diff options
Diffstat (limited to 'drivers/firmware')
| -rw-r--r-- | drivers/firmware/Kconfig | 7 | ||||
| -rw-r--r-- | drivers/firmware/Makefile | 1 | ||||
| -rw-r--r-- | drivers/firmware/raspberrypi.c | 260 |
3 files changed, 268 insertions, 0 deletions
diff --git a/drivers/firmware/Kconfig b/drivers/firmware/Kconfig index d8de6a8dd4de..9e06188ce4ea 100644 --- a/drivers/firmware/Kconfig +++ b/drivers/firmware/Kconfig @@ -139,6 +139,13 @@ 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/broadcom/Kconfig" source "drivers/firmware/google/Kconfig" source "drivers/firmware/efi/Kconfig" diff --git a/drivers/firmware/Makefile b/drivers/firmware/Makefile index 000830fc6707..d20a8f7100e1 100644 --- a/drivers/firmware/Makefile +++ b/drivers/firmware/Makefile @@ -15,6 +15,7 @@ obj-$(CONFIG_FIRMWARE_MEMMAP) += memmap.o obj-$(CONFIG_QCOM_SCM) += qcom_scm.o obj-$(CONFIG_QCOM_SCM) += qcom_scm-32.o CFLAGS_qcom_scm-32.o :=$(call as-instr,.arch_extension sec,-DREQUIRES_SEC=1) +obj-$(CONFIG_RASPBERRYPI_FIRMWARE) += raspberrypi.o obj-y += broadcom/ obj-$(CONFIG_GOOGLE_FIRMWARE) += google/ diff --git a/drivers/firmware/raspberrypi.c b/drivers/firmware/raspberrypi.c new file mode 100644 index 000000000000..dd506cd3a5b8 --- /dev/null +++ b/drivers/firmware/raspberrypi.c @@ -0,0 +1,260 @@ +/* + * 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 + * @fw: Pointer to firmware structure from rpi_firmware_get(). + * @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 + * @fw: Pointer to firmware structure from rpi_firmware_get(). + * @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; +} + +/** + * rpi_firmware_get - Get pointer to rpi_firmware structure. + * @firmware_node: Pointer to the firmware Device Tree node. + * + * 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); + + if (!pdev) + return NULL; + + return platform_get_drvdata(pdev); +} +EXPORT_SYMBOL_GPL(rpi_firmware_get); + +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@anholt.net>"); +MODULE_DESCRIPTION("Raspberry Pi firmware driver"); +MODULE_LICENSE("GPL v2"); |