Merge tag 'armsoc-drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc

Pull ARM SoC driver updates from Olof Johansson:
 "As we've enabled multiplatform kernels on ARM, and greatly done away
  with the contents under arch/arm/mach-*, there's still need for
  SoC-related drivers to go somewhere.

  Many of them go in through other driver trees, but we still have
  drivers/soc to hold some of the "doesn't fit anywhere" lowlevel code
  that might be shared between ARM and ARM64 (or just in general makes
  sense to not have under the architecture directory).

  This branch contains mostly such code:

   - Drivers for qualcomm SoCs for SMEM, SMD and SMD-RPM, used to
     communicate with power management blocks on these SoCs for use by
     clock, regulator and bus frequency drivers.

   - Allwinner Reduced Serial Bus driver, again used to communicate with
     PMICs.

   - Drivers for ARM's SCPI (System Control Processor).  Not to be
     confused with PSCI (Power State Coordination Interface).  SCPI is
     used to communicate with the assistant embedded cores doing power
     management, and we have yet to see how many of them will implement
     this for their hardware vs abstracting in other ways (or not at all
     like in the past).

   - To make confusion between SCPI and PSCI more likely, this release
     also includes an update of PSCI to interface version 1.0.

   - Rockchip support for power domains.

   - A driver to talk to the firmware on Raspberry Pi"

* tag 'armsoc-drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (57 commits)
  soc: qcom: smd-rpm: Correct size of outgoing message
  bus: sunxi-rsb: Add driver for Allwinner Reduced Serial Bus
  bus: sunxi-rsb: Add Allwinner Reduced Serial Bus (RSB) controller bindings
  ARM: bcm2835: add mutual inclusion protection
  drivers: psci: make PSCI 1.0 functions initialization version dependent
  dt-bindings: Correct paths in Rockchip power domains binding document
  soc: rockchip: power-domain: don't try to print the clock name in error case
  soc: qcom/smem: add HWSPINLOCK dependency
  clk: berlin: add cpuclk
  ARM: berlin: dts: add CLKID_CPU for BG2Q
  ARM: bcm2835: Add the Raspberry Pi firmware driver
  soc: qcom: smem: Move RPM message ram out of smem DT node
  soc: qcom: smd-rpm: Correct the active vs sleep state flagging
  soc: qcom: smd: delete unneeded of_node_put
  firmware: qcom-scm: build for correct architecture level
  soc: qcom: smd: Correct SMEM items for upper channels
  qcom-scm: add missing prototype for qcom_scm_is_available()
  qcom-scm: fix endianess issue in __qcom_scm_is_call_available
  soc: qcom: smd: Reject send of too big packets
  soc: qcom: smd: Handle big endian CPUs
  ...

1 files changed, 260 insertions, 0 deletions

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");