arm64: Discover UART device from ACPI.

Change-Id: I4e97b05dcfcaf6abddff81fbbf676c38fe337775
Reviewed-on: https://review.haiku-os.org/c/haiku/+/5271
Tested-by: Commit checker robot <no-reply+buildbot@haiku-os.org>
Reviewed-by: Adrien Destugues <pulkomandy@pulkomandy.tk>

headers/private/kernel/acpi.h

@@ -10,6 +10,7 @@
 #define ACPI_RSDT_SIGNATURE		"RSDT"
 #define ACPI_XSDT_SIGNATURE		"XSDT"
 #define ACPI_MADT_SIGNATURE		"APIC"
+#define ACPI_SPCR_SIGNATURE		"SPCR"
 
 #define ACPI_LOCAL_APIC_ENABLED	0x01
 
@@ -202,5 +203,41 @@ typedef struct acpi_local_x2_apic_nmi {
 	uint8	reserved3;				/* reserved (must be set to zero) */
 } _PACKED acpi_local_x2_apic_nmi;
 
+typedef struct acpi_gas {
+	uint8 address_space_id;
+	uint8 bit_width;
+	uint8 bit_offset;
+	uint8 access_size;
+	uint64 address;
+} _PACKED acpi_gas;
+
+typedef struct acpi_spcr {
+	acpi_descriptor_header header;
+	uint32 interface_type;
+	acpi_gas base_address;
+	uint8 interrupt_type;
+	uint8 irq;
+	uint32 gisv;
+	uint8 baud;
+	uint8 parity;
+	uint8 stop_bits;
+	uint8 flow_control;
+	uint8 terminal_type;
+	uint8 language;
+	uint16 pci_device_id;
+	uint16 pci_vendor_id;
+	uint8 pci_bus_num;
+	uint8 pci_vendor_num;
+	uint8 pci_function_num;
+	uint32 pci_flags;
+	uint8 pci_segment;
+	uint32 clock;
+} _PACKED acpi_spcr;
+
+enum {
+	ACPI_SPCR_INTERFACE_TYPE_16550 = 0,
+	ACPI_SPCR_INTERFACE_TYPE_PL011 = 3,
+};
+
 
 #endif	/* _KERNEL_ACPI_H */

headers/private/kernel/boot/platform/efi/arch_acpi.h

@@ -0,0 +1,15 @@
+/*
+ * Copyright 2021 Haiku, Inc. All rights reserved.
+ * Distributed under the terms of the MIT License.
+ */
+#ifndef KERNEL_BOOT_PLATFORM_EFI_ARCH_ACPI_H
+#define KERNEL_BOOT_PLATFORM_EFI_ARCH_ACPI_H
+
+
+#include <SupportDefs.h>
+
+
+void arch_handle_acpi(void);
+
+
+#endif /* KERNEL_BOOT_PLATFORM_EFI_ARCH_ACPI_H */

src/system/boot/platform/efi/acpi.cpp

@@ -17,6 +17,7 @@
 #include <KernelExport.h>
 #include <SupportDefs.h>
 
+#include <arch_acpi.h>
 #include <boot/stage2.h>
 #include <boot/platform.h>
 #include <boot/stdio.h>
@@ -195,6 +196,12 @@ acpi_find_table(const char* signature)
 }
 
 
+void __attribute__((weak))
+arch_handle_acpi()
+{
+}
+
+
 void
 acpi_init()
 {
@@ -213,6 +220,7 @@ acpi_init()
 
 		if (rsdp != NULL && acpi_check_rsdt(rsdp) == B_OK) {
 			gKernelArgs.arch_args.acpi_root = rsdp;
+			arch_handle_acpi();
 			break;
 		}
 	}

src/system/boot/platform/efi/arch/arm64/Jamfile

@@ -24,12 +24,13 @@ for platform in [ MultiBootSubDirSetup efi ] {
 		exceptions.S
 		cache.S
 		relocation_func.cpp
+		arch_acpi.cpp
+		arch_cache.cpp
+		arch_dtb.cpp
 		arch_mmu.cpp
 		arch_smp.cpp
 		arch_start.cpp
 		arch_timer.cpp
-		arch_cache.cpp
-		arch_dtb.cpp
 		;
 
 	BootMergeObject boot_platform_efi_arm64.o :

src/system/boot/platform/efi/arch/arm64/arch_acpi.cpp

@@ -0,0 +1,52 @@
+/*
+ * Copyright 2019-2022 Haiku, Inc. All rights reserved.
+ * Released under the terms of the MIT License.
+ */
+
+#include "string.h"
+
+#include <boot/platform.h>
+#include <boot/stage2.h>
+#include <arch_acpi.h>
+
+#include "serial.h"
+#include "acpi.h"
+
+#include <arch/arm/arch_uart_pl011.h>
+#include <arch/generic/debug_uart_8250.h>
+
+
+static void arch_acpi_get_uart_pl011(const uart_info &uart)
+{
+	static char sUART[sizeof(ArchUARTPL011)];
+	gUART = new(sUART) ArchUARTPL011(uart.regs.start,
+		uart.clock != 0 ? uart.clock : 0x16e3600);
+}
+
+
+void
+arch_handle_acpi()
+{
+	acpi_spcr *spcr = (acpi_spcr*)acpi_find_table(ACPI_SPCR_SIGNATURE);
+	if (spcr != NULL) {
+		uart_info &uart = gKernelArgs.arch_args.uart;
+
+		if (spcr->interface_type == ACPI_SPCR_INTERFACE_TYPE_PL011) {
+			strcpy(uart.kind, UART_KIND_PL011);
+		} else if (spcr->interface_type == ACPI_SPCR_INTERFACE_TYPE_16550) {
+			strcpy(uart.kind, UART_KIND_8250);
+		}
+
+		uart.regs.start = spcr->base_address.address;
+		uart.regs.size = B_PAGE_SIZE;
+		uart.irq = spcr->gisv;
+		uart.clock = spcr->clock;
+
+		if (spcr->interface_type == ACPI_SPCR_INTERFACE_TYPE_PL011) {
+			arch_acpi_get_uart_pl011(uart);
+		}
+
+		dprintf("discovered uart from acpi: base=%lx, irq=%u, clock=%lu\n",
+			uart.regs.start, uart.irq, uart.clock);
+	}
+}

src/system/boot/platform/efi/dtb.cpp

@@ -564,9 +564,6 @@ dtb_init()
 	efi_configuration_table *table = kSystemTable->ConfigurationTable;
 	size_t entries = kSystemTable->NumberOfTableEntries;
 
-	// Ensure uart is empty before we scan for one
-	memset(&gKernelArgs.arch_args.uart, 0, sizeof(uart_info));
-
 	INFO("Probing for device trees from UEFI...\n");
 
 	// Try to find an FDT