[coreboot] [patch 7/7] Dynamically generate PNP0C02 mainboard resources in SSDT

Tobias Diedrich ranma+coreboot at tdiedrich.de
Tue Nov 16 18:41:41 CET 2010


Dynamically generate PNP0C02 mainboard resources in SSDT

Updated patch with improved comments and small bugfix (use same
value for min and max on io resource).

While adding the area between TOM1 and 4GB to \SB.PCI0._CRS seems to be the
easiest way to get both Linux and Windows happy, it is not quite correct
because reserved areas like APIC, MMCONF etc. ranges need to be excluded.

This is a proof of concept patch for the M2V board that dynamically creates a
ResourceTemplate() containing these in the SSDT and adds a corresponding
PNP0C02 device to the DSDT.

All resources that have IORESOURCE_RESERVE and (IORESOURCE_MEM or IORESOURCE_IO) set
are added.

Here applied on top of the "Ranges unavailable for PCI BARs should be marked as
reserved in the E820 memory map, in case the OS wants to change the BARs"
patch, which adds the IORESOURCE_RESERVE flag to via k8t890/vt8237
apic/mmconf/bios resources.

coreboot log excerpt:
|ACPI:    * SSDT
|processor_brand=AMD Athlon(tm) 64 Processor 3200+
|Pstates Algorithm ...
|Pstate_freq[0] = 2000MHz        Pstate_vid[0] = 8       Pstate_volt[0] = 1350mv Pstate_power[0] = 62000mw
|Pstate_freq[1] = 1800MHz        Pstate_vid[1] = 10      Pstate_volt[1] = 1300mv Pstate_power[1] = 51743mw
|Pstate_freq[2] = 1000MHz        Pstate_vid[2] = 18      Pstate_volt[2] = 1100mv Pstate_power[2] = 20581mw
|m2v_write_mainboard_resources()
|Adding M2V reserved resources
|acpigen_add_mainboard_rsvd_mem32: base=fec00000 size=00000100
|acpigen_add_mainboard_rsvd_mem32: base=ffc00000 size=00400000
|acpigen_add_mainboard_rsvd_mem32: base=fecc0000 size=00000100
|acpigen_add_mainboard_rsvd_mem32: base=c0000000 size=10000000
|acpigen_add_mainboard_rsvd_io: base=0a20 size=0008
|ACPI: added table 7/32 Length now 64

Linux dmesg excerpt:
|ACPI: PCI Root Bridge [PCI0] (domain 0000 [bus 00-ff])
|pci_root PNP0A03:00: host bridge window [io  0x0000-0x0cf7]
|pci_root PNP0A03:00: host bridge window [io  0x0d00-0xffff]
|pci_root PNP0A03:00: host bridge window [mem 0xc0000000-0xffffffff]
|[...]
|system 00:04: [io  0x0a20-0x0a27] has been reserved
|system 00:04: [mem 0xfec00000-0xfec000ff] could not be reserved
|system 00:04: [mem 0xffc00000-0xffffffff] has been reserved
|system 00:04: [mem 0xfecc0000-0xfecc00ff] could not be reserved
|system 00:04: [mem 0xc0000000-0xcfffffff] has been reserved
|pci 0000:00:03.0: BAR 9: assigned [mem 0xd0500000-0xd06fffff 64bit pref]

Signed-off-by: Tobias Diedrich <ranma+coreboot at tdiedrich.de>

---

Index: src/mainboard/asus/m2v/acpi_tables.c
===================================================================
--- src/mainboard/asus/m2v/acpi_tables.c.orig	2010-11-16 18:37:50.000000000 +0100
+++ src/mainboard/asus/m2v/acpi_tables.c	2010-11-16 18:39:37.000000000 +0100
@@ -25,6 +25,7 @@
 #include <console/console.h>
 #include <string.h>
 #include <arch/acpi.h>
+#include <arch/acpigen.h>
 #include <arch/smp/mpspec.h>
 #include <arch/ioapic.h>
 #include <device/device.h>
@@ -88,6 +89,7 @@
 {
 	k8acpi_write_vars();
 	amd_model_fxx_generate_powernow(0, 0, 0);
+	acpigen_write_mainboard_resources("\\_SB.PCI0.MBRS", "_CRS");
 	return (unsigned long) (acpigen_get_current());
 }
 
Index: src/mainboard/asus/m2v/dsdt.asl
===================================================================
--- src/mainboard/asus/m2v/dsdt.asl.orig	2010-11-16 18:37:50.000000000 +0100
+++ src/mainboard/asus/m2v/dsdt.asl	2010-11-16 18:37:52.000000000 +0100
@@ -399,6 +399,13 @@
 				}
 			}
 
+			Device(MBRS) {
+				Name (_HID, EisaId ("PNP0C02"))
+				Name (_UID, 0x01)
+
+				External(_CRS) /* Resource Template in SSDT */
+			}
+
 			External(TOM1) /* top of memory below 4GB */
 
 			Method(_CRS, 0) {
Index: src/arch/i386/boot/acpigen.c
===================================================================
--- src/arch/i386/boot/acpigen.c.orig	2010-11-16 18:37:50.000000000 +0100
+++ src/arch/i386/boot/acpigen.c	2010-11-16 18:38:51.000000000 +0100
@@ -28,6 +28,7 @@
 #include <string.h>
 #include <arch/acpigen.h>
 #include <console/console.h>
+#include <device/device.h>
 
 static char *gencurrent;
 
@@ -372,3 +373,145 @@
 	acpigen_patch_len(len - 1);
 	return len + lenh;
 }
+
+int acpigen_write_mem32fixed(int readwrite, u32 base, u32 size)
+{
+	/*
+	 * acpi 4.0 section 6.4.3.4: 32-Bit Fixed Memory Range Descriptor
+	 * Byte 0:
+	 *   Bit7  : 1 => big item
+	 *   Bit6-0: 0000110 (0x6) => 32-bit fixed memory
+	 */
+	acpigen_emit_byte(0x86);
+	/* Byte 1+2: length (0x0009) */
+	acpigen_emit_byte(0x09);
+	acpigen_emit_byte(0x00);
+	/* bit1-7 are ignored */
+	acpigen_emit_byte(readwrite ? 0x01 : 0x00);
+	acpigen_emit_byte(base & 0xff);
+	acpigen_emit_byte((base >> 8) & 0xff);
+	acpigen_emit_byte((base >> 16) & 0xff);
+	acpigen_emit_byte((base >> 24) & 0xff);
+	acpigen_emit_byte(size & 0xff);
+	acpigen_emit_byte((size >> 8) & 0xff);
+	acpigen_emit_byte((size >> 16) & 0xff);
+	acpigen_emit_byte((size >> 24) & 0xff);
+	return 12;
+}
+
+int acpigen_write_io16(u16 min, u16 max, u8 align, u8 len, u8 decode16)
+{
+	/*
+	 * acpi 4.0 section 6.4.2.6: I/O Port Descriptor
+	 * Byte 0:
+	 *   Bit7  : 0 => small item
+	 *   Bit6-3: 1000 (0x8) => I/O port descriptor
+	 *   Bit2-0: 111 (0x7) => 7 Bytes long
+	 */
+	acpigen_emit_byte(0x47);
+	/* does the device decode all 16 or just 10 bits? */
+	/* bit1-7 are ignored */
+	acpigen_emit_byte(decode16 ? 0x01 : 0x00);
+	/* minimum base address the device may be configured for */
+	acpigen_emit_byte(min & 0xff);
+	acpigen_emit_byte((min >> 8) & 0xff);
+	/* maximum base address the device may be configured for */
+	acpigen_emit_byte(max & 0xff);
+	acpigen_emit_byte((max >> 8) & 0xff);
+	/* alignment for min base */
+	acpigen_emit_byte(align & 0xff);
+	acpigen_emit_byte(len & 0xff);
+	return 8;
+}
+
+int acpigen_write_resourcetemplate_header(void)
+{
+	int len;
+	/*
+	 * A ResourceTemplate() is a Buffer() with a
+	 * (Byte|Word|DWord) containing the length, followed by one or more
+	 * resource items, terminated by the end tag
+	 * (small item 0xf, len 1)
+	 */
+	len = acpigen_emit_byte(0x11); /* Buffer opcode */
+	len += acpigen_write_len_f();
+	len += acpigen_emit_byte(0x0b); /* Word opcode */
+	len_stack[ltop++] = acpigen_get_current();
+	len += acpigen_emit_byte(0x00);
+	len += acpigen_emit_byte(0x00);
+	return len;
+}
+
+int acpigen_write_resourcetemplate_footer(int len)
+{
+	char *p = len_stack[--ltop];
+	/*
+	 * end tag (acpi 4.0 Section 6.4.2.8)
+	 * 0x79 <checksum>
+	 * 0x00 is treated as a good checksum according to the spec
+	 * and is what iasl generates.
+	 */
+	len += acpigen_emit_byte(0x79);
+	len += acpigen_emit_byte(0x00);
+	/* patch len word */
+	p[0] = (len-6) & 0xff;
+	p[1] = ((len-6) >> 8) & 0xff;
+	/* patch len field */
+	acpigen_patch_len(len-1);
+	return 2;
+}
+
+static void acpigen_add_mainboard_rsvd_mem32(void *gp, struct device *dev,
+						struct resource *res)
+{
+	acpigen_write_mem32fixed(0, res->base, res->size);
+}
+
+static void acpigen_add_mainboard_rsvd_io(void *gp, struct device *dev,
+						struct resource *res)
+{
+	resource_t base = res->base;
+	resource_t size = res->size;
+	while (size > 0) {
+		resource_t sz = size > 255 ? 255 : size;
+		acpigen_write_io16(base, base, 0, sz, 1);
+		size -= sz;
+		base += sz;
+	}
+}
+
+int acpigen_write_mainboard_resource_template(void)
+{
+	int len;
+	char *start;
+	char *end;
+	len = acpigen_write_resourcetemplate_header();
+	start = acpigen_get_current();
+
+	/* Add reserved memory ranges */
+	search_global_resources(
+		IORESOURCE_MEM | IORESOURCE_RESERVE,
+		 IORESOURCE_MEM | IORESOURCE_RESERVE,
+		acpigen_add_mainboard_rsvd_mem32, 0);
+
+	/* Add reserved io ranges */
+	search_global_resources(
+		IORESOURCE_IO | IORESOURCE_RESERVE,
+		 IORESOURCE_IO | IORESOURCE_RESERVE,
+		acpigen_add_mainboard_rsvd_io, 0);
+
+	end = acpigen_get_current();
+	len += end-start;
+	len += acpigen_write_resourcetemplate_footer(len);
+	return len;
+}
+
+int acpigen_write_mainboard_resources(const char *scope, const char *name)
+{
+	int len;
+	len = acpigen_write_scope(scope);
+	len += acpigen_write_name(name);
+	len += acpigen_write_mainboard_resource_template();
+	acpigen_patch_len(len - 1);
+	return len;
+}
Index: src/arch/i386/include/arch/acpigen.h
===================================================================
--- src/arch/i386/include/arch/acpigen.h.orig	2010-11-16 18:37:50.000000000 +0100
+++ src/arch/i386/include/arch/acpigen.h	2010-11-16 18:39:13.000000000 +0100
@@ -46,5 +46,11 @@
 typedef enum { SW_ALL=0xfc, SW_ANY=0xfd, HW_ALL=0xfe } PSD_coord;
 int acpigen_write_PSD_package(u32 domain, u32 numprocs, PSD_coord coordtype);
 int acpigen_write_processor(u8 cpuindex, u32 pblock_addr, u8 pblock_len);
+int acpigen_write_mem32fixed(int readwrite, u32 base, u32 size);
+int acpigen_write_io16(u16 min, u16 max, u8 align, u8 len, u8 decode16);
+int acpigen_write_resourcetemplate_header(void);
+int acpigen_write_resourcetemplate_footer(int len);
+int acpigen_write_mainboard_resource_template(void);
+int acpigen_write_mainboard_resources(const char *scope, const char *name);
 
 #endif




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