From e0c0cd55c6db38e5163971bb386c59dcf77760a4 Mon Sep 17 00:00:00 2001
From: Martin Whitaker <memtest@martin-whitaker.me.uk>
Date: Sat, 23 Apr 2022 13:25:33 +0100
Subject: [PATCH] Tidy up code for performing reset via the EFI runtime
 sevices.

Make this entirely local to hwctrl.c.
---
 app/main.c      |  9 ++-------
 system/hwctrl.c | 47 +++++++++++++++++++++++++----------------------
 system/hwctrl.h |  5 +++++
 3 files changed, 32 insertions(+), 29 deletions(-)

diff --git a/app/main.c b/app/main.c
index de8f57a..08c07c7 100644
--- a/app/main.c
+++ b/app/main.c
@@ -91,8 +91,6 @@ static int              test_stage = 0;
 // Public Variables
 //------------------------------------------------------------------------------
 
-efi_info_t  saved_efi_info;
-
 // These are exposed in test.h.
 
 uint8_t     chunk_index[MAX_CPUS];
@@ -199,6 +197,8 @@ static void global_init(void)
 
     floppy_off();
 
+    hwctrl_init();
+
     cpuid_init();
 
     screen_init();
@@ -277,11 +277,6 @@ static void global_init(void)
         reboot();
     }
 
-    boot_params_t *boot_params = (boot_params_t *)boot_params_addr;
-    if(boot_params->efi_info.loader_signature){
-        saved_efi_info = boot_params->efi_info;
-    }
-
     start_barrier = smp_alloc_barrier(1);
     run_barrier   = smp_alloc_barrier(1);
 
diff --git a/system/hwctrl.c b/system/hwctrl.c
index 0d165a5..945df87 100644
--- a/system/hwctrl.c
+++ b/system/hwctrl.c
@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: GPL-2.0
-// Copyright (C) 2020 Martin Whitaker.
+// Copyright (C) 2020-2022 Martin Whitaker.
 //
 // Derived from an extract of memtest86+ lib.c:
 //
@@ -14,39 +14,42 @@
 #include "bootparams.h"
 #include "efi.h"
 
-#include "hwctrl.h"
 #include "io.h"
 
 #include "unistd.h"
 
+#include "hwctrl.h"
+
+//------------------------------------------------------------------------------
+// Private Variables
+//------------------------------------------------------------------------------
+
+static efi_runtime_services_t   *efi_rs_table = NULL;
+
 //------------------------------------------------------------------------------
 // Public Functions
 //------------------------------------------------------------------------------
 
-extern efi_info_t saved_efi_info;
-
-static void efi_reset(uint8_t reset_type)
+void hwctrl_init(void)
 {
-    static efi_runtime_services_t *rs_table = NULL;
-
+    boot_params_t *boot_params = (boot_params_t *)boot_params_addr;
 #ifdef __x86_64__
-    if (saved_efi_info.loader_signature == EFI64_LOADER_SIGNATURE) {
-        uintptr_t system_table_addr = ((uintptr_t)saved_efi_info.sys_tab_hi << 32) | saved_efi_info.sys_tab;
+    if (boot_params->efi_info.loader_signature == EFI64_LOADER_SIGNATURE) {
+        uintptr_t system_table_addr = (uintptr_t)boot_params->efi_info.sys_tab_hi << 32 | boot_params->efi_info.sys_tab;
         if (system_table_addr != 0) {
             efi64_system_table_t *sys_table = (efi64_system_table_t *)system_table_addr;
-            rs_table = (efi_runtime_services_t *)sys_table->runtime_services;
-            rs_table->reset_system(reset_type, 0, 0);
+            efi_rs_table = (efi_runtime_services_t *)sys_table->runtime_services;
+        }
+    }
+#else
+    if (boot_params->efi_info.loader_signature == EFI32_LOADER_SIGNATURE) {
+        uintptr_t system_table_addr = boot_params->efi_info.sys_tab;
+        if (system_table_addr != 0) {
+            efi32_system_table_t *sys_table = (efi32_system_table_t *)system_table_addr;
+            efi_rs_table = (efi_runtime_services_t *)(uintptr_t)sys_table->runtime_services;
         }
     }
 #endif
-    if (saved_efi_info.loader_signature == EFI32_LOADER_SIGNATURE) {
-        uintptr_t system_table_addr = saved_efi_info.sys_tab;
-        if (system_table_addr != 0) {
-            efi32_system_table_t *sys_table = (efi32_system_table_t *)system_table_addr;
-            rs_table = (efi_runtime_services_t *)(uintptr_t)sys_table->runtime_services;
-            rs_table->reset_system(reset_type, 0, 0);
-        }
-    }
 }
 
 void reboot(void)
@@ -59,8 +62,8 @@ void reboot(void)
     usleep(50);
 
     // If we have UEFI, try EFI reset service
-    if(saved_efi_info.loader_signature) {
-        efi_reset(EFI_RESET_COLD);
+    if (efi_rs_table != NULL) {
+        efi_rs_table->reset_system(EFI_RESET_COLD, 0, 0);
         usleep(1000000);
     }
 
@@ -68,7 +71,7 @@ void reboot(void)
     outb(0xfe, 0x64);
     usleep(150000);
 
-    if(!saved_efi_info.loader_signature) {
+    if (efi_rs_table == NULL) {
         // In last resort, (very) obsolete reboot method using BIOS
         *((uint16_t *)0x472) = 0x1234;
     }
diff --git a/system/hwctrl.h b/system/hwctrl.h
index c70c2a6..7fc2f97 100644
--- a/system/hwctrl.h
+++ b/system/hwctrl.h
@@ -10,6 +10,11 @@
  * Copyright (C) 2020-2022 Martin Whitaker.
  */
 
+/**
+ * Initialises the hardware control interface.
+ */
+void hwctrl_init(void);
+
 /**
  * Reboots the machine.
  */