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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/firmware/raspberrypi.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/firmware/raspberrypi.c')
-rw-r--r--drivers/firmware/raspberrypi.c389
1 files changed, 389 insertions, 0 deletions
diff --git a/drivers/firmware/raspberrypi.c b/drivers/firmware/raspberrypi.c
new file mode 100644
index 000000000..dba315f67
--- /dev/null
+++ b/drivers/firmware/raspberrypi.c
@@ -0,0 +1,389 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * 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/module.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/slab.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
+
+static struct platform_device *rpi_hwmon;
+static struct platform_device *rpi_clk;
+
+struct rpi_firmware {
+ struct mbox_client cl;
+ struct mbox_chan *chan; /* The property channel. */
+ struct completion c;
+ u32 enabled;
+
+ struct kref consumers;
+};
+
+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) {
+ if (wait_for_completion_timeout(&fw->c, HZ)) {
+ ret = 0;
+ } else {
+ ret = -ETIMEDOUT;
+ WARN_ONCE(1, "Firmware transaction timeout");
+ }
+ } 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)
+{
+ struct rpi_firmware_property_tag_header *header;
+ int ret;
+
+ /* Some mailboxes can use over 1k bytes. Rather than checking
+ * size and using stack or kmalloc depending on requirements,
+ * just use kmalloc. Mailboxes don't get called enough to worry
+ * too much about the time taken in the allocation.
+ */
+ void *data = kmalloc(sizeof(*header) + buf_size, GFP_KERNEL);
+
+ if (!data)
+ return -ENOMEM;
+
+ header = data;
+ header->tag = tag;
+ header->buf_size = buf_size;
+ header->req_resp_size = 0;
+ memcpy(data + sizeof(*header), tag_data, buf_size);
+
+ ret = rpi_firmware_property_list(fw, data, buf_size + sizeof(*header));
+
+ memcpy(tag_data, data + sizeof(*header), buf_size);
+
+ kfree(data);
+
+ return ret;
+}
+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,
+ &packet, sizeof(packet));
+
+ if (ret)
+ return;
+
+ /* 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
+rpi_register_hwmon_driver(struct device *dev, struct rpi_firmware *fw)
+{
+ u32 packet;
+ int ret = rpi_firmware_property(fw, RPI_FIRMWARE_GET_THROTTLED,
+ &packet, sizeof(packet));
+
+ if (ret)
+ return;
+
+ rpi_hwmon = platform_device_register_data(dev, "raspberrypi-hwmon",
+ -1, NULL, 0);
+}
+
+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);
+}
+
+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;
+
+ /*
+ * 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;
+
+ 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);
+ kfree(fw);
+ return ret;
+ }
+
+ init_completion(&fw->c);
+ kref_init(&fw->consumers);
+
+ platform_set_drvdata(pdev, fw);
+
+ rpi_firmware_print_firmware_revision(fw);
+ rpi_register_hwmon_driver(dev, fw);
+ rpi_register_clk_driver(dev);
+
+ return 0;
+}
+
+static void rpi_firmware_shutdown(struct platform_device *pdev)
+{
+ struct rpi_firmware *fw = platform_get_drvdata(pdev);
+
+ if (!fw)
+ return;
+
+ rpi_firmware_property(fw, RPI_FIRMWARE_NOTIFY_REBOOT, NULL, 0);
+}
+
+static int rpi_firmware_remove(struct platform_device *pdev)
+{
+ struct rpi_firmware *fw = platform_get_drvdata(pdev);
+
+ platform_device_unregister(rpi_hwmon);
+ rpi_hwmon = NULL;
+ platform_device_unregister(rpi_clk);
+ rpi_clk = NULL;
+
+ rpi_firmware_put(fw);
+
+ return 0;
+}
+
+/**
+ * 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;
+
+ 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);
+
+/**
+ * devm_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 *devm_rpi_firmware_get(struct device *dev,
+ struct device_node *firmware_node)
+{
+ struct rpi_firmware *fw;
+
+ fw = rpi_firmware_get(firmware_node);
+ if (!fw)
+ return NULL;
+
+ if (devm_add_action_or_reset(dev, devm_rpi_firmware_put, fw))
+ return NULL;
+
+ return fw;
+}
+EXPORT_SYMBOL_GPL(devm_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,
+ .shutdown = rpi_firmware_shutdown,
+ .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");