diff options
Diffstat (limited to 'drivers/firmware/raspberrypi.c')
| -rw-r--r-- | drivers/firmware/raspberrypi.c | 196 |
1 files changed, 124 insertions, 72 deletions
diff --git a/drivers/firmware/raspberrypi.c b/drivers/firmware/raspberrypi.c index ef8098856a47..7ecde6921a0a 100644 --- a/drivers/firmware/raspberrypi.c +++ b/drivers/firmware/raspberrypi.c @@ -1,19 +1,20 @@ // SPDX-License-Identifier: GPL-2.0 /* - * Defines interfaces for interacting wtih the Raspberry Pi firmware's + * Defines interfaces for interacting with the Raspberry Pi firmware's * property channel. * * Copyright © 2015 Broadcom */ #include <linux/dma-mapping.h> +#include <linux/kref.h> #include <linux/mailbox_client.h> +#include <linux/mailbox_controller.h> #include <linux/module.h> +#include <linux/of.h> #include <linux/of_platform.h> #include <linux/platform_device.h> #include <linux/slab.h> -#include <linux/pci.h> -#include <linux/delay.h> #include <soc/bcm2835/raspberrypi-firmware.h> #define MBOX_MSG(chan, data28) (((data28) & ~0xf) | ((chan) & 0xf)) @@ -21,8 +22,6 @@ #define MBOX_DATA28(msg) ((msg) & ~0xf) #define MBOX_CHAN_PROPERTY 8 -#define VL805_PCI_CONFIG_VERSION_OFFSET 0x50 - static struct platform_device *rpi_hwmon; static struct platform_device *rpi_clk; @@ -31,6 +30,8 @@ struct rpi_firmware { struct mbox_chan *chan; /* The property channel. */ struct completion c; u32 enabled; + + struct kref consumers; }; static DEFINE_MUTEX(transaction_lock); @@ -61,7 +62,6 @@ rpi_firmware_transaction(struct rpi_firmware *fw, u32 chan, u32 data) ret = 0; } else { ret = -ETIMEDOUT; - WARN_ONCE(1, "Firmware transaction timeout"); } } else { dev_err(fw->cl.dev, "mbox_send_message returned %d\n", ret); @@ -97,8 +97,8 @@ int rpi_firmware_property_list(struct rpi_firmware *fw, if (size & 3) return -EINVAL; - buf = dma_alloc_coherent(fw->cl.dev, PAGE_ALIGN(size), &bus_addr, - GFP_ATOMIC); + buf = dma_alloc_coherent(fw->chan->mbox->dev, PAGE_ALIGN(size), + &bus_addr, GFP_ATOMIC); if (!buf) return -ENOMEM; @@ -124,9 +124,11 @@ int rpi_firmware_property_list(struct rpi_firmware *fw, dev_err(fw->cl.dev, "Request 0x%08x returned status 0x%08x\n", buf[2], buf[1]); ret = -EINVAL; + } else if (ret == -ETIMEDOUT) { + WARN_ONCE(1, "Firmware transaction 0x%08x timeout", buf[2]); } - dma_free_coherent(fw->cl.dev, PAGE_ALIGN(size), buf, bus_addr); + dma_free_coherent(fw->chan->mbox->dev, PAGE_ALIGN(size), buf, bus_addr); return ret; } @@ -181,6 +183,7 @@ EXPORT_SYMBOL_GPL(rpi_firmware_property); static void rpi_firmware_print_firmware_revision(struct rpi_firmware *fw) { + time64_t date_and_time; u32 packet; int ret = rpi_firmware_property(fw, RPI_FIRMWARE_GET_FIRMWARE_REVISION, @@ -189,7 +192,9 @@ rpi_firmware_print_firmware_revision(struct rpi_firmware *fw) if (ret) return; - dev_info(fw->cl.dev, "Attached to firmware from %ptT\n", &packet); + /* This is not compatible with y2038 */ + date_and_time = packet; + dev_info(fw->cl.dev, "Attached to firmware from %ptT\n", &date_and_time); } static void @@ -208,16 +213,76 @@ rpi_register_hwmon_driver(struct device *dev, struct rpi_firmware *fw) static void rpi_register_clk_driver(struct device *dev) { + struct device_node *firmware; + + /* + * Earlier DTs don't have a node for the firmware clocks but + * rely on us creating a platform device by hand. If we do + * have a node for the firmware clocks, just bail out here. + */ + firmware = of_get_compatible_child(dev->of_node, + "raspberrypi,firmware-clocks"); + if (firmware) { + of_node_put(firmware); + return; + } + rpi_clk = platform_device_register_data(dev, "raspberrypi-clk", -1, NULL, 0); } +unsigned int rpi_firmware_clk_get_max_rate(struct rpi_firmware *fw, unsigned int id) +{ + struct rpi_firmware_clk_rate_request msg = + RPI_FIRMWARE_CLK_RATE_REQUEST(id); + int ret; + + ret = rpi_firmware_property(fw, RPI_FIRMWARE_GET_MAX_CLOCK_RATE, + &msg, sizeof(msg)); + if (ret) + /* + * If our firmware doesn't support that operation, or fails, we + * assume the maximum clock rate is absolute maximum we can + * store over our type. + */ + return UINT_MAX; + + return le32_to_cpu(msg.rate); +} +EXPORT_SYMBOL_GPL(rpi_firmware_clk_get_max_rate); + +static void rpi_firmware_delete(struct kref *kref) +{ + struct rpi_firmware *fw = container_of(kref, struct rpi_firmware, + consumers); + + mbox_free_channel(fw->chan); + kfree(fw); +} + +void rpi_firmware_put(struct rpi_firmware *fw) +{ + kref_put(&fw->consumers, rpi_firmware_delete); +} +EXPORT_SYMBOL_GPL(rpi_firmware_put); + +static void devm_rpi_firmware_put(void *data) +{ + struct rpi_firmware *fw = data; + + rpi_firmware_put(fw); +} + static int rpi_firmware_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; struct rpi_firmware *fw; - fw = devm_kzalloc(dev, sizeof(*fw), GFP_KERNEL); + /* + * Memory will be freed by rpi_firmware_delete() once all users have + * released their firmware handles. Don't use devm_kzalloc() here. + */ + fw = kzalloc(sizeof(*fw), GFP_KERNEL); if (!fw) return -ENOMEM; @@ -228,12 +293,12 @@ static int rpi_firmware_probe(struct platform_device *pdev) fw->chan = mbox_request_channel(&fw->cl, 0); if (IS_ERR(fw->chan)) { int ret = PTR_ERR(fw->chan); - if (ret != -EPROBE_DEFER) - dev_err(dev, "Failed to get mbox channel: %d\n", ret); - return ret; + kfree(fw); + return dev_err_probe(dev, ret, "Failed to get mbox channel\n"); } init_completion(&fw->c); + kref_init(&fw->consumers); platform_set_drvdata(pdev, fw); @@ -254,7 +319,7 @@ static void rpi_firmware_shutdown(struct platform_device *pdev) rpi_firmware_property(fw, RPI_FIRMWARE_NOTIFY_REBOOT, NULL, 0); } -static int rpi_firmware_remove(struct platform_device *pdev) +static void rpi_firmware_remove(struct platform_device *pdev) { struct rpi_firmware *fw = platform_get_drvdata(pdev); @@ -262,90 +327,77 @@ static int rpi_firmware_remove(struct platform_device *pdev) rpi_hwmon = NULL; platform_device_unregister(rpi_clk); rpi_clk = NULL; - mbox_free_channel(fw->chan); - return 0; + rpi_firmware_put(fw); +} + +static const struct of_device_id rpi_firmware_of_match[] = { + { .compatible = "raspberrypi,bcm2835-firmware", }, + {}, +}; +MODULE_DEVICE_TABLE(of, rpi_firmware_of_match); + +struct device_node *rpi_firmware_find_node(void) +{ + return of_find_matching_node(NULL, rpi_firmware_of_match); } +EXPORT_SYMBOL_GPL(rpi_firmware_find_node); /** * rpi_firmware_get - Get pointer to rpi_firmware structure. * @firmware_node: Pointer to the firmware Device Tree node. * + * The reference to rpi_firmware has to be released with rpi_firmware_put(). + * * Returns NULL is the firmware device is not ready. */ struct rpi_firmware *rpi_firmware_get(struct device_node *firmware_node) { struct platform_device *pdev = of_find_device_by_node(firmware_node); + struct rpi_firmware *fw; if (!pdev) return NULL; - return platform_get_drvdata(pdev); + fw = platform_get_drvdata(pdev); + if (!fw) + goto err_put_device; + + if (!kref_get_unless_zero(&fw->consumers)) + goto err_put_device; + + put_device(&pdev->dev); + + return fw; + +err_put_device: + put_device(&pdev->dev); + return NULL; } EXPORT_SYMBOL_GPL(rpi_firmware_get); -/* - * The Raspberry Pi 4 gets its USB functionality from VL805, a PCIe chip that - * implements xHCI. After a PCI reset, VL805's firmware may either be loaded - * directly from an EEPROM or, if not present, by the SoC's co-processor, - * VideoCore. RPi4's VideoCore OS contains both the non public firmware load - * logic and the VL805 firmware blob. This function triggers the aforementioned - * process. +/** + * devm_rpi_firmware_get - Get pointer to rpi_firmware structure. + * @dev: The firmware device structure + * @firmware_node: Pointer to the firmware Device Tree node. + * + * Returns NULL is the firmware device is not ready. */ -int rpi_firmware_init_vl805(struct pci_dev *pdev) +struct rpi_firmware *devm_rpi_firmware_get(struct device *dev, + struct device_node *firmware_node) { - struct device_node *fw_np; struct rpi_firmware *fw; - u32 dev_addr, version; - int ret; - - fw_np = of_find_compatible_node(NULL, NULL, - "raspberrypi,bcm2835-firmware"); - if (!fw_np) - return 0; - fw = rpi_firmware_get(fw_np); - of_node_put(fw_np); + fw = rpi_firmware_get(firmware_node); if (!fw) - return -ENODEV; - - /* - * Make sure we don't trigger a firmware load unnecessarily. - * - * If something went wrong with PCI, this whole exercise would be - * futile as VideoCore expects from us a configured PCI bus. Just take - * the faulty version (likely ~0) and let xHCI's registration fail - * further down the line. - */ - pci_read_config_dword(pdev, VL805_PCI_CONFIG_VERSION_OFFSET, &version); - if (version) - goto exit; - - dev_addr = pdev->bus->number << 20 | PCI_SLOT(pdev->devfn) << 15 | - PCI_FUNC(pdev->devfn) << 12; - - ret = rpi_firmware_property(fw, RPI_FIRMWARE_NOTIFY_XHCI_RESET, - &dev_addr, sizeof(dev_addr)); - if (ret) - return ret; - - /* Wait for vl805 to startup */ - usleep_range(200, 1000); + return NULL; - pci_read_config_dword(pdev, VL805_PCI_CONFIG_VERSION_OFFSET, - &version); -exit: - pci_info(pdev, "VL805 firmware version %08x\n", version); + if (devm_add_action_or_reset(dev, devm_rpi_firmware_put, fw)) + return NULL; - return 0; + return fw; } -EXPORT_SYMBOL_GPL(rpi_firmware_init_vl805); - -static const struct of_device_id rpi_firmware_of_match[] = { - { .compatible = "raspberrypi,bcm2835-firmware", }, - {}, -}; -MODULE_DEVICE_TABLE(of, rpi_firmware_of_match); +EXPORT_SYMBOL_GPL(devm_rpi_firmware_get); static struct platform_driver rpi_firmware_driver = { .driver = { |