Completely reworked ACPI tables

I'm too exhausted right now, but I rediscovered the memory mapping issue
of my ACPI implementatio and need to fix it ASAP. Otherwise I won't be
able to use any ACPI table without causing a page fault. I have no clue
why exactly this is happening and the internet says that I shouldn't
need to memory map them. Well, I'll look into it later.

2 files changed, 139 insertions, 199 deletions

diff --git a/src/kernel/acpi/acpi.c b/src/kernel/acpi/acpi.c
index 2bb097a..b348613 100644
--- a/src/kernel/acpi/acpi.c
+++ b/src/kernel/acpi/acpi.c
@@ -1,188 +1,60 @@
 // Important specification: https://uefi.org/sites/default/files/resources/ACPI_6_2.pdf
 // HPET: https://www.intel.com/content/dam/www/public/us/en/documents/technical-specifications/software-developers-hpet-spec-1-0a.pdf
 
-#include <kernel/io/io.h>
-#include <kernel/lib/lib.h>
-#include <kernel/timer/timer.h>
-#include <kernel/acpi/acpi.h>
 #include <stddef.h>
 #include <kernel/system.h>
+#include <kernel/multiboot.h>
+#include <kernel/io/io.h>
+#include <kernel/lib/lib.h>
+#include <kernel/lib/stdlib.h>
 #include <kernel/lib/stdio.h>
+#include <kernel/acpi/acpi.h>
+#include <kernel/memory/paging.h>
 
-struct FADT *fadt;
-uint32_t *SMI_CMD;
-char ACPI_ENABLE;
-char ACPI_DISABLE;
-uint32_t *PM1a_CNT;
-uint32_t *PM1b_CNT;
-int SLP_TYPa;
-int SLP_TYPb;
-int SLP_EN;
-int SCI_EN;
-char PM1_CNT_LEN;
-
-unsigned int *acpi_check_rsd_ptr(unsigned int *ptr)
-{
-	char *sig = "RSD PTR ";
-	struct RSD_ptr *rsdp = (struct RSD_ptr *)ptr;
-	char *bptr;
-	char check = 0;
-	unsigned int i;
-
-	if (memcmp(sig, rsdp, 8) == 0) {
-		bptr = (char *)ptr;
-		for (i = 0; i < sizeof(struct RSD_ptr); i++) {
-			check += *bptr;
-			bptr++;
-		}
-
-		if (check == 0) {
-			return (unsigned int *)rsdp->rsdt_address;
-		}
-	}
-
-	return NULL;
-}
+struct rsdt *rsdt;
+struct fadt *fadt;
+struct hpet *hpet;
+struct apic *apic;
 
-unsigned int *acpi_get_rsd_ptr()
+void acpi_init(struct rsdp *rsdp)
 {
-	unsigned int *addr;
-	unsigned int *rsdp;
-
-	for (addr = (unsigned int *)0x000E0000; (int)addr < 0x00100000;
-	     addr += 0x10 / sizeof(addr)) {
-		rsdp = acpi_check_rsd_ptr(addr);
-		if (rsdp != NULL)
-			return rsdp;
-	}
-
-	int ebda = *((short *)0x40E);
-	ebda = ebda * 0x10 & 0x000FFFFF;
-
-	for (addr = (unsigned int *)ebda; (int)addr < ebda + 1024; addr += 0x10 / sizeof(addr)) {
-		rsdp = acpi_check_rsd_ptr(addr);
-		if (rsdp != NULL)
-			return rsdp;
-	}
-
-	return NULL;
-}
-
-int acpi_enable()
-{
-	if ((inw((uint16_t)(unsigned int)PM1a_CNT) & SCI_EN) == 0) {
-		if (SMI_CMD != 0 && ACPI_ENABLE != 0) {
-			outb((uint16_t)(unsigned int)SMI_CMD, (uint8_t)ACPI_ENABLE); // Enable ACPI
-			// Try 3s until ACPI is enabled
-			int i;
-			for (i = 0; i < 300; i++) {
-				if ((inw((uint16_t)(unsigned int)PM1a_CNT) & SCI_EN) == 1)
-					break;
-				timer_wait(1);
-			}
-			if (PM1b_CNT != 0)
-				for (; i < 300; i++) {
-					if ((inw((uint16_t)(unsigned int)PM1b_CNT) & SCI_EN) == 1)
-						break;
-					timer_wait(1);
-				}
-			if (i < 300) {
-				return 0; // Successfully enabled ACPI
-			} else {
-				warn("ACPI couldn't be enabled!");
-				return -1; // ACPI couldn't be enabled
+	// TODO: Fix usage of ACPI tables after paging!
+	if (strncmp(rsdp->signature, "RSD PTR ", 8) == 0) {
+		rsdt = (struct rsdt *)rsdp->rsdt_address;
+		int entries = (rsdt->header.length - sizeof(rsdt->header)) / 4;
+
+		for (int i = 0; i < entries; i++) {
+			struct sdt_header *header = (struct sdt_header *)rsdt->sdt_pointer[i];
+			if (strncmp(header->signature, "FACP", 4) == 0) {
+				info("Found FADT");
+				fadt = (struct fadt *)header;
+			} else if (strncmp(header->signature, "HPET", 4) == 0) {
+				info("Found HPET");
+				hpet = (struct hpet *)header;
+			} else if (strncmp(header->signature, "APIC", 4) == 0) {
+				info("Found MADT");
+				apic = (struct apic *)header;
 			}
-		} else {
-			warn("ACPI is not supported!");
-			return -1; // ACPI is not supported
 		}
 	} else {
-		warn("ACPI was already enabled!");
-		return 0; // ACPI was already enabled
+		warn("Wrong RSD signature!");
 	}
 }
 
-int acpi_install()
+void acpi_old_init(struct multiboot_tag_old_acpi *tag)
 {
-	unsigned int *ptr = acpi_get_rsd_ptr();
-
-	int success = 0;
-
-	if (ptr != NULL && memcmp(ptr, "RSDT", 4) == 0) {
-		int entries = *(ptr + 1);
-		entries = (entries - 36) / 4;
-		ptr += 36 / 4;
-
-		while (0 < entries--) {
-			if (memcmp((unsigned int *)*ptr, "FACP", 4) == 0) {
-				fadt = (struct FADT
-						*)*ptr; // TODO: Allocate ACPI tables after paging (page fault)!
-				if (memcmp((unsigned int *)fadt->DSDT, "DSDT", 4) == 0) {
-					char *S5Addr = (char *)fadt->DSDT + 36;
-					int dsdt_length = (int)(*(fadt->DSDT + 1) - 36);
-					while (0 < dsdt_length--) {
-						if (memcmp(S5Addr, "_S5_", 4) == 0)
-							break;
-						S5Addr++;
-					}
-					if (dsdt_length > 0) {
-						// TODO: Implement device detection via DSDT ACPI (p199 -> AML)
-						if ((*(S5Addr - 1) == 0x08 ||
-						     (*(S5Addr - 2) == 0x08 &&
-						      *(S5Addr - 1) == '\\')) &&
-						    *(S5Addr + 4) == 0x12) {
-							S5Addr += 5;
-							S5Addr += ((*S5Addr & 0xC0) >> 6) + 2;
-
-							if (*S5Addr == 0x0A)
-								S5Addr++;
-							SLP_TYPa = *(S5Addr) << 10;
-							S5Addr++;
-
-							if (*S5Addr == 0x0A)
-								S5Addr++;
-							SLP_TYPb = *(S5Addr) << 10;
-
-							SMI_CMD = fadt->SMI_CMD;
-
-							ACPI_ENABLE = fadt->ACPI_ENABLE;
-							ACPI_DISABLE = fadt->ACPI_DISABLE;
-
-							PM1a_CNT = fadt->PM1a_CNT_BLK;
-							PM1b_CNT = fadt->PM1b_CNT_BLK;
-
-							PM1_CNT_LEN = fadt->PM1_CNT_LEN;
-
-							SLP_EN = 1 << 13;
-							SCI_EN = 1;
-
-							acpi_enable();
-							vga_log("Installed ACPI");
-
-							success = 1;
-						} // Else: \_S5 parse error
-					} // Else: \_S5 not present
-				} // Else: DSDT invalid
-			}
-			if (memcmp((unsigned int *)*ptr, "HPET", 4) == 0) {
-				hpet = (struct HPET *)*ptr;
-				//log("%c%c%c%c", hpet->signature[0], hpet->signature[1],
-				//hpet->signature[2], hpet->signature[3]);
-				//log("%d", hpet->legacy_replacement);
-				//log("%d", hpet->address.address);
-			}
-			ptr++;
-		} // Else: no valid FADT present
-	} else {
-		warn("ACPI is not supported!");
-	}
+	acpi_init((struct rsdp *)tag->rsdp);
+}
 
-	return success == 1 ? 0 : -1;
+void acpi_new_init(struct multiboot_tag_new_acpi *tag)
+{
+	acpi_init((struct rsdp *)tag->rsdp);
 }
 
 void acpi_poweroff()
 {
 	cli();
+	/*
 	if (SCI_EN == 0) {
 		warn("ACPI shutdown is not supported");
 		return;
@@ -197,14 +69,20 @@ void acpi_poweroff()
 		outw(0x604, 0x2000); // QEMU
 		outw(0x4004, 0x3400); // VirtualBox
 	}
+	*/
 }
 
 void reboot()
 {
 	cli();
+	outb(fadt->reset_reg.address, fadt->reset_value);
+	halt_loop();
+
+	/* else?
 	uint8_t good = 0x02;
 	while (good & 0x02)
 		good = inb(0x64);
 	outb(0x64, 0xFE);
 	halt_loop();
+	*/
 }
diff --git a/src/kernel/acpi/acpi.h b/src/kernel/acpi/acpi.h
index 1d3905f..886dc6c 100644
--- a/src/kernel/acpi/acpi.h
+++ b/src/kernel/acpi/acpi.h
@@ -1,11 +1,14 @@
 #ifndef MELVIX_ACPI_H
 #define MELVIX_ACPI_H
 
+#include <stdint.h>
+#include <kernel/multiboot.h>
+
 /**
  * Initialize the ACP interface
- * @return 0 if successful, otherwise -1
  */
-int acpi_install();
+void acpi_old_init(struct multiboot_tag_old_acpi *tag);
+void acpi_new_init(struct multiboot_tag_new_acpi *tag);
 
 /**
  * Activate a ACPI based device reboot
@@ -17,50 +20,101 @@ void reboot();
  */
 void acpi_poweroff();
 
-struct RSD_ptr {
-	char signature[8];
-	char checksum;
-	char oem_id[6];
-	char revision;
-	uint32_t *rsdt_address;
-};
-
-struct FADT {
-	char signature[4];
-	uint32_t length;
-	char unneded1[40 - 8];
-	uint32_t *DSDT;
-	char unneded2[48 - 44];
-	uint32_t *SMI_CMD;
-	char ACPI_ENABLE;
-	char ACPI_DISABLE;
-	char unneded3[64 - 54];
-	uint32_t *PM1a_CNT_BLK;
-	uint32_t *PM1b_CNT_BLK;
-	char unneded4[89 - 72];
-	char PM1_CNT_LEN;
-	char unneeded5[18];
-	char century;
-};
-
 struct address_structure {
 	uint8_t address_space_id;
 	uint8_t register_bit_width;
 	uint8_t register_bit_offset;
 	uint8_t reserved;
 	uint64_t address;
-} __attribute__((packed));
+};
+
+struct rsdp {
+	char signature[8];
+	char checksum;
+	char oem_id[6];
+	char revision;
+	uint32_t *rsdt_address;
+};
 
-struct HPET {
+struct sdt_header {
 	char signature[4];
 	uint32_t length;
 	uint8_t revision;
 	uint8_t checksum;
-	char oemid[6];
-	uint64_t oem_tableid;
+	char oem_id[6];
+	char oem_table_id[8];
 	uint32_t oem_revision;
 	uint32_t creator_id;
 	uint32_t creator_revision;
+};
+
+struct rsdt {
+	struct sdt_header header;
+	uint32_t sdt_pointer[0];
+};
+
+struct xsdt {
+	struct sdt_header header;
+	uint32_t sdt_pointer[0];
+};
+
+struct fadt {
+	struct sdt_header header;
+	uint32_t firmware_ctl;
+	uint32_t dsdt;
+	uint8_t reserved;
+	uint8_t preferred_power_management;
+	uint16_t sci_interrupt;
+	uint32_t smi_commandPort;
+	uint8_t acpi_enable;
+	uint8_t acpi_disable;
+	uint8_t S4BIOS_req;
+	uint8_t PSTATE_control;
+	uint32_t PM1a_event_block;
+	uint32_t PM1b_event_block;
+	uint32_t PM1a_control_block;
+	uint32_t PM1b_control_block;
+	uint32_t PM2_control_block;
+	uint32_t PM_timer_block;
+	uint32_t GPE0_block;
+	uint32_t GPE1_block;
+	uint8_t PM1_event_length;
+	uint8_t PM1_control_length;
+	uint8_t PM2_control_length;
+	uint8_t PM_timer_length;
+	uint8_t GPE0_length;
+	uint8_t GPE1_length;
+	uint8_t GPE1_base;
+	uint8_t C_state_control;
+	uint16_t worst_C2_latency;
+	uint16_t worst_C3_latency;
+	uint16_t flush_size;
+	uint16_t flush_stride;
+	uint8_t duty_offset;
+	uint8_t duty_width;
+	uint8_t day_alarm;
+	uint8_t month_alarm;
+	uint8_t century;
+	uint16_t boot_architecture_flags; // Reserved in 1.0
+	uint8_t reserved2;
+	uint32_t flags;
+	struct address_structure reset_reg;
+	uint8_t reset_value;
+	uint8_t reserved3[3];
+	uint64_t x_firmware_control; // Reserved in 1.0
+	uint64_t x_dsdt; // Reserved in 1.0
+	struct address_structure x_PM1a_event_block;
+	struct address_structure x_PM1b_event_block;
+	struct address_structure x_PM1a_control_block;
+	struct address_structure x_PM1b_control_block;
+	struct address_structure x_PM2_control_block;
+	struct address_structure x_PM_timer_block;
+	struct address_structure x_GPE0_block;
+	struct address_structure x_GPE1_block;
+};
+
+struct hpet {
+	struct sdt_header header;
 	uint8_t hardware_rev_id;
 	uint8_t comparator_count : 5;
 	uint8_t counter_size : 1;
@@ -71,10 +125,18 @@ struct HPET {
 	uint8_t hpet_number;
 	uint16_t minimum_tick;
 	uint8_t page_protection;
-} __attribute__((packed));
+};
 
-struct FADT *fadt;
+struct madt {
+	struct sdt_header header;
+	uint32_t address;
+	uint32_t flags;
+	// Interrupt devices...
+};
 
-struct HPET *hpet;
+struct rsdt *rsdt;
+struct fadt *fadt;
+struct hpet *hpet;
+struct madt *madt;
 
-#endif
\ No newline at end of file
+#endif