drm/i915: Introduce intel_cpu_info.c for CPU IDs

Having similar naming convention in intel-family.h and intel_device_info.h
results in redefinition of a few platforms. Define CPU IDs in its own file
to avoid this.

v3: Move file out of gt directory, add kernel doc (Riana)
Rephrase file description (Jani)

Signed-off-by: Raag Jadav <[e-mail]>
Acked-by: Jani Nikula <[e-mail]>
Reviewed-by: Riana Tauro <[e-mail]>
Reviewed-by: Andi Shyti <[e-mail]>
Signed-off-by: Andi Shyti <[e-mail]>
Link: https://patchwork.freedesktop.org/patch/msgid/[e-mail]

drivers/gpu/drm/i915/Makefile

···
 	i915_sysfs.o \
 	i915_utils.o \
 	intel_clock_gating.o \
+	intel_cpu_info.o \
 	intel_device_info.o \
 	intel_memory_region.o \
 	intel_pcode.o \

drivers/gpu/drm/i915/intel_cpu_info.c

···
+// SPDX-License-Identifier: MIT
+/*
+ * Copyright © 2024 Intel Corporation
+ *
+ * Avoid INTEL_<PLATFORM> name collisions between asm/intel-family.h and
+ * intel_device_info.h by having a separate file.
+ */
+
+#include "intel_cpu_info.h"
+
+#ifdef CONFIG_X86
+#include <asm/cpu_device_id.h>
+#include <asm/intel-family.h>
+
+static const struct x86_cpu_id g8_cpu_ids[] = {
+	X86_MATCH_VFM(INTEL_ALDERLAKE,		NULL),
+	X86_MATCH_VFM(INTEL_ALDERLAKE_L,	NULL),
+	X86_MATCH_VFM(INTEL_COMETLAKE,		NULL),
+	X86_MATCH_VFM(INTEL_KABYLAKE,		NULL),
+	X86_MATCH_VFM(INTEL_KABYLAKE_L,		NULL),
+	X86_MATCH_VFM(INTEL_RAPTORLAKE,		NULL),
+	X86_MATCH_VFM(INTEL_RAPTORLAKE_P,	NULL),
+	X86_MATCH_VFM(INTEL_RAPTORLAKE_S,	NULL),
+	X86_MATCH_VFM(INTEL_ROCKETLAKE,		NULL),
+	{}
+};
+
+/**
+ * intel_match_g8_cpu - match current CPU against g8_cpu_ids
+ *
+ * This matches current CPU against g8_cpu_ids, which are applicable
+ * for G8 workaround.
+ *
+ * Returns: %true if matches, %false otherwise.
+ */
+bool intel_match_g8_cpu(void)
+{
+	return x86_match_cpu(g8_cpu_ids);
+}
+#else /* CONFIG_X86 */
+
+bool intel_match_g8_cpu(void) { return false; }
+
+#endif /* CONFIG_X86 */

drivers/gpu/drm/i915/intel_cpu_info.h

···
+/* SPDX-License-Identifier: MIT */
+/*
+ * Copyright © 2024 Intel Corporation
+ */
+
+#ifndef _INTEL_CPU_INFO_H_
+#define _INTEL_CPU_INFO_H_
+
+#include <linux/types.h>
+
+bool intel_match_g8_cpu(void);
+
+#endif /* _INTEL_CPU_INFO_H_ */