1 files changed, 94 insertions, 26 deletions

diff --git a/src/arch/amd64/acpi.c b/src/arch/amd64/acpi.c
index eb150fe..61083f4 100644
--- a/src/arch/amd64/acpi.c
+++ b/src/arch/amd64/acpi.c
@@ -5,6 +5,7 @@
 #include <stddef.h>
 
 #include "bindings.h"
+#include "serial.h"
 
 /* global state, idk a better way rn */
 struct acpi_state state;
@@ -21,7 +22,18 @@ struct acpi_header {
 	uint32_t creator_revision;
 };
 
+// root system descriptor pointer
+// ACPI 1.0
+struct rsdp {
+	char signature[8];
+	uint8_t checksum;
+	char oemid[6];
+	uint8_t revision;
+	uint32_t rsdt_addr;
+} __attribute__((packed));
+
 // eXtended system descriptor pointer
+// ACPI 2.0
 struct xsdp {
 	char signature[8];
 	uint8_t checksum;
@@ -35,13 +47,21 @@ struct xsdp {
 	uint8_t reserved[3];
 } __attribute__((packed));
 
+// root system descriptor table
+// ACPI 1.0
+struct rsdt {
+	struct acpi_header h;
+	uint64_t sdt_pointers[];
+};
 
 // eXtended system descriptor table
+// ACPI 2.0
 struct xsdt {
 	struct acpi_header h;
 	uint64_t sdt_pointers[];
 };
 
+
 // generic address structure
 struct gas {
     uint8_t address_space;
@@ -56,10 +76,10 @@ struct fadt {
     struct acpi_header h;
     uint32_t firmware_ctrl;
     uint32_t dsdt;
- 
+
     // field used in ACPI 1.0; no longer in use, for compatibility only
     uint8_t  reserved;
- 
+
     uint8_t  preferred_power_management_profile;
     uint16_t sci_interrupt;
     uint32_t smi_command_port;
@@ -92,23 +112,23 @@ struct fadt {
     uint8_t  day_alarm;
     uint8_t  month_alarm;
     uint8_t  century;
- 
+
     // reserved in ACPI 1.0; used since ACPI 2.0+
     uint16_t boot_architecture_flags;
- 
+
     uint8_t  reserved_2;
     uint32_t flags;
- 
+
     // 12 byte structure; see below for details
     struct gas reset_reg;
- 
+
     uint8_t  reset_value;
     uint8_t  reserved_3[3];
- 
+
     // 64bit pointers - Available on ACPI 2.0+
     uint64_t x_firmware_control;
     uint64_t x_dsdt;
- 
+
     struct gas x_pm1_a_event_block;
     struct gas x_pm1_b_event_block;
     struct gas x_pm1_a_control_block;
@@ -135,9 +155,11 @@ static bool checksum(uint8_t *data, size_t len) {
 }
 
 static int read_s5_addr(struct acpi_state *state) {
+	serial_out_str("a");
     uintptr_t ptr = state->fadt.dsdt;
     char *s5_addr = (void*) (ptr + 36);
-    
+	serial_out_str("a");
+
     int dsdt_len = *((int*) (ptr+1)) - 36;
     while (0 < dsdt_len--) {
        if ( memcmp(s5_addr, "_S5_", 4) == 0)
@@ -164,17 +186,29 @@ static int read_s5_addr(struct acpi_state *state) {
             state->SCI_EN = 1;
 
         } else {
-			return ACPI_S5_PARSE_ERROR;
+			return -1;
         }
     } else {
-        return ACPI_S5_PARSE_ERROR;
+        return -1;
     }
 
-	return ACPI_SUCCESS;
+	return -1;
 }
 
+static void *acpi_find_table_rsdt(struct rsdt *rsdt, const char *identifier, int ident_len) {
+	int entries = (rsdt->h.length - sizeof(rsdt->h)) / 8;
 
-static void *acpi_find_table(struct xsdt *xsdt, const char *identifier, int ident_len) {
+	for (int i = 0; i < entries; i++) {
+		struct acpi_header *h = (struct acpi_header *) (uintptr_t) rsdt->sdt_pointers[i];
+		if (!strncmp(h->signature, identifier, ident_len))
+			return (void *)h;
+	}
+
+	// TABLE NOT FOUND
+	return NULL;
+}
+
+static void *acpi_find_table_xsdt(struct xsdt *xsdt, const char *identifier, int ident_len) {
 	int entries = (xsdt->h.length - sizeof(xsdt->h)) / 8;
 
 	for (int i = 0; i < entries; i++) {
@@ -187,38 +221,72 @@ static void *acpi_find_table(struct xsdt *xsdt, const char *identifier, int iden
 	return NULL;
 }
 
-int acpi_init(void *rootsdp) {
-	struct xsdp *xsdp = (struct xsdp *) rootsdp;
+int acpi_init_rsdt(struct rsdt *rsdt) {
+	if (!checksum((uint8_t *) &rsdt->h, rsdt->h.length))
+		return -1;
+
+	struct fadt *fadt = acpi_find_table_rsdt(rsdt, "FACP", 4);
+	if (!fadt)
+		return -1;
+
+	if (!checksum((uint8_t *) &fadt->h, fadt->h.length))
+		return -1;
 
-	if (!checksum((uint8_t *)xsdp, sizeof(struct xsdp)))
-		return ACPI_MALFORMED_TABLE;
+	state.fadt = *fadt;
 
-	if (xsdp->revision != 2)
-		return ACPI_OLD_VERSION;
+	return -1;
+}
 
-	struct xsdt *xsdt = (struct xsdt *) (uintptr_t) xsdp->xsdt_addr;
+int acpi_init_xsdt(struct xsdt *xsdt) {
 	if (!checksum((uint8_t *) &xsdt->h, xsdt->h.length))
-		return ACPI_MALFORMED_TABLE;
+		return -1;
 
-	struct fadt *fadt = acpi_find_table(xsdt, "FACP", 4);
+	struct fadt *fadt = acpi_find_table_xsdt(xsdt, "FACP", 4);
 	if (!fadt)
-		return ACPI_MALFORMED_TABLE;
+		return -1;
 
 	if (!checksum((uint8_t *) &fadt->h, fadt->h.length))
-		return ACPI_MALFORMED_TABLE;
+		return -1;
 
 	state.fadt = *fadt;
 
+	return 0;
+}
+
+int acpi_init(void *rootsdp) {
+	struct rsdp *rsdp = (struct rsdp *) rootsdp;
+
+	if (!checksum((uint8_t *)rsdp, sizeof(struct xsdp)))
+		return -1;
+
+	int res;
+
+	if (rsdp->revision == 0) {
+		res = acpi_init_rsdt(
+				(struct rsdt *) (uintptr_t) rsdp->rsdt_addr
+		);
+	} else if (rsdp->revision == 2) {
+		struct xsdp *xsdp = (struct xsdp *) rsdp;
+		res = acpi_init_xsdt(
+				(struct xsdt *) (uintptr_t) xsdp->xsdt_addr
+		);
+	} else {
+		return -1;
+	}
+
+	if (res)
+		return res;
+
 	int ret = read_s5_addr(&state);
 	if (!ret)
 		return ret;
 
     outb(state.fadt.smi_command_port,state.fadt.acpi_enable);
 
-	return ACPI_SUCCESS;
+	return 0;
 }
 
 int acpi_shutdown(void) {
     outw((unsigned int) state.fadt.pm1_a_control_block, state.SLP_TYPb | state.SLP_EN);
-	return ACPI_FAILURE;
+	return -1;
 }