diff options
Diffstat (limited to 'drivers/firmware/raspberrypi.c')
| -rw-r--r-- | drivers/firmware/raspberrypi.c | 149 |
1 files changed, 147 insertions, 2 deletions
diff --git a/drivers/firmware/raspberrypi.c b/drivers/firmware/raspberrypi.c index 7ecde6921a0a..c8e8df969867 100644 --- a/drivers/firmware/raspberrypi.c +++ b/drivers/firmware/raspberrypi.c @@ -14,6 +14,7 @@ #include <linux/of.h> #include <linux/of_platform.h> #include <linux/platform_device.h> +#include <linux/reboot.h> #include <linux/slab.h> #include <soc/bcm2835/raspberrypi-firmware.h> @@ -32,8 +33,11 @@ struct rpi_firmware { u32 enabled; struct kref consumers; + u32 get_throttled; }; +static struct platform_device *g_pdev; + static DEFINE_MUTEX(transaction_lock); static void response_callback(struct mbox_client *cl, void *msg) @@ -176,15 +180,92 @@ int rpi_firmware_property(struct rpi_firmware *fw, kfree(data); + if ((tag == RPI_FIRMWARE_GET_THROTTLED) && + memcmp(&fw->get_throttled, tag_data, sizeof(fw->get_throttled))) { + memcpy(&fw->get_throttled, tag_data, sizeof(fw->get_throttled)); + sysfs_notify(&fw->cl.dev->kobj, NULL, "get_throttled"); + } + return ret; } EXPORT_SYMBOL_GPL(rpi_firmware_property); +static int rpi_firmware_notify_reboot(struct notifier_block *nb, + unsigned long action, + void *data) +{ + struct rpi_firmware *fw; + struct platform_device *pdev = g_pdev; + u32 reboot_flags = 0; + + if (!pdev) + return 0; + + fw = platform_get_drvdata(pdev); + if (!fw) + return 0; + + // The partition id is the first parameter followed by zero or + // more flags separated by spaces indicating the reason for the reboot. + // + // 'tryboot': Sets a one-shot flag which is cleared upon reboot and + // causes the tryboot.txt to be loaded instead of config.txt + // by the bootloader and the start.elf firmware. + // + // This is intended to allow automatic fallback to a known + // good image if an OS/FW upgrade fails. + // + // N.B. The firmware mechanism for storing reboot flags may vary + // on different Raspberry Pi models. + if (data && strstr(data, " tryboot")) + reboot_flags |= 0x1; + + // The mailbox might have been called earlier, directly via vcmailbox + // so only overwrite if reboot flags are passed to the reboot command. + if (reboot_flags) + (void)rpi_firmware_property(fw, RPI_FIRMWARE_SET_REBOOT_FLAGS, + &reboot_flags, sizeof(reboot_flags)); + + (void)rpi_firmware_property(fw, RPI_FIRMWARE_NOTIFY_REBOOT, NULL, 0); + + return 0; +} + +static ssize_t get_throttled_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct rpi_firmware *fw = dev_get_drvdata(dev); + + WARN_ONCE(1, "deprecated, use hwmon sysfs instead\n"); + + return sprintf(buf, "%x\n", fw->get_throttled); +} + +static DEVICE_ATTR_RO(get_throttled); + +static struct attribute *rpi_firmware_dev_attrs[] = { + &dev_attr_get_throttled.attr, + NULL, +}; + +static const struct attribute_group rpi_firmware_dev_group = { + .attrs = rpi_firmware_dev_attrs, +}; + static void rpi_firmware_print_firmware_revision(struct rpi_firmware *fw) { time64_t date_and_time; u32 packet; + static const char * const variant_strs[] = { + "unknown", + "start", + "start_x", + "start_db", + "start_cd", + }; + const char *variant_str = "cmd unsupported"; + u32 variant; int ret = rpi_firmware_property(fw, RPI_FIRMWARE_GET_FIRMWARE_REVISION, &packet, sizeof(packet)); @@ -194,7 +275,35 @@ rpi_firmware_print_firmware_revision(struct rpi_firmware *fw) /* This is not compatible with y2038 */ date_and_time = packet; - dev_info(fw->cl.dev, "Attached to firmware from %ptT\n", &date_and_time); + + ret = rpi_firmware_property(fw, RPI_FIRMWARE_GET_FIRMWARE_VARIANT, + &variant, sizeof(variant)); + + if (!ret) { + if (variant >= ARRAY_SIZE(variant_strs)) + variant = 0; + variant_str = variant_strs[variant]; + } + + dev_info(fw->cl.dev, + "Attached to firmware from %ptT, variant %s\n", + &date_and_time, variant_str); +} + +static void +rpi_firmware_print_firmware_hash(struct rpi_firmware *fw) +{ + u32 hash[5]; + int ret = rpi_firmware_property(fw, + RPI_FIRMWARE_GET_FIRMWARE_HASH, + hash, sizeof(hash)); + + if (ret) + return; + + dev_info(fw->cl.dev, + "Firmware hash is %08x%08x%08x%08x%08x\n", + hash[0], hash[1], hash[2], hash[3], hash[4]); } static void @@ -209,6 +318,11 @@ rpi_register_hwmon_driver(struct device *dev, struct rpi_firmware *fw) rpi_hwmon = platform_device_register_data(dev, "raspberrypi-hwmon", -1, NULL, 0); + + if (!IS_ERR_OR_NULL(rpi_hwmon)) { + if (devm_device_add_group(dev, &rpi_firmware_dev_group)) + dev_err(dev, "Failed to create get_trottled attr\n"); + } } static void rpi_register_clk_driver(struct device *dev) @@ -301,8 +415,10 @@ static int rpi_firmware_probe(struct platform_device *pdev) kref_init(&fw->consumers); platform_set_drvdata(pdev, fw); + g_pdev = pdev; rpi_firmware_print_firmware_revision(fw); + rpi_firmware_print_firmware_hash(fw); rpi_register_hwmon_driver(dev, fw); rpi_register_clk_driver(dev); @@ -329,6 +445,7 @@ static void rpi_firmware_remove(struct platform_device *pdev) rpi_clk = NULL; rpi_firmware_put(fw); + g_pdev = NULL; } static const struct of_device_id rpi_firmware_of_match[] = { @@ -408,7 +525,35 @@ static struct platform_driver rpi_firmware_driver = { .shutdown = rpi_firmware_shutdown, .remove = rpi_firmware_remove, }; -module_platform_driver(rpi_firmware_driver); + +static struct notifier_block rpi_firmware_reboot_notifier = { + .notifier_call = rpi_firmware_notify_reboot, +}; + +static int __init rpi_firmware_init(void) +{ + int ret = register_reboot_notifier(&rpi_firmware_reboot_notifier); + if (ret) + goto out1; + ret = platform_driver_register(&rpi_firmware_driver); + if (ret) + goto out2; + + return 0; + +out2: + unregister_reboot_notifier(&rpi_firmware_reboot_notifier); +out1: + return ret; +} +core_initcall(rpi_firmware_init); + +static void __init rpi_firmware_exit(void) +{ + platform_driver_unregister(&rpi_firmware_driver); + unregister_reboot_notifier(&rpi_firmware_reboot_notifier); +} +module_exit(rpi_firmware_exit); MODULE_AUTHOR("Eric Anholt <[email protected]>"); MODULE_DESCRIPTION("Raspberry Pi firmware driver"); |