From: Sergiu Moga <sergiu.moga@protonmail.com>
Date: Mon, 24 Apr 2023 17:13:18 +0000 (+0300)
Subject: plat/common/acpi: Allow getting `RSDP` through `UEFI` System Table
X-Git-Tag: RELEASE-0.14.0~56
X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=b81f13cf8514195c901c9a0b668c0905c544e152;p=unikraft%2Funikraft.git

plat/common/acpi: Allow getting `RSDP` through `UEFI` System Table

First check for the presence of `RSDP` in the `UEFI` System Table's
Configuration Tables. If it does not exist, fallback on the legacy
BIOS ROM Area.

Signed-off-by: Sergiu Moga <sergiu.moga@protonmail.com>
Reviewed-by: Dragos Petre <dragos.petre27@gmail.com>
Reviewed-by: Marco Schlumpp <marco@unikraft.io>
Approved-by: Razvan Deaconescu <razvand@unikraft.io>
Tested-by: Unikraft CI <monkey@unikraft.io>
GitHub-Closes: #911
---

diff --git a/plat/common/x86/acpi.c b/plat/common/x86/acpi.c
index a9648e5da..68432b628 100644
--- a/plat/common/x86/acpi.c
+++ b/plat/common/x86/acpi.c
@@ -37,6 +37,7 @@
 #include <x86/acpi/acpi.h>
 #include <string.h>
 #include <errno.h>
+#include <kvm/efi.h>
 #include <uk/plat/common/bootinfo.h>
 
 #define RSDP10_LEN		20
@@ -137,6 +138,41 @@ static void acpi_list_tables(void)
 }
 #endif /* UK_DEBUG */
 
+static struct acpi_rsdp *acpi_get_efi_st_rsdp(void)
+{
+	struct ukplat_bootinfo *bi = ukplat_bootinfo_get();
+	uk_efi_uintn_t ct_count, i;
+	struct uk_efi_cfg_tbl *ct;
+	struct acpi_rsdp *rsdp;
+
+	UK_ASSERT(bi);
+
+	if (!bi->efi_st)
+		return NULL;
+
+	ct = ((struct uk_efi_sys_tbl *)bi->efi_st)->configuration_table;
+	ct_count = ((struct uk_efi_sys_tbl *)bi->efi_st)->number_of_table_entries;
+
+	UK_ASSERT(ct);
+	UK_ASSERT(ct_count);
+
+	rsdp = NULL;
+	for (i = 0; i < ct_count; i++)
+		if (!memcmp(&ct[i].vendor_guid, UK_EFI_ACPI20_TABLE_GUID,
+			    sizeof(ct[i].vendor_guid))) {
+			rsdp = ct[i].vendor_table;
+
+			break;
+		} else if (!memcmp(&ct[i].vendor_guid, UK_EFI_ACPI10_TABLE_GUID,
+				 sizeof(ct[i].vendor_guid))) {
+			rsdp = ct[i].vendor_table;
+		}
+
+	uk_pr_debug("ACPI RSDP present at %p\n", rsdp);
+
+	return rsdp;
+}
+
 #if defined(__X86_64__)
 static struct acpi_rsdp *acpi_get_bios_rom_rsdp(void)
 {
@@ -155,6 +191,12 @@ static struct acpi_rsdp *acpi_get_bios_rom_rsdp(void)
 
 static struct acpi_rsdp *acpi_get_rsdp(void)
 {
+	struct acpi_rsdp *rsdp;
+
+	rsdp = acpi_get_efi_st_rsdp();
+	if (rsdp)
+		return rsdp;
+
 	return acpi_get_bios_rom_rsdp();
 }
 
diff --git a/plat/kvm/include/kvm/efi.h b/plat/kvm/include/kvm/efi.h
index 0ca3c829a..88570d97c 100644
--- a/plat/kvm/include/kvm/efi.h
+++ b/plat/kvm/include/kvm/efi.h
@@ -516,6 +516,22 @@ struct uk_efi_mem_attr_tbl {
 	struct uk_efi_mem_desc entry[1];
 };
 
+#define UK_EFI_ACPI10_TABLE_GUID					\
+	(&(struct uk_efi_guid){						\
+		.b0_3 = 0xeb9d2d30,					\
+		.b4_5 = 0x2d88,						\
+		.b6_7 = 0x11d3,						\
+		.b8_15 = {0x9a, 0x16, 0x00, 0x90,			\
+			  0x27, 0x3f, 0xc1, 0x4d},			\
+	})
+#define UK_EFI_ACPI20_TABLE_GUID					\
+	(&(struct uk_efi_guid){						\
+		.b0_3 = 0x8868e871,					\
+		.b4_5 = 0xe4f1,						\
+		.b6_7 = 0x11d3,						\
+		.b8_15 = {0xbc, 0x22, 0x00, 0x80,			\
+			  0xc7, 0x3c, 0x88, 0x81},			\
+	})
 struct uk_efi_cfg_tbl {
 	struct uk_efi_guid vendor_guid;
 	void *vendor_table;