x86: acpi: Add PCT and PTC tables

These are needed for the CPU tables. Add them into an x86-specific file
since we do not support them on sandbox, or include tests.

Signed-off-by: Simon Glass <sjg@chromium.org>

diff --git a/arch/x86/include/asm/acpigen.h b/arch/x86/include/asm/acpigen.h
new file mode 100644 (file)
index 0000000..c531dd6
--- /dev/null
+++ b/arch/x86/include/asm/acpigen.h
@@ -0,0 +1,35 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Generation of x86-specific ACPI tables
+ *
+ * Copyright 2020 Google LLC
+ */
+
+#ifndef __ASM_ACPIGEN_H__
+#define __ASM_ACPIGEN_H__
+
+struct acpi_ctx;
+
+/**
+ * acpigen_write_empty_pct() - Write an empty PCT
+ *
+ * See ACPI v6.3 section 8.4.6.1: _PCT (Performance Control)
+ *
+ * This writes an empty table so that CPU performance works as expected
+ *
+ * @ctx: ACPI context pointer
+ */
+void acpigen_write_empty_pct(struct acpi_ctx *ctx);
+
+/**
+ * acpigen_write_empty_ptc() - Write an empty PTC
+ *
+ * See ACPI v6.3 section 8.4.5.1: _PTC (Processor Throttling Control)
+ *
+ * This writes an empty table so that CPU performance works as expected
+ *
+ * @ctx: ACPI context pointer
+ */
+void acpigen_write_empty_ptc(struct acpi_ctx *ctx);
+
+#endif /* __ASM_ACPI_H__ */

diff --git a/arch/x86/lib/Makefile b/arch/x86/lib/Makefile
index 1185a88..f04d275 100644 (file)
--- a/arch/x86/lib/Makefile
+++ b/arch/x86/lib/Makefile
@@ -38,7 +38,7 @@ obj-y += sfi.o
 obj-y  += acpi.o
 obj-$(CONFIG_HAVE_ACPI_RESUME) += acpi_s3.o
 ifndef CONFIG_QEMU
-obj-$(CONFIG_GENERATE_ACPI_TABLE) += acpi_table.o
+obj-$(CONFIG_GENERATE_ACPI_TABLE) += acpi_table.o acpigen.o
 endif
 obj-y  += tables.o
 ifndef CONFIG_SPL_BUILD

diff --git a/arch/x86/lib/acpigen.c b/arch/x86/lib/acpigen.c
new file mode 100644 (file)
index 0000000..ea2ec2a
--- /dev/null
+++ b/arch/x86/lib/acpigen.c
@@ -0,0 +1,96 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2020 Google LLC
+ */
+
+#include <common.h>
+#include <acpi/acpigen.h>
+#include <acpi/acpi_table.h>
+#include <asm/acpigen.h>
+
+void acpigen_write_empty_pct(struct acpi_ctx *ctx)
+{
+       /*
+        * Name (_PCT, Package (0x02)
+        * {
+        *      ResourceTemplate ()
+        *      {
+        *              Register (FFixedHW,
+        *                      0x00,               // Bit Width
+        *                      0x00,               // Bit Offset
+        *                      0x0000000000000000, // Address
+        *                      ,)
+        *      },
+        *
+        *      ResourceTemplate ()
+        *      {
+        *              Register (FFixedHW,
+        *                      0x00,               // Bit Width
+        *                      0x00,               // Bit Offset
+        *                      0x0000000000000000, // Address
+        *                      ,)
+        *      }
+        * })
+        */
+       static char stream[] = {
+               /* 00000030    "0._PCT.," */
+               0x08, 0x5f, 0x50, 0x43, 0x54, 0x12, 0x2c,
+               /* 00000038    "........" */
+               0x02, 0x11, 0x14, 0x0a, 0x11, 0x82, 0x0c, 0x00,
+               /* 00000040    "........" */
+               0x7f, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+               /* 00000048    "....y..." */
+               0x00, 0x00, 0x00, 0x00, 0x79, 0x00, 0x11, 0x14,
+               /* 00000050    "........" */
+               0x0a, 0x11, 0x82, 0x0c, 0x00, 0x7f, 0x00, 0x00,
+               /* 00000058    "........" */
+               0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+               0x00, 0x79, 0x00
+       };
+       acpigen_emit_stream(ctx, stream, ARRAY_SIZE(stream));
+}
+
+void acpigen_write_empty_ptc(struct acpi_ctx *ctx)
+{
+       /*
+        * Name (_PTC, Package (0x02)
+        * {
+        *      ResourceTemplate ()
+        *      {
+        *              Register (FFixedHW,
+        *                      0x00,               // Bit Width
+        *                      0x00,               // Bit Offset
+        *                      0x0000000000000000, // Address
+        *                      ,)
+        *      },
+        *
+        *      ResourceTemplate ()
+        *      {
+        *              Register (FFixedHW,
+        *                      0x00,               // Bit Width
+        *                      0x00,               // Bit Offset
+        *                      0x0000000000000000, // Address
+        *                      ,)
+        *      }
+        * })
+        */
+       struct acpi_gen_regaddr addr = {
+               .space_id    = ACPI_ADDRESS_SPACE_FIXED,
+               .bit_width   = 0,
+               .bit_offset  = 0,
+               .access_size = 0,
+               .addrl       = 0,
+               .addrh       = 0,
+       };
+
+       acpigen_write_name(ctx, "_PTC");
+       acpigen_write_package(ctx, 2);
+
+       /* ControlRegister */
+       acpigen_write_register_resource(ctx, &addr);
+
+       /* StatusRegister */
+       acpigen_write_register_resource(ctx, &addr);
+
+       acpigen_pop_len(ctx);
+}