_clk_register()
305 						  NULL, variant->clkdev);  in raspberrypi_clk_register()
307 			dev_err(rpi->dev, "Failed to initialize clkdev\n");  in raspberrypi_clk_register()
312 	if (variant->min_rate) {  in raspberrypi_clk_register()
315 		clk_hw_set_rate_range(&data->hw, variant->min_rate, max_rate);  in raspberrypi_clk_register()
317 		rate = raspberrypi_fw_get_rate(&data->hw, 0);  in raspberrypi_clk_register()
318 		if (rate < variant->min_rate) {  in raspberrypi_clk_register()
319 			ret = raspberrypi_fw_set_rate(&data->hw, variant->min_rate, 0);  in raspberrypi_clk_register()
325 	return &data->hw;  in raspberrypi_clk_register()
344 	clks = devm_kcalloc(rpi->dev,  in raspberrypi_discover_clocks()
348 		return -ENOMEM;  in raspberrypi_discover_clocks()
350 	ret = rpi_firmware_property(rpi->firmware, RPI_FIRMWARE_GET_CLOCKS,  in raspberrypi_discover_clocks()
356 	while (clks->id) {  in raspberrypi_discover_clocks()
359 		if (clks->id >= RPI_FIRMWARE_NUM_CLK_ID) {  in raspberrypi_discover_clocks()
360 			dev_err(rpi->dev, "Unknown clock id: %u (max: %u)\n",  in raspberrypi_discover_clocks()
361 					   clks->id, RPI_FIRMWARE_NUM_CLK_ID - 1);  in raspberrypi_discover_clocks()
362 			return -EINVAL;  in raspberrypi_discover_clocks()
365 		variant = &raspberrypi_clk_variants[clks->id];  in raspberrypi_discover_clocks()
366 		if (variant->export) {  in raspberrypi_discover_clocks()
369 			hw = raspberrypi_clk_register(rpi, clks->parent,  in raspberrypi_discover_clocks()
370 						      clks->id, variant);  in raspberrypi_discover_clocks()
374 			data->num = clks->id + 1;  in raspberrypi_discover_clocks()
375 			data->hws[clks->id] = hw;  in raspberrypi_discover_clocks()
388 	struct device *dev = &pdev->dev;  in raspberrypi_clk_probe()
394 	 * We can be probed either through the an old-fashioned  in raspberrypi_clk_probe()
398 	if (dev->of_node)  in raspberrypi_clk_probe()
399 		firmware_node = of_get_parent(dev->of_node);  in raspberrypi_clk_probe()
402 							"raspberrypi,bcm2835-firmware");  in raspberrypi_clk_probe()
405 		return -ENOENT;  in raspberrypi_clk_probe()
408 	firmware = devm_rpi_firmware_get(&pdev->dev, firmware_node);  in raspberrypi_clk_probe()
411 		return -EPROBE_DEFER;  in raspberrypi_clk_probe()
415 		return -ENOMEM;  in raspberrypi_clk_probe()
417 	rpi->dev = dev;  in raspberrypi_clk_probe()
418 	rpi->firmware = firmware;  in raspberrypi_clk_probe()
425 		return -ENOMEM;  in raspberrypi_clk_probe()
436 	rpi->cpufreq = platform_device_register_data(dev, "raspberrypi-cpufreq",  in raspberrypi_clk_probe()
437 						     -1, NULL, 0);  in raspberrypi_clk_probe()
446 	platform_device_unregister(rpi->cpufreq);  in raspberrypi_clk_remove()
450 	{ .compatible = "raspberrypi,firmware-clocks" },
457 		.name = "raspberrypi-clk",
468 MODULE_ALIAS("platform:raspberrypi-clk");