drm/imagination: Add GPU ID parsing and firmware loading

Read the GPU ID register at probe time and select the correct
features/quirks/enhancements. Use the GPU ID to form the firmware
file name and load the firmware.

The features/quirks/enhancements arrays are currently hardcoded in
the driver for the supported GPUs. We are looking at moving this
information to the firmware image.

Changes since v8:
- Corrected license identifiers

Changes since v7:
- Fix kerneldoc for pvr_device_info_set_enhancements()

Changes since v5:
- Add BRN 71242 to device info

Changes since v4:
- Retrieve device information from firmware header
- Pull forward firmware header parsing from FW infrastructure patch
- Use devm_add_action_or_reset to release firmware

Changes since v3:
- Use drm_dev_{enter,exit}

Co-developed-by: Frank Binns <frank.binns@imgtec.com>
Signed-off-by: Frank Binns <frank.binns@imgtec.com>
Co-developed-by: Matt Coster <matt.coster@imgtec.com>
Signed-off-by: Matt Coster <matt.coster@imgtec.com>
Co-developed-by: Donald Robson <donald.robson@imgtec.com>
Signed-off-by: Donald Robson <donald.robson@imgtec.com>
Signed-off-by: Sarah Walker <sarah.walker@imgtec.com>
Link: https://lore.kernel.org/r/1ff76f7a5b45c742279c78910f8491b8a5e7f6e6.1700668843.git.donald.robson@imgtec.com
Signed-off-by: Maxime Ripard <mripard@kernel.org>

1 files changed, 145 insertions, 0 deletions

diff --git a/drivers/gpu/drm/imagination/pvr_fw.c b/drivers/gpu/drm/imagination/pvr_fw.c
new file mode 100644
index 000000000000..a9377c735c9c
--- /dev/null
+++ b/drivers/gpu/drm/imagination/pvr_fw.c
@@ -0,0 +1,145 @@
+// SPDX-License-Identifier: GPL-2.0-only OR MIT
+/* Copyright (c) 2023 Imagination Technologies Ltd. */
+
+#include "pvr_device.h"
+#include "pvr_device_info.h"
+#include "pvr_fw.h"
+
+#include <drm/drm_drv.h>
+#include <linux/firmware.h>
+#include <linux/sizes.h>
+
+#define FW_MAX_SUPPORTED_MAJOR_VERSION 1
+
+/**
+ * pvr_fw_validate() - Parse firmware header and check compatibility
+ * @pvr_dev: Device pointer.
+ *
+ * Returns:
+ *  * 0 on success, or
+ *  * -EINVAL if firmware is incompatible.
+ */
+static int
+pvr_fw_validate(struct pvr_device *pvr_dev)
+{
+	struct drm_device *drm_dev = from_pvr_device(pvr_dev);
+	const struct firmware *firmware = pvr_dev->fw_dev.firmware;
+	const struct pvr_fw_layout_entry *layout_entries;
+	const struct pvr_fw_info_header *header;
+	const u8 *fw = firmware->data;
+	u32 fw_offset = firmware->size - SZ_4K;
+	u32 layout_table_size;
+	u32 entry;
+
+	if (firmware->size < SZ_4K || (firmware->size % FW_BLOCK_SIZE))
+		return -EINVAL;
+
+	header = (const struct pvr_fw_info_header *)&fw[fw_offset];
+
+	if (header->info_version != PVR_FW_INFO_VERSION) {
+		drm_err(drm_dev, "Unsupported fw info version %u\n",
+			header->info_version);
+		return -EINVAL;
+	}
+
+	if (header->header_len != sizeof(struct pvr_fw_info_header) ||
+	    header->layout_entry_size != sizeof(struct pvr_fw_layout_entry) ||
+	    header->layout_entry_num > PVR_FW_INFO_MAX_NUM_ENTRIES) {
+		drm_err(drm_dev, "FW info format mismatch\n");
+		return -EINVAL;
+	}
+
+	if (!(header->flags & PVR_FW_FLAGS_OPEN_SOURCE) ||
+	    header->fw_version_major > FW_MAX_SUPPORTED_MAJOR_VERSION ||
+	    header->fw_version_major == 0) {
+		drm_err(drm_dev, "Unsupported FW version %u.%u (build: %u%s)\n",
+			header->fw_version_major, header->fw_version_minor,
+			header->fw_version_build,
+			(header->flags & PVR_FW_FLAGS_OPEN_SOURCE) ? " OS" : "");
+		return -EINVAL;
+	}
+
+	if (pvr_gpu_id_to_packed_bvnc(&pvr_dev->gpu_id) != header->bvnc) {
+		struct pvr_gpu_id fw_gpu_id;
+
+		packed_bvnc_to_pvr_gpu_id(header->bvnc, &fw_gpu_id);
+		drm_err(drm_dev, "FW built for incorrect GPU ID %i.%i.%i.%i (expected %i.%i.%i.%i)\n",
+			fw_gpu_id.b, fw_gpu_id.v, fw_gpu_id.n, fw_gpu_id.c,
+			pvr_dev->gpu_id.b, pvr_dev->gpu_id.v, pvr_dev->gpu_id.n, pvr_dev->gpu_id.c);
+		return -EINVAL;
+	}
+
+	fw_offset += header->header_len;
+	layout_table_size =
+		header->layout_entry_size * header->layout_entry_num;
+	if ((fw_offset + layout_table_size) > firmware->size)
+		return -EINVAL;
+
+	layout_entries = (const struct pvr_fw_layout_entry *)&fw[fw_offset];
+	for (entry = 0; entry < header->layout_entry_num; entry++) {
+		u32 start_addr = layout_entries[entry].base_addr;
+		u32 end_addr = start_addr + layout_entries[entry].alloc_size;
+
+		if (start_addr >= end_addr)
+			return -EINVAL;
+	}
+
+	fw_offset = (firmware->size - SZ_4K) - header->device_info_size;
+
+	drm_info(drm_dev, "FW version v%u.%u (build %u OS)\n", header->fw_version_major,
+		 header->fw_version_minor, header->fw_version_build);
+
+	pvr_dev->fw_version.major = header->fw_version_major;
+	pvr_dev->fw_version.minor = header->fw_version_minor;
+
+	pvr_dev->fw_dev.header = header;
+	pvr_dev->fw_dev.layout_entries = layout_entries;
+
+	return 0;
+}
+
+static int
+pvr_fw_get_device_info(struct pvr_device *pvr_dev)
+{
+	const struct firmware *firmware = pvr_dev->fw_dev.firmware;
+	struct pvr_fw_device_info_header *header;
+	const u8 *fw = firmware->data;
+	const u64 *dev_info;
+	u32 fw_offset;
+
+	fw_offset = (firmware->size - SZ_4K) - pvr_dev->fw_dev.header->device_info_size;
+
+	header = (struct pvr_fw_device_info_header *)&fw[fw_offset];
+	dev_info = (u64 *)(header + 1);
+
+	pvr_device_info_set_quirks(pvr_dev, dev_info, header->brn_mask_size);
+	dev_info += header->brn_mask_size;
+
+	pvr_device_info_set_enhancements(pvr_dev, dev_info, header->ern_mask_size);
+	dev_info += header->ern_mask_size;
+
+	return pvr_device_info_set_features(pvr_dev, dev_info, header->feature_mask_size,
+					    header->feature_param_size);
+}
+
+/**
+ * pvr_fw_validate_init_device_info() - Validate firmware and initialise device information
+ * @pvr_dev: Target PowerVR device.
+ *
+ * This function must be called before querying device information.
+ *
+ * Returns:
+ *  * 0 on success, or
+ *  * -%EINVAL if firmware validation fails.
+ */
+int
+pvr_fw_validate_init_device_info(struct pvr_device *pvr_dev)
+{
+	int err;
+
+	err = pvr_fw_validate(pvr_dev);
+	if (err)
+		return err;
+
+	return pvr_fw_get_device_info(pvr_dev);
+}