14e3d6065SEric Anholt /* 24e3d6065SEric Anholt * Defines interfaces for interacting wtih the Raspberry Pi firmware's 34e3d6065SEric Anholt * property channel. 44e3d6065SEric Anholt * 54e3d6065SEric Anholt * Copyright © 2015 Broadcom 64e3d6065SEric Anholt * 74e3d6065SEric Anholt * This program is free software; you can redistribute it and/or modify 84e3d6065SEric Anholt * it under the terms of the GNU General Public License version 2 as 94e3d6065SEric Anholt * published by the Free Software Foundation. 104e3d6065SEric Anholt */ 114e3d6065SEric Anholt 124e3d6065SEric Anholt #include <linux/dma-mapping.h> 134e3d6065SEric Anholt #include <linux/mailbox_client.h> 144e3d6065SEric Anholt #include <linux/module.h> 154e3d6065SEric Anholt #include <linux/of_platform.h> 164e3d6065SEric Anholt #include <linux/platform_device.h> 174e3d6065SEric Anholt #include <soc/bcm2835/raspberrypi-firmware.h> 184e3d6065SEric Anholt 194e3d6065SEric Anholt #define MBOX_MSG(chan, data28) (((data28) & ~0xf) | ((chan) & 0xf)) 204e3d6065SEric Anholt #define MBOX_CHAN(msg) ((msg) & 0xf) 214e3d6065SEric Anholt #define MBOX_DATA28(msg) ((msg) & ~0xf) 224e3d6065SEric Anholt #define MBOX_CHAN_PROPERTY 8 234e3d6065SEric Anholt 244e3d6065SEric Anholt struct rpi_firmware { 254e3d6065SEric Anholt struct mbox_client cl; 264e3d6065SEric Anholt struct mbox_chan *chan; /* The property channel. */ 274e3d6065SEric Anholt struct completion c; 284e3d6065SEric Anholt u32 enabled; 294e3d6065SEric Anholt }; 304e3d6065SEric Anholt 314e3d6065SEric Anholt static DEFINE_MUTEX(transaction_lock); 324e3d6065SEric Anholt 334e3d6065SEric Anholt static void response_callback(struct mbox_client *cl, void *msg) 344e3d6065SEric Anholt { 354e3d6065SEric Anholt struct rpi_firmware *fw = container_of(cl, struct rpi_firmware, cl); 364e3d6065SEric Anholt complete(&fw->c); 374e3d6065SEric Anholt } 384e3d6065SEric Anholt 394e3d6065SEric Anholt /* 404e3d6065SEric Anholt * Sends a request to the firmware through the BCM2835 mailbox driver, 414e3d6065SEric Anholt * and synchronously waits for the reply. 424e3d6065SEric Anholt */ 434e3d6065SEric Anholt static int 444e3d6065SEric Anholt rpi_firmware_transaction(struct rpi_firmware *fw, u32 chan, u32 data) 454e3d6065SEric Anholt { 464e3d6065SEric Anholt u32 message = MBOX_MSG(chan, data); 474e3d6065SEric Anholt int ret; 484e3d6065SEric Anholt 494e3d6065SEric Anholt WARN_ON(data & 0xf); 504e3d6065SEric Anholt 514e3d6065SEric Anholt mutex_lock(&transaction_lock); 524e3d6065SEric Anholt reinit_completion(&fw->c); 534e3d6065SEric Anholt ret = mbox_send_message(fw->chan, &message); 544e3d6065SEric Anholt if (ret >= 0) { 554e3d6065SEric Anholt wait_for_completion(&fw->c); 564e3d6065SEric Anholt ret = 0; 574e3d6065SEric Anholt } else { 584e3d6065SEric Anholt dev_err(fw->cl.dev, "mbox_send_message returned %d\n", ret); 594e3d6065SEric Anholt } 604e3d6065SEric Anholt mutex_unlock(&transaction_lock); 614e3d6065SEric Anholt 624e3d6065SEric Anholt return ret; 634e3d6065SEric Anholt } 644e3d6065SEric Anholt 654e3d6065SEric Anholt /** 664e3d6065SEric Anholt * rpi_firmware_property_list - Submit firmware property list 674e3d6065SEric Anholt * @fw: Pointer to firmware structure from rpi_firmware_get(). 684e3d6065SEric Anholt * @data: Buffer holding tags. 694e3d6065SEric Anholt * @tag_size: Size of tags buffer. 704e3d6065SEric Anholt * 714e3d6065SEric Anholt * Submits a set of concatenated tags to the VPU firmware through the 724e3d6065SEric Anholt * mailbox property interface. 734e3d6065SEric Anholt * 744e3d6065SEric Anholt * The buffer header and the ending tag are added by this function and 754e3d6065SEric Anholt * don't need to be supplied, just the actual tags for your operation. 764e3d6065SEric Anholt * See struct rpi_firmware_property_tag_header for the per-tag 774e3d6065SEric Anholt * structure. 784e3d6065SEric Anholt */ 794e3d6065SEric Anholt int rpi_firmware_property_list(struct rpi_firmware *fw, 804e3d6065SEric Anholt void *data, size_t tag_size) 814e3d6065SEric Anholt { 824e3d6065SEric Anholt size_t size = tag_size + 12; 834e3d6065SEric Anholt u32 *buf; 844e3d6065SEric Anholt dma_addr_t bus_addr; 854e3d6065SEric Anholt int ret; 864e3d6065SEric Anholt 874e3d6065SEric Anholt /* Packets are processed a dword at a time. */ 884e3d6065SEric Anholt if (size & 3) 894e3d6065SEric Anholt return -EINVAL; 904e3d6065SEric Anholt 914e3d6065SEric Anholt buf = dma_alloc_coherent(fw->cl.dev, PAGE_ALIGN(size), &bus_addr, 924e3d6065SEric Anholt GFP_ATOMIC); 934e3d6065SEric Anholt if (!buf) 944e3d6065SEric Anholt return -ENOMEM; 954e3d6065SEric Anholt 964e3d6065SEric Anholt /* The firmware will error out without parsing in this case. */ 974e3d6065SEric Anholt WARN_ON(size >= 1024 * 1024); 984e3d6065SEric Anholt 994e3d6065SEric Anholt buf[0] = size; 1004e3d6065SEric Anholt buf[1] = RPI_FIRMWARE_STATUS_REQUEST; 1014e3d6065SEric Anholt memcpy(&buf[2], data, tag_size); 1024e3d6065SEric Anholt buf[size / 4 - 1] = RPI_FIRMWARE_PROPERTY_END; 1034e3d6065SEric Anholt wmb(); 1044e3d6065SEric Anholt 1054e3d6065SEric Anholt ret = rpi_firmware_transaction(fw, MBOX_CHAN_PROPERTY, bus_addr); 1064e3d6065SEric Anholt 1074e3d6065SEric Anholt rmb(); 1084e3d6065SEric Anholt memcpy(data, &buf[2], tag_size); 1094e3d6065SEric Anholt if (ret == 0 && buf[1] != RPI_FIRMWARE_STATUS_SUCCESS) { 1104e3d6065SEric Anholt /* 1114e3d6065SEric Anholt * The tag name here might not be the one causing the 1124e3d6065SEric Anholt * error, if there were multiple tags in the request. 1134e3d6065SEric Anholt * But single-tag is the most common, so go with it. 1144e3d6065SEric Anholt */ 1154e3d6065SEric Anholt dev_err(fw->cl.dev, "Request 0x%08x returned status 0x%08x\n", 1164e3d6065SEric Anholt buf[2], buf[1]); 1174e3d6065SEric Anholt ret = -EINVAL; 1184e3d6065SEric Anholt } 1194e3d6065SEric Anholt 1204e3d6065SEric Anholt dma_free_coherent(fw->cl.dev, PAGE_ALIGN(size), buf, bus_addr); 1214e3d6065SEric Anholt 1224e3d6065SEric Anholt return ret; 1234e3d6065SEric Anholt } 1244e3d6065SEric Anholt EXPORT_SYMBOL_GPL(rpi_firmware_property_list); 1254e3d6065SEric Anholt 1264e3d6065SEric Anholt /** 1274e3d6065SEric Anholt * rpi_firmware_property - Submit single firmware property 1284e3d6065SEric Anholt * @fw: Pointer to firmware structure from rpi_firmware_get(). 1294e3d6065SEric Anholt * @tag: One of enum_mbox_property_tag. 1304e3d6065SEric Anholt * @tag_data: Tag data buffer. 1314e3d6065SEric Anholt * @buf_size: Buffer size. 1324e3d6065SEric Anholt * 1334e3d6065SEric Anholt * Submits a single tag to the VPU firmware through the mailbox 1344e3d6065SEric Anholt * property interface. 1354e3d6065SEric Anholt * 1364e3d6065SEric Anholt * This is a convenience wrapper around 1374e3d6065SEric Anholt * rpi_firmware_property_list() to avoid some of the 1384e3d6065SEric Anholt * boilerplate in property calls. 1394e3d6065SEric Anholt */ 1404e3d6065SEric Anholt int rpi_firmware_property(struct rpi_firmware *fw, 1414e3d6065SEric Anholt u32 tag, void *tag_data, size_t buf_size) 1424e3d6065SEric Anholt { 1434e3d6065SEric Anholt /* Single tags are very small (generally 8 bytes), so the 1444e3d6065SEric Anholt * stack should be safe. 1454e3d6065SEric Anholt */ 1464e3d6065SEric Anholt u8 data[buf_size + sizeof(struct rpi_firmware_property_tag_header)]; 1474e3d6065SEric Anholt struct rpi_firmware_property_tag_header *header = 1484e3d6065SEric Anholt (struct rpi_firmware_property_tag_header *)data; 1494e3d6065SEric Anholt int ret; 1504e3d6065SEric Anholt 1514e3d6065SEric Anholt header->tag = tag; 1524e3d6065SEric Anholt header->buf_size = buf_size; 1534e3d6065SEric Anholt header->req_resp_size = 0; 1544e3d6065SEric Anholt memcpy(data + sizeof(struct rpi_firmware_property_tag_header), 1554e3d6065SEric Anholt tag_data, buf_size); 1564e3d6065SEric Anholt 1574e3d6065SEric Anholt ret = rpi_firmware_property_list(fw, &data, sizeof(data)); 1584e3d6065SEric Anholt memcpy(tag_data, 1594e3d6065SEric Anholt data + sizeof(struct rpi_firmware_property_tag_header), 1604e3d6065SEric Anholt buf_size); 1614e3d6065SEric Anholt 1624e3d6065SEric Anholt return ret; 1634e3d6065SEric Anholt } 1644e3d6065SEric Anholt EXPORT_SYMBOL_GPL(rpi_firmware_property); 1654e3d6065SEric Anholt 1664e3d6065SEric Anholt static void 1674e3d6065SEric Anholt rpi_firmware_print_firmware_revision(struct rpi_firmware *fw) 1684e3d6065SEric Anholt { 1694e3d6065SEric Anholt u32 packet; 1704e3d6065SEric Anholt int ret = rpi_firmware_property(fw, 1714e3d6065SEric Anholt RPI_FIRMWARE_GET_FIRMWARE_REVISION, 1724e3d6065SEric Anholt &packet, sizeof(packet)); 1734e3d6065SEric Anholt 1744e3d6065SEric Anholt if (ret == 0) { 1754e3d6065SEric Anholt struct tm tm; 1764e3d6065SEric Anholt 1774e3d6065SEric Anholt time_to_tm(packet, 0, &tm); 1784e3d6065SEric Anholt 1794e3d6065SEric Anholt dev_info(fw->cl.dev, 1804e3d6065SEric Anholt "Attached to firmware from %04ld-%02d-%02d %02d:%02d\n", 1814e3d6065SEric Anholt tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday, 1824e3d6065SEric Anholt tm.tm_hour, tm.tm_min); 1834e3d6065SEric Anholt } 1844e3d6065SEric Anholt } 1854e3d6065SEric Anholt 1864e3d6065SEric Anholt static int rpi_firmware_probe(struct platform_device *pdev) 1874e3d6065SEric Anholt { 1884e3d6065SEric Anholt struct device *dev = &pdev->dev; 1894e3d6065SEric Anholt struct rpi_firmware *fw; 1904e3d6065SEric Anholt 1914e3d6065SEric Anholt fw = devm_kzalloc(dev, sizeof(*fw), GFP_KERNEL); 1924e3d6065SEric Anholt if (!fw) 1934e3d6065SEric Anholt return -ENOMEM; 1944e3d6065SEric Anholt 1954e3d6065SEric Anholt fw->cl.dev = dev; 1964e3d6065SEric Anholt fw->cl.rx_callback = response_callback; 1974e3d6065SEric Anholt fw->cl.tx_block = true; 1984e3d6065SEric Anholt 1994e3d6065SEric Anholt fw->chan = mbox_request_channel(&fw->cl, 0); 2004e3d6065SEric Anholt if (IS_ERR(fw->chan)) { 2014e3d6065SEric Anholt int ret = PTR_ERR(fw->chan); 2024e3d6065SEric Anholt if (ret != -EPROBE_DEFER) 2034e3d6065SEric Anholt dev_err(dev, "Failed to get mbox channel: %d\n", ret); 2044e3d6065SEric Anholt return ret; 2054e3d6065SEric Anholt } 2064e3d6065SEric Anholt 2074e3d6065SEric Anholt init_completion(&fw->c); 2084e3d6065SEric Anholt 2094e3d6065SEric Anholt platform_set_drvdata(pdev, fw); 2104e3d6065SEric Anholt 2114e3d6065SEric Anholt rpi_firmware_print_firmware_revision(fw); 2124e3d6065SEric Anholt 2134e3d6065SEric Anholt return 0; 2144e3d6065SEric Anholt } 2154e3d6065SEric Anholt 2164e3d6065SEric Anholt static int rpi_firmware_remove(struct platform_device *pdev) 2174e3d6065SEric Anholt { 2184e3d6065SEric Anholt struct rpi_firmware *fw = platform_get_drvdata(pdev); 2194e3d6065SEric Anholt 2204e3d6065SEric Anholt mbox_free_channel(fw->chan); 2214e3d6065SEric Anholt 2224e3d6065SEric Anholt return 0; 2234e3d6065SEric Anholt } 2244e3d6065SEric Anholt 2254e3d6065SEric Anholt /** 2264e3d6065SEric Anholt * rpi_firmware_get - Get pointer to rpi_firmware structure. 2274e3d6065SEric Anholt * @firmware_node: Pointer to the firmware Device Tree node. 2284e3d6065SEric Anholt * 2294e3d6065SEric Anholt * Returns NULL is the firmware device is not ready. 2304e3d6065SEric Anholt */ 2314e3d6065SEric Anholt struct rpi_firmware *rpi_firmware_get(struct device_node *firmware_node) 2324e3d6065SEric Anholt { 2334e3d6065SEric Anholt struct platform_device *pdev = of_find_device_by_node(firmware_node); 2344e3d6065SEric Anholt 2354e3d6065SEric Anholt if (!pdev) 2364e3d6065SEric Anholt return NULL; 2374e3d6065SEric Anholt 2384e3d6065SEric Anholt return platform_get_drvdata(pdev); 2394e3d6065SEric Anholt } 2404e3d6065SEric Anholt EXPORT_SYMBOL_GPL(rpi_firmware_get); 2414e3d6065SEric Anholt 2424e3d6065SEric Anholt static const struct of_device_id rpi_firmware_of_match[] = { 2434e3d6065SEric Anholt { .compatible = "raspberrypi,bcm2835-firmware", }, 2444e3d6065SEric Anholt {}, 2454e3d6065SEric Anholt }; 2464e3d6065SEric Anholt MODULE_DEVICE_TABLE(of, rpi_firmware_of_match); 2474e3d6065SEric Anholt 2484e3d6065SEric Anholt static struct platform_driver rpi_firmware_driver = { 2494e3d6065SEric Anholt .driver = { 2504e3d6065SEric Anholt .name = "raspberrypi-firmware", 2514e3d6065SEric Anholt .of_match_table = rpi_firmware_of_match, 2524e3d6065SEric Anholt }, 2534e3d6065SEric Anholt .probe = rpi_firmware_probe, 2544e3d6065SEric Anholt .remove = rpi_firmware_remove, 2554e3d6065SEric Anholt }; 2564e3d6065SEric Anholt module_platform_driver(rpi_firmware_driver); 2574e3d6065SEric Anholt 2584e3d6065SEric Anholt MODULE_AUTHOR("Eric Anholt <eric@anholt.net>"); 2594e3d6065SEric Anholt MODULE_DESCRIPTION("Raspberry Pi firmware driver"); 2604e3d6065SEric Anholt MODULE_LICENSE("GPL v2"); 261