This gives us a function for making mailbox property channel requests of the firmware, which is most notable in that it will let us get and set clock rates. v2: Drop power-domains stuff for now since we don't have the driver core support to make it useful. Move to drivers/firmware/. Capitalize the enums. De-global the firmware variable. Use the firmware device to allocate our DMA buffer, so that the dma-ranges DT property gets respected. Simplify the property tag transaction interface even more, leaving a multi-tag interface still available. For conciseness, rename "raspberrypi" to "rpi" on all functions/enums/structs, and the "firmware" variable to "fw". Print when the driver is probed successfully, since debugging -EPROBE_DEFER handling is such a big part of bcm2835 development. Drop -EBUSY mailbox handling since the mailbox core has been fixed to return -EPROBE_DEFER in -next. v3: Use kernel-doc style for big comments (from Noralf), drop stale comment, use "dev" when freeing DMA as well. v4: Move description comment into copyright comment, drop a dead initialization of "ret", and print the firmware revision at probe time. v5: Rename the compatible to "raspberrypi,bcm2835-firmware", move include to not say "property", add functions to get struct rpi_firmware from the device_node and put when done, make property functions take the rpi_firmware instead and never return -EPROBE_DEFER, put the driver under its own RASPBERRYPI_FIRMWARE Kconfig. Signed-off-by: Eric Anholt <eric@xxxxxxxxxx> --- drivers/firmware/Kconfig | 7 + drivers/firmware/Makefile | 1 + drivers/firmware/raspberrypi.c | 272 +++++++++++++++++++++++++++++ include/soc/bcm2835/raspberrypi-firmware.h | 116 ++++++++++++ 4 files changed, 396 insertions(+) create mode 100644 drivers/firmware/raspberrypi.c create mode 100644 include/soc/bcm2835/raspberrypi-firmware.h diff --git a/drivers/firmware/Kconfig b/drivers/firmware/Kconfig index 6517132..564aa5b 100644 --- a/drivers/firmware/Kconfig +++ b/drivers/firmware/Kconfig @@ -136,6 +136,13 @@ config QCOM_SCM bool depends on ARM || ARM64 +config RASPBERRYPI_FIRMWARE + tristate "Raspberry Pi Firmware Driver" + depends on BCM2835_MBOX + help + This option enables support for communicating with the firmware on the + Raspberry Pi. + source "drivers/firmware/google/Kconfig" source "drivers/firmware/efi/Kconfig" diff --git a/drivers/firmware/Makefile b/drivers/firmware/Makefile index 3fdd391..ee101a2 100644 --- a/drivers/firmware/Makefile +++ b/drivers/firmware/Makefile @@ -13,6 +13,7 @@ obj-$(CONFIG_ISCSI_IBFT) += iscsi_ibft.o obj-$(CONFIG_FIRMWARE_MEMMAP) += memmap.o obj-$(CONFIG_QCOM_SCM) += qcom_scm.o CFLAGS_qcom_scm.o :=$(call as-instr,.arch_extension sec,-DREQUIRES_SEC=1) +obj-$(CONFIG_RASPBERRYPI_FIRMWARE) += raspberrypi.o obj-$(CONFIG_GOOGLE_FIRMWARE) += google/ obj-$(CONFIG_EFI) += efi/ diff --git a/drivers/firmware/raspberrypi.c b/drivers/firmware/raspberrypi.c new file mode 100644 index 0000000..e4a033a --- /dev/null +++ b/drivers/firmware/raspberrypi.c @@ -0,0 +1,272 @@ +/* + * Defines interfaces for interacting wtih the Raspberry Pi firmware's + * property channel. + * + * Copyright © 2015 Broadcom + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/dma-mapping.h> +#include <linux/mailbox_client.h> +#include <linux/module.h> +#include <linux/of_platform.h> +#include <linux/platform_device.h> +#include <soc/bcm2835/raspberrypi-firmware.h> + +#define MBOX_MSG(chan, data28) (((data28) & ~0xf) | ((chan) & 0xf)) +#define MBOX_CHAN(msg) ((msg) & 0xf) +#define MBOX_DATA28(msg) ((msg) & ~0xf) +#define MBOX_CHAN_PROPERTY 8 + +struct rpi_firmware { + struct mbox_client cl; + struct mbox_chan *chan; /* The property channel. */ + struct completion c; + u32 enabled; +}; + +static DEFINE_MUTEX(transaction_lock); + +static void response_callback(struct mbox_client *cl, void *msg) +{ + struct rpi_firmware *fw = container_of(cl, struct rpi_firmware, cl); + complete(&fw->c); +} + +/* + * Sends a request to the firmware through the BCM2835 mailbox driver, + * and synchronously waits for the reply. + */ +static int +rpi_firmware_transaction(struct rpi_firmware *fw, u32 chan, u32 data) +{ + u32 message = MBOX_MSG(chan, data); + int ret; + + WARN_ON(data & 0xf); + + mutex_lock(&transaction_lock); + reinit_completion(&fw->c); + ret = mbox_send_message(fw->chan, &message); + if (ret >= 0) { + wait_for_completion(&fw->c); + ret = 0; + } else { + dev_err(fw->cl.dev, "mbox_send_message returned %d\n", ret); + } + mutex_unlock(&transaction_lock); + + return ret; +} + +/** + * rpi_firmware_property_list - Submit firmware property list + * @of_node: Pointer to the firmware Device Tree node. + * @data: Buffer holding tags. + * @tag_size: Size of tags buffer. + * + * Submits a set of concatenated tags to the VPU firmware through the + * mailbox property interface. + * + * The buffer header and the ending tag are added by this function and + * don't need to be supplied, just the actual tags for your operation. + * See struct rpi_firmware_property_tag_header for the per-tag + * structure. + */ +int rpi_firmware_property_list(struct rpi_firmware *fw, + void *data, size_t tag_size) +{ + size_t size = tag_size + 12; + u32 *buf; + dma_addr_t bus_addr; + int ret; + + /* Packets are processed a dword at a time. */ + if (size & 3) + return -EINVAL; + + buf = dma_alloc_coherent(fw->cl.dev, PAGE_ALIGN(size), &bus_addr, + GFP_ATOMIC); + if (!buf) + return -ENOMEM; + + /* The firmware will error out without parsing in this case. */ + WARN_ON(size >= 1024 * 1024); + + buf[0] = size; + buf[1] = RPI_FIRMWARE_STATUS_REQUEST; + memcpy(&buf[2], data, tag_size); + buf[size / 4 - 1] = RPI_FIRMWARE_PROPERTY_END; + wmb(); + + ret = rpi_firmware_transaction(fw, MBOX_CHAN_PROPERTY, bus_addr); + + rmb(); + memcpy(data, &buf[2], tag_size); + if (ret == 0 && buf[1] != RPI_FIRMWARE_STATUS_SUCCESS) { + /* + * The tag name here might not be the one causing the + * error, if there were multiple tags in the request. + * But single-tag is the most common, so go with it. + */ + dev_err(fw->cl.dev, "Request 0x%08x returned status 0x%08x\n", + buf[2], buf[1]); + ret = -EINVAL; + } + + dma_free_coherent(fw->cl.dev, PAGE_ALIGN(size), buf, bus_addr); + + return ret; +} +EXPORT_SYMBOL_GPL(rpi_firmware_property_list); + +/** + * rpi_firmware_property - Submit single firmware property + * @of_node: Pointer to the firmware Device Tree node. + * @tag: One of enum_mbox_property_tag. + * @tag_data: Tag data buffer. + * @buf_size: Buffer size. + * + * Submits a single tag to the VPU firmware through the mailbox + * property interface. + * + * This is a convenience wrapper around + * rpi_firmware_property_list() to avoid some of the + * boilerplate in property calls. + */ +int rpi_firmware_property(struct rpi_firmware *fw, + u32 tag, void *tag_data, size_t buf_size) +{ + /* Single tags are very small (generally 8 bytes), so the + * stack should be safe. + */ + u8 data[buf_size + sizeof(struct rpi_firmware_property_tag_header)]; + struct rpi_firmware_property_tag_header *header = + (struct rpi_firmware_property_tag_header *)data; + int ret; + + header->tag = tag; + header->buf_size = buf_size; + header->req_resp_size = 0; + memcpy(data + sizeof(struct rpi_firmware_property_tag_header), + tag_data, buf_size); + + ret = rpi_firmware_property_list(fw, &data, sizeof(data)); + memcpy(tag_data, + data + sizeof(struct rpi_firmware_property_tag_header), + buf_size); + + return ret; +} +EXPORT_SYMBOL_GPL(rpi_firmware_property); + +static void +rpi_firmware_print_firmware_revision(struct rpi_firmware *fw) +{ + u32 packet; + int ret = rpi_firmware_property(fw, + RPI_FIRMWARE_GET_FIRMWARE_REVISION, + &packet, sizeof(packet)); + + if (ret == 0) { + struct tm tm; + + time_to_tm(packet, 0, &tm); + + dev_info(fw->cl.dev, + "Attached to firmware from %04ld-%02d-%02d %02d:%02d\n", + tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday, + tm.tm_hour, tm.tm_min); + } +} + +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); + if (!fw) + return -ENOMEM; + + fw->cl.dev = dev; + fw->cl.rx_callback = response_callback; + fw->cl.tx_block = true; + + 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; + } + + init_completion(&fw->c); + + platform_set_drvdata(pdev, fw); + + rpi_firmware_print_firmware_revision(fw); + + return 0; +} + +static int rpi_firmware_remove(struct platform_device *pdev) +{ + struct rpi_firmware *fw = platform_get_drvdata(pdev); + + mbox_free_channel(fw->chan); + + return 0; +} + +/* + * Returns the struct rpi_firmware if the firmware device is probed + * and available, otherwise NULL. + */ +struct rpi_firmware *rpi_firmware_get(struct device_node *firmware_node) +{ + struct platform_device *pdev = of_find_device_by_node(firmware_node); + + if (!pdev) + return NULL; + + if (!pdev->dev.driver) + return NULL; + + if (!try_module_get(pdev->dev.driver->owner)) + return NULL; + + return platform_get_drvdata(pdev); +} +EXPORT_SYMBOL_GPL(rpi_firmware_get); + +void rpi_firmware_put(struct rpi_firmware *fw) +{ + struct device *dev = fw->cl.dev; + + module_put(dev->driver->owner); +} +EXPORT_SYMBOL_GPL(rpi_firmware_put); + +static const struct of_device_id rpi_firmware_of_match[] = { + { .compatible = "raspberrypi,bcm2835-firmware", }, + {}, +}; +MODULE_DEVICE_TABLE(of, rpi_firmware_of_match); + +static struct platform_driver rpi_firmware_driver = { + .driver = { + .name = "raspberrypi-firmware", + .of_match_table = rpi_firmware_of_match, + }, + .probe = rpi_firmware_probe, + .remove = rpi_firmware_remove, +}; +module_platform_driver(rpi_firmware_driver); + +MODULE_AUTHOR("Eric Anholt <eric@xxxxxxxxxx>"); +MODULE_DESCRIPTION("Raspberry Pi firmware driver"); +MODULE_LICENSE("GPL v2"); diff --git a/include/soc/bcm2835/raspberrypi-firmware.h b/include/soc/bcm2835/raspberrypi-firmware.h new file mode 100644 index 0000000..55baf24 --- /dev/null +++ b/include/soc/bcm2835/raspberrypi-firmware.h @@ -0,0 +1,116 @@ +/* + * Copyright © 2015 Broadcom + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/types.h> +#include <linux/of_device.h> + +struct rpi_firmware; + +enum rpi_firmware_property_status { + RPI_FIRMWARE_STATUS_REQUEST = 0, + RPI_FIRMWARE_STATUS_SUCCESS = 0x80000000, + RPI_FIRMWARE_STATUS_ERROR = 0x80000001, +}; + +/** + * struct rpi_firmware_property_tag_header - Firmware property tag header + * @tag: One of enum_mbox_property_tag. + * @buf_size: The number of bytes in the value buffer following this + * struct. + * @req_resp_size: On submit, the length of the request (though it doesn't + * appear to be currently used by the firmware). On return, + * the length of the response (always 4 byte aligned), with + * the low bit set. + */ +struct rpi_firmware_property_tag_header { + u32 tag; + u32 buf_size; + u32 req_resp_size; +}; + +enum rpi_firmware_property_tag { + RPI_FIRMWARE_PROPERTY_END = 0, + RPI_FIRMWARE_GET_FIRMWARE_REVISION = 0x00000001, + + RPI_FIRMWARE_SET_CURSOR_INFO = 0x00008010, + RPI_FIRMWARE_SET_CURSOR_STATE = 0x00008011, + + RPI_FIRMWARE_GET_BOARD_MODEL = 0x00010001, + RPI_FIRMWARE_GET_BOARD_REVISION = 0x00010002, + RPI_FIRMWARE_GET_BOARD_MAC_ADDRESS = 0x00010003, + RPI_FIRMWARE_GET_BOARD_SERIAL = 0x00010004, + RPI_FIRMWARE_GET_ARM_MEMORY = 0x00010005, + RPI_FIRMWARE_GET_VC_MEMORY = 0x00010006, + RPI_FIRMWARE_GET_CLOCKS = 0x00010007, + RPI_FIRMWARE_GET_POWER_STATE = 0x00020001, + RPI_FIRMWARE_GET_TIMING = 0x00020002, + RPI_FIRMWARE_SET_POWER_STATE = 0x00028001, + RPI_FIRMWARE_GET_CLOCK_STATE = 0x00030001, + RPI_FIRMWARE_GET_CLOCK_RATE = 0x00030002, + RPI_FIRMWARE_GET_VOLTAGE = 0x00030003, + RPI_FIRMWARE_GET_MAX_CLOCK_RATE = 0x00030004, + RPI_FIRMWARE_GET_MAX_VOLTAGE = 0x00030005, + RPI_FIRMWARE_GET_TEMPERATURE = 0x00030006, + RPI_FIRMWARE_GET_MIN_CLOCK_RATE = 0x00030007, + RPI_FIRMWARE_GET_MIN_VOLTAGE = 0x00030008, + RPI_FIRMWARE_GET_TURBO = 0x00030009, + RPI_FIRMWARE_GET_MAX_TEMPERATURE = 0x0003000a, + RPI_FIRMWARE_ALLOCATE_MEMORY = 0x0003000c, + RPI_FIRMWARE_LOCK_MEMORY = 0x0003000d, + RPI_FIRMWARE_UNLOCK_MEMORY = 0x0003000e, + RPI_FIRMWARE_RELEASE_MEMORY = 0x0003000f, + RPI_FIRMWARE_EXECUTE_CODE = 0x00030010, + RPI_FIRMWARE_EXECUTE_QPU = 0x00030011, + RPI_FIRMWARE_SET_ENABLE_QPU = 0x00030012, + RPI_FIRMWARE_GET_DISPMANX_RESOURCE_MEM_HANDLE = 0x00030014, + RPI_FIRMWARE_GET_EDID_BLOCK = 0x00030020, + RPI_FIRMWARE_SET_CLOCK_STATE = 0x00038001, + RPI_FIRMWARE_SET_CLOCK_RATE = 0x00038002, + RPI_FIRMWARE_SET_VOLTAGE = 0x00038003, + RPI_FIRMWARE_SET_TURBO = 0x00038009, + + /* Dispmanx TAGS */ + RPI_FIRMWARE_FRAMEBUFFER_ALLOCATE = 0x00040001, + RPI_FIRMWARE_FRAMEBUFFER_BLANK = 0x00040002, + RPI_FIRMWARE_FRAMEBUFFER_GET_PHYSICAL_WIDTH_HEIGHT = 0x00040003, + RPI_FIRMWARE_FRAMEBUFFER_GET_VIRTUAL_WIDTH_HEIGHT = 0x00040004, + RPI_FIRMWARE_FRAMEBUFFER_GET_DEPTH = 0x00040005, + RPI_FIRMWARE_FRAMEBUFFER_GET_PIXEL_ORDER = 0x00040006, + RPI_FIRMWARE_FRAMEBUFFER_GET_ALPHA_MODE = 0x00040007, + RPI_FIRMWARE_FRAMEBUFFER_GET_PITCH = 0x00040008, + RPI_FIRMWARE_FRAMEBUFFER_GET_VIRTUAL_OFFSET = 0x00040009, + RPI_FIRMWARE_FRAMEBUFFER_GET_OVERSCAN = 0x0004000a, + RPI_FIRMWARE_FRAMEBUFFER_GET_PALETTE = 0x0004000b, + RPI_FIRMWARE_FRAMEBUFFER_RELEASE = 0x00048001, + RPI_FIRMWARE_FRAMEBUFFER_TEST_PHYSICAL_WIDTH_HEIGHT = 0x00044003, + RPI_FIRMWARE_FRAMEBUFFER_TEST_VIRTUAL_WIDTH_HEIGHT = 0x00044004, + RPI_FIRMWARE_FRAMEBUFFER_TEST_DEPTH = 0x00044005, + RPI_FIRMWARE_FRAMEBUFFER_TEST_PIXEL_ORDER = 0x00044006, + RPI_FIRMWARE_FRAMEBUFFER_TEST_ALPHA_MODE = 0x00044007, + RPI_FIRMWARE_FRAMEBUFFER_TEST_VIRTUAL_OFFSET = 0x00044009, + RPI_FIRMWARE_FRAMEBUFFER_TEST_OVERSCAN = 0x0004400a, + RPI_FIRMWARE_FRAMEBUFFER_TEST_PALETTE = 0x0004400b, + RPI_FIRMWARE_FRAMEBUFFER_SET_PHYSICAL_WIDTH_HEIGHT = 0x00048003, + RPI_FIRMWARE_FRAMEBUFFER_SET_VIRTUAL_WIDTH_HEIGHT = 0x00048004, + RPI_FIRMWARE_FRAMEBUFFER_SET_DEPTH = 0x00048005, + RPI_FIRMWARE_FRAMEBUFFER_SET_PIXEL_ORDER = 0x00048006, + RPI_FIRMWARE_FRAMEBUFFER_SET_ALPHA_MODE = 0x00048007, + RPI_FIRMWARE_FRAMEBUFFER_SET_VIRTUAL_OFFSET = 0x00048009, + RPI_FIRMWARE_FRAMEBUFFER_SET_OVERSCAN = 0x0004800a, + RPI_FIRMWARE_FRAMEBUFFER_SET_PALETTE = 0x0004800b, + + RPI_FIRMWARE_GET_COMMAND_LINE = 0x00050001, + RPI_FIRMWARE_GET_DMA_CHANNELS = 0x00060001, +}; + +int rpi_firmware_property(struct rpi_firmware *fw, + u32 tag, void *data, size_t len); +int rpi_firmware_property_list(struct rpi_firmware *fw, + void *data, size_t tag_size); +struct rpi_firmware *rpi_firmware_get(struct device_node *firmware_node); +void rpi_firmware_put(struct rpi_firmware *fw); -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html