1 files changed, 160 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/soc/intel_rom.c b/drivers/gpu/drm/i915/soc/intel_rom.c
new file mode 100644
index 000000000000..243d98cab8c3
--- /dev/null
+++ b/drivers/gpu/drm/i915/soc/intel_rom.c
@@ -0,0 +1,160 @@
+// SPDX-License-Identifier: MIT
+/*
+ * Copyright © 2024 Intel Corporation
+ */
+
+#include "i915_drv.h"
+#include "i915_reg.h"
+
+#include "intel_rom.h"
+#include "intel_uncore.h"
+
+struct intel_rom {
+	/* for PCI ROM */
+	struct pci_dev *pdev;
+	void __iomem *oprom;
+
+	/* for SPI */
+	struct intel_uncore *uncore;
+	loff_t offset;
+
+	size_t size;
+
+	u32 (*read32)(struct intel_rom *rom, loff_t offset);
+	u16 (*read16)(struct intel_rom *rom, loff_t offset);
+	void (*read_block)(struct intel_rom *rom, void *data, loff_t offset, size_t size);
+	void (*free)(struct intel_rom *rom);
+};
+
+static u32 spi_read32(struct intel_rom *rom, loff_t offset)
+{
+	intel_uncore_write(rom->uncore, PRIMARY_SPI_ADDRESS,
+			   rom->offset + offset);
+
+	return intel_uncore_read(rom->uncore, PRIMARY_SPI_TRIGGER);
+}
+
+static u16 spi_read16(struct intel_rom *rom, loff_t offset)
+{
+	return spi_read32(rom, offset) & 0xffff;
+}
+
+struct intel_rom *intel_rom_spi(struct drm_i915_private *i915)
+{
+	struct intel_rom *rom;
+	u32 static_region;
+
+	rom = kzalloc(sizeof(*rom), GFP_KERNEL);
+	if (!rom)
+		return NULL;
+
+	rom->uncore = &i915->uncore;
+
+	static_region = intel_uncore_read(rom->uncore, SPI_STATIC_REGIONS);
+	static_region &= OPTIONROM_SPI_REGIONID_MASK;
+	intel_uncore_write(rom->uncore, PRIMARY_SPI_REGIONID, static_region);
+
+	rom->offset = intel_uncore_read(rom->uncore, OROM_OFFSET) & OROM_OFFSET_MASK;
+
+	rom->size = 0x200000;
+
+	rom->read32 = spi_read32;
+	rom->read16 = spi_read16;
+
+	return rom;
+}
+
+static u32 pci_read32(struct intel_rom *rom, loff_t offset)
+{
+	return ioread32(rom->oprom + offset);
+}
+
+static u16 pci_read16(struct intel_rom *rom, loff_t offset)
+{
+	return ioread16(rom->oprom + offset);
+}
+
+static void pci_read_block(struct intel_rom *rom, void *data,
+			   loff_t offset, size_t size)
+{
+	memcpy_fromio(data, rom->oprom + offset, size);
+}
+
+static void pci_free(struct intel_rom *rom)
+{
+	pci_unmap_rom(rom->pdev, rom->oprom);
+}
+
+struct intel_rom *intel_rom_pci(struct drm_i915_private *i915)
+{
+	struct intel_rom *rom;
+
+	rom = kzalloc(sizeof(*rom), GFP_KERNEL);
+	if (!rom)
+		return NULL;
+
+	rom->pdev = to_pci_dev(i915->drm.dev);
+
+	rom->oprom = pci_map_rom(rom->pdev, &rom->size);
+	if (!rom->oprom) {
+		kfree(rom);
+		return NULL;
+	}
+
+	rom->read32 = pci_read32;
+	rom->read16 = pci_read16;
+	rom->read_block = pci_read_block;
+	rom->free = pci_free;
+
+	return rom;
+}
+
+u32 intel_rom_read32(struct intel_rom *rom, loff_t offset)
+{
+	return rom->read32(rom, offset);
+}
+
+u16 intel_rom_read16(struct intel_rom *rom, loff_t offset)
+{
+	return rom->read16(rom, offset);
+}
+
+void intel_rom_read_block(struct intel_rom *rom, void *data,
+			  loff_t offset, size_t size)
+{
+	u32 *ptr = data;
+	loff_t index;
+
+	if (rom->read_block) {
+		rom->read_block(rom, data, offset, size);
+		return;
+	}
+
+	for (index = 0; index < size; index += 4)
+		*ptr++ = rom->read32(rom, offset + index);
+}
+
+loff_t intel_rom_find(struct intel_rom *rom, u32 needle)
+{
+	loff_t offset;
+
+	for (offset = 0; offset < rom->size; offset += 4) {
+		if (rom->read32(rom, offset) == needle)
+			return offset;
+	}
+
+	return -ENOENT;
+}
+
+size_t intel_rom_size(struct intel_rom *rom)
+{
+	return rom->size;
+}
+
+void intel_rom_free(struct intel_rom *rom)
+{
+	if (rom && rom->free)
+		rom->free(rom);
+
+	kfree(rom);
+}