drm/imagination: Add RISC-V firmware processor support

Newer PowerVR GPUs (such as the BXS-4-64 MC1) use a RISC-V firmware
processor instead of the previous MIPS or META.

The current version of this patch depends on a patch[1] which exists in
drm-misc-fixes, but has not yet made it back to drm-misc-next (the
target of this patch). That patch adds the function pvr_vm_unmap_obj()
which is used here.

[1]: https://lore.kernel.org/r/20250226-hold-drm_gem_gpuva-lock-for-unmap-v2-1-3fdacded227f@imgtec.com

Signed-off-by: Sarah Walker <sarah.walker@imgtec.com>
Reviewed-by: Frank Binns <frank.binns@imgtec.com>
Link: https://lore.kernel.org/r/20250410-sets-bxs-4-64-patch-v1-v6-14-eda620c5865f@imgtec.com
Signed-off-by: Matt Coster <matt.coster@imgtec.com>

1 files changed, 165 insertions, 0 deletions

diff --git a/drivers/gpu/drm/imagination/pvr_fw_riscv.c b/drivers/gpu/drm/imagination/pvr_fw_riscv.c
new file mode 100644
index 000000000000..fc13d483be9a
--- /dev/null
+++ b/drivers/gpu/drm/imagination/pvr_fw_riscv.c
@@ -0,0 +1,165 @@
+// SPDX-License-Identifier: GPL-2.0 OR MIT
+/* Copyright (c) 2024 Imagination Technologies Ltd. */
+
+#include "pvr_device.h"
+#include "pvr_fw.h"
+#include "pvr_fw_info.h"
+#include "pvr_fw_mips.h"
+#include "pvr_gem.h"
+#include "pvr_rogue_cr_defs.h"
+#include "pvr_rogue_riscv.h"
+#include "pvr_vm.h"
+
+#include <linux/compiler.h>
+#include <linux/delay.h>
+#include <linux/firmware.h>
+#include <linux/ktime.h>
+#include <linux/types.h>
+
+#define ROGUE_FW_HEAP_RISCV_SHIFT 25 /* 32 MB */
+#define ROGUE_FW_HEAP_RISCV_SIZE (1u << ROGUE_FW_HEAP_RISCV_SHIFT)
+
+static int
+pvr_riscv_wrapper_init(struct pvr_device *pvr_dev)
+{
+	const u64 common_opts =
+		((u64)(ROGUE_FW_HEAP_RISCV_SIZE >> FWCORE_ADDR_REMAP_CONFIG0_SIZE_ALIGNSHIFT)
+		 << ROGUE_CR_FWCORE_ADDR_REMAP_CONFIG0_SIZE_SHIFT) |
+		((u64)MMU_CONTEXT_MAPPING_FWPRIV
+		 << FWCORE_ADDR_REMAP_CONFIG0_MMU_CONTEXT_SHIFT);
+
+	u64 code_addr = pvr_fw_obj_get_gpu_addr(pvr_dev->fw_dev.mem.code_obj);
+	u64 data_addr = pvr_fw_obj_get_gpu_addr(pvr_dev->fw_dev.mem.data_obj);
+
+	/* This condition allows us to OR the addresses into the register directly. */
+	static_assert(ROGUE_CR_FWCORE_ADDR_REMAP_CONFIG1_DEVVADDR_SHIFT ==
+		      ROGUE_CR_FWCORE_ADDR_REMAP_CONFIG1_DEVVADDR_ALIGNSHIFT);
+
+	WARN_ON(code_addr & ROGUE_CR_FWCORE_ADDR_REMAP_CONFIG1_DEVVADDR_CLRMSK);
+	WARN_ON(data_addr & ROGUE_CR_FWCORE_ADDR_REMAP_CONFIG1_DEVVADDR_CLRMSK);
+
+	pvr_cr_write64(pvr_dev, ROGUE_RISCVFW_REGION_REMAP_CR(BOOTLDR_CODE),
+		       code_addr | common_opts | ROGUE_CR_FWCORE_ADDR_REMAP_CONFIG0_FETCH_EN_EN);
+
+	pvr_cr_write64(pvr_dev, ROGUE_RISCVFW_REGION_REMAP_CR(BOOTLDR_DATA),
+		       data_addr | common_opts |
+			       ROGUE_CR_FWCORE_ADDR_REMAP_CONFIG0_LOAD_STORE_EN_EN);
+
+	/* Garten IDLE bit controlled by RISC-V. */
+	pvr_cr_write64(pvr_dev, ROGUE_CR_MTS_GARTEN_WRAPPER_CONFIG,
+		       ROGUE_CR_MTS_GARTEN_WRAPPER_CONFIG_IDLE_CTRL_META);
+
+	return 0;
+}
+
+struct rogue_riscv_fw_boot_data {
+	u64 coremem_code_dev_vaddr;
+	u64 coremem_data_dev_vaddr;
+	u32 coremem_code_fw_addr;
+	u32 coremem_data_fw_addr;
+	u32 coremem_code_size;
+	u32 coremem_data_size;
+	u32 flags;
+	u32 reserved;
+};
+
+static int
+pvr_riscv_fw_process(struct pvr_device *pvr_dev, const u8 *fw,
+		     u8 *fw_code_ptr, u8 *fw_data_ptr, u8 *fw_core_code_ptr, u8 *fw_core_data_ptr,
+		     u32 core_code_alloc_size)
+{
+	struct pvr_fw_device *fw_dev = &pvr_dev->fw_dev;
+	struct pvr_fw_mem *fw_mem = &fw_dev->mem;
+	struct rogue_riscv_fw_boot_data *boot_data;
+	int err;
+
+	err = pvr_fw_process_elf_command_stream(pvr_dev, fw, fw_code_ptr, fw_data_ptr,
+						fw_core_code_ptr, fw_core_data_ptr);
+	if (err)
+		goto err_out;
+
+	boot_data = (struct rogue_riscv_fw_boot_data *)fw_data_ptr;
+
+	if (fw_mem->core_code_obj) {
+		boot_data->coremem_code_dev_vaddr = pvr_fw_obj_get_gpu_addr(fw_mem->core_code_obj);
+		pvr_fw_object_get_fw_addr(fw_mem->core_code_obj, &boot_data->coremem_code_fw_addr);
+		boot_data->coremem_code_size = pvr_fw_obj_get_object_size(fw_mem->core_code_obj);
+	}
+
+	if (fw_mem->core_data_obj) {
+		boot_data->coremem_data_dev_vaddr = pvr_fw_obj_get_gpu_addr(fw_mem->core_data_obj);
+		pvr_fw_object_get_fw_addr(fw_mem->core_data_obj, &boot_data->coremem_data_fw_addr);
+		boot_data->coremem_data_size = pvr_fw_obj_get_object_size(fw_mem->core_data_obj);
+	}
+
+	return 0;
+
+err_out:
+	return err;
+}
+
+static int
+pvr_riscv_init(struct pvr_device *pvr_dev)
+{
+	pvr_fw_heap_info_init(pvr_dev, ROGUE_FW_HEAP_RISCV_SHIFT, 0);
+
+	return 0;
+}
+
+static u32
+pvr_riscv_get_fw_addr_with_offset(struct pvr_fw_object *fw_obj, u32 offset)
+{
+	u32 fw_addr = fw_obj->fw_addr_offset + offset;
+
+	/* RISC-V cacheability is determined by address. */
+	if (fw_obj->gem->flags & PVR_BO_FW_FLAGS_DEVICE_UNCACHED)
+		fw_addr |= ROGUE_RISCVFW_REGION_BASE(SHARED_UNCACHED_DATA);
+	else
+		fw_addr |= ROGUE_RISCVFW_REGION_BASE(SHARED_CACHED_DATA);
+
+	return fw_addr;
+}
+
+static int
+pvr_riscv_vm_map(struct pvr_device *pvr_dev, struct pvr_fw_object *fw_obj)
+{
+	struct pvr_gem_object *pvr_obj = fw_obj->gem;
+
+	return pvr_vm_map(pvr_dev->kernel_vm_ctx, pvr_obj, 0, fw_obj->fw_mm_node.start,
+			  pvr_gem_object_size(pvr_obj));
+}
+
+static void
+pvr_riscv_vm_unmap(struct pvr_device *pvr_dev, struct pvr_fw_object *fw_obj)
+{
+	struct pvr_gem_object *pvr_obj = fw_obj->gem;
+
+	pvr_vm_unmap_obj(pvr_dev->kernel_vm_ctx, pvr_obj,
+			 fw_obj->fw_mm_node.start, fw_obj->fw_mm_node.size);
+}
+
+static bool
+pvr_riscv_irq_pending(struct pvr_device *pvr_dev)
+{
+	return pvr_cr_read32(pvr_dev, ROGUE_CR_IRQ_OS0_EVENT_STATUS) &
+	       ROGUE_CR_IRQ_OS0_EVENT_STATUS_SOURCE_EN;
+}
+
+static void
+pvr_riscv_irq_clear(struct pvr_device *pvr_dev)
+{
+	pvr_cr_write32(pvr_dev, ROGUE_CR_IRQ_OS0_EVENT_CLEAR,
+		       ROGUE_CR_IRQ_OS0_EVENT_CLEAR_SOURCE_EN);
+}
+
+const struct pvr_fw_defs pvr_fw_defs_riscv = {
+	.init = pvr_riscv_init,
+	.fw_process = pvr_riscv_fw_process,
+	.vm_map = pvr_riscv_vm_map,
+	.vm_unmap = pvr_riscv_vm_unmap,
+	.get_fw_addr_with_offset = pvr_riscv_get_fw_addr_with_offset,
+	.wrapper_init = pvr_riscv_wrapper_init,
+	.irq_pending = pvr_riscv_irq_pending,
+	.irq_clear = pvr_riscv_irq_clear,
+	.has_fixed_data_addr = false,
+};