[coreboot-gerrit] New patch to review for coreboot: acpi: Generate object for coreboot table region

[Duncan Laurie (dlaurie@chromium.org)]

Duncan Laurie (dlaurie at chromium.org) just uploaded a new patch set to gerrit, which you can find at https://review.coreboot.org/16056

-gerrit

commit 53e232c7c9248118851e2511f5c67d6f46b065fe
Author: Duncan Laurie <dlaurie at chromium.org>
Date:   Thu May 26 12:47:05 2016 -0700

    acpi: Generate object for coreboot table region
    
    Generate an object to describe the coreboot table region in ACPI
    with the HID "CORE0000" so it can be used by kernel drivers.
    
    To keep track of the "CORE" HID usage add them to an enum and add
    a function to generate the HID in AML:  Name (_HID, "CORExxxx")
    
    BUG=chromium:589817
    BRANCH=none
    TEST=build and boot on chell, dump SSDT to verify contents:
    
    Device (CTBL)
    {
        Name (_HID, "CORE0000")  // _HID: Hardware ID
        Name (_UID, Zero)  // _UID: Unique ID
        Method (_STA, 0, NotSerialized)  // _STA: Status
        {
            Return (0x0F)
        }
        Name (_CRS, ResourceTemplate ()  // _CRS: Current Resource Settings
        {
            Memory32Fixed (ReadOnly,
                0x7AB84000,         // Address Base
                0x00008000,         // Address Length
                )
        })
    }
    
    Change-Id: I2c681c1fee02d52b8df2e72f6f6f0b76fa9592fb
    Signed-off-by: Duncan Laurie <dlaurie at chromium.org>
---
 src/arch/x86/acpi.c                 | 27 +++++++++++++++++++++++++++
 src/arch/x86/acpigen.c              |  8 ++++++++
 src/arch/x86/include/arch/acpi.h    |  6 ++++++
 src/arch/x86/include/arch/acpigen.h |  1 +
 4 files changed, 42 insertions(+)

diff --git a/src/arch/x86/acpi.c b/src/arch/x86/acpi.c
index 5893461..4ebdcbe 100644
--- a/src/arch/x86/acpi.c
+++ b/src/arch/x86/acpi.c
@@ -307,6 +307,29 @@ static void acpi_create_tcpa(acpi_tcpa_t *tcpa)
 	header->checksum = acpi_checksum((void *)tcpa, header->length);
 }
 
+static void acpi_ssdt_write_cbtable(void)
+{
+	const struct cbmem_entry *cbtable;
+	uintptr_t base;
+	uint32_t size;
+
+	cbtable = cbmem_entry_find(CBMEM_ID_CBTABLE);
+	if (!cbtable)
+		return;
+	base = (uintptr_t)cbmem_entry_start(cbtable);
+	size = cbmem_entry_size(cbtable);
+
+	acpigen_write_device("CTBL");
+	acpigen_write_coreboot_hid(COREBOOT_ACPI_ID_CBTABLE);
+	acpigen_write_name_integer("_UID", 0);
+	acpigen_write_STA(ACPI_STATUS_DEVICE_ALL_ON);
+	acpigen_write_name("_CRS");
+	acpigen_write_resourcetemplate_header();
+	acpigen_write_mem32fixed(0, base, size);
+	acpigen_write_resourcetemplate_footer();
+	acpigen_pop_len();
+}
+
 void acpi_create_ssdt_generator(acpi_header_t *ssdt, const char *oem_table_id)
 {
 	unsigned long current = (unsigned long)ssdt + sizeof(acpi_header_t);
@@ -323,6 +346,10 @@ void acpi_create_ssdt_generator(acpi_header_t *ssdt, const char *oem_table_id)
 	ssdt->length = sizeof(acpi_header_t);
 
 	acpigen_set_current((char *) current);
+
+	/* Write object to declare coreboot tables */
+	acpi_ssdt_write_cbtable();
+
 	{
 		struct device *dev;
 		for (dev = all_devices; dev; dev = dev->next)
diff --git a/src/arch/x86/acpigen.c b/src/arch/x86/acpigen.c
index 915faac..f35fe02 100644
--- a/src/arch/x86/acpigen.c
+++ b/src/arch/x86/acpigen.c
@@ -220,6 +220,14 @@ void acpigen_write_string(const char *string)
 	acpigen_emit_string(string);
 }
 
+void acpigen_write_coreboot_hid(enum coreboot_acpi_ids id)
+{
+	char hid[9]; /* CORExxxx */
+
+	snprintf(hid, sizeof(hid), "%.4s%04u", COREBOOT_ACPI_ID, id);
+	acpigen_write_name_string("_HID", hid);
+}
+
 /*
  * The naming conventions for ACPI namespace names are a bit tricky as
  * each element has to be 4 chars wide ("All names are a fixed 32 bits.")
diff --git a/src/arch/x86/include/arch/acpi.h b/src/arch/x86/include/arch/acpi.h
index 5d08369..21dae08 100644
--- a/src/arch/x86/include/arch/acpi.h
+++ b/src/arch/x86/include/arch/acpi.h
@@ -57,6 +57,12 @@
 #define ACPI_TABLE_CREATOR	"COREBOOT"  /* Must be exactly 8 bytes long! */
 #define OEM_ID			"CORE  "    /* Must be exactly 6 bytes long! */
 #define ASLC			"CORE"      /* Must be exactly 4 bytes long! */
+#define COREBOOT_ACPI_ID	"CORE"      /* ACPI ID for coreboot HIDs */
+
+/* List of ACPI HID that use the coreboot ACPI ID */
+enum coreboot_acpi_ids {
+	COREBOOT_ACPI_ID_CBTABLE,	/* CORE0000 */
+};
 
 /* RSDP (Root System Description Pointer) */
 typedef struct acpi_rsdp {
diff --git a/src/arch/x86/include/arch/acpigen.h b/src/arch/x86/include/arch/acpigen.h
index 9035f27..f513698 100644
--- a/src/arch/x86/include/arch/acpigen.h
+++ b/src/arch/x86/include/arch/acpigen.h
@@ -63,6 +63,7 @@ void acpigen_write_name_dword(const char *name, uint32_t val);
 void acpigen_write_name_qword(const char *name, uint64_t val);
 void acpigen_write_name_byte(const char *name, uint8_t val);
 void acpigen_write_name_integer(const char *name, uint64_t val);
+void acpigen_write_coreboot_hid(enum coreboot_acpi_ids id);
 void acpigen_write_scope(const char *name);
 void acpigen_write_method(const char *name, int nargs);
 void acpigen_write_device(const char *name);