From 8fa30a396f39ba950fa8a5251e1356368cdcf5d1 Mon Sep 17 00:00:00 2001
From: TomAwezome <sonidd1@yahoo.com>
Date: Mon, 29 Aug 2022 00:24:45 -0400
Subject: [PATCH] Unhardcode BOOT_RAM_LIMIT, patch via kernel headers.

---
 src/Kernel/KStart16.ZC  | 2 ++
 src/Kernel/KStart32.ZC  | 2 +-
 src/Kernel/KStart64.ZC  | 2 +-
 src/Kernel/KernelA.HH   | 1 +
 zealbooter/zealbooter.c | 3 +++
 5 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/src/Kernel/KStart16.ZC b/src/Kernel/KStart16.ZC
index 12185d1d..858b9dde 100755
--- a/src/Kernel/KStart16.ZC
+++ b/src/Kernel/KStart16.ZC
@@ -60,6 +60,8 @@ SYS_SMBIOS_ENTRY::	DU64	0;
 
 SYS_DISK_UUID::			DU64	0, 0;
 
+SYS_BOOT_STACK::	DU32	BOOT_RAM_LIMIT;
+
 #assert $$ - SYS_KERNEL == sizeof(CKernel) - sizeof(CZXE)
 
 REQUESTED_SCREEN_WIDTH:		DU16	1024;
diff --git a/src/Kernel/KStart32.ZC b/src/Kernel/KStart32.ZC
index 5893d605..5d2ae18b 100755
--- a/src/Kernel/KStart32.ZC
+++ b/src/Kernel/KStart32.ZC
@@ -88,6 +88,7 @@ CORE0_32BIT_INIT:: //Entry point for $LK,"BootRAM",A="MN:BootRAM"$.
 		BTS 	U32 [SYS_RUN_LEVEL], RLf_32BIT
 		MOV 	ESI, U32 [SYS_BOOT_PATCH_TABLE_BASE]
 		MOV 	EDI, U32 [MEM_BOOT_BASE]
+		MOV		ESP, U32 [SYS_BOOT_STACK]
 
 		MOV		AX, CGDT.ds
 		MOV		DS,  AX
@@ -95,7 +96,6 @@ CORE0_32BIT_INIT:: //Entry point for $LK,"BootRAM",A="MN:BootRAM"$.
 		MOV		FS,  AX
 		MOV		GS,  AX
 		MOV		SS,  AX
-		MOV		ESP, BOOT_RAM_LIMIT //Tmp Stack
 
         JMP @@02
 
diff --git a/src/Kernel/KStart64.ZC b/src/Kernel/KStart64.ZC
index e4317bf0..f814e440 100755
--- a/src/Kernel/KStart64.ZC
+++ b/src/Kernel/KStart64.ZC
@@ -83,7 +83,7 @@ USE64
 //************************************
 SYS_RAM_REBOOT:: //This gets copied high.  $LK,"SYS_RAM_REBOOT",A="FF:::/System/Boot/BootRAM.ZC,SYS_RAM_REBOOT:2"$
 		PUSH	U32 CGDT.ds 		//stack seg
-		PUSH	U32 BOOT_RAM_LIMIT	//stack
+		PUSH	U32 [SYS_BOOT_STACK]//stack
 		PUSH	U32 0 				//flags
 		PUSH	U32 CGDT.cs32
 		LEA 	RAX, [@@10]
diff --git a/src/Kernel/KernelA.HH b/src/Kernel/KernelA.HH
index 6ebdd8b9..56e6fd03 100755
--- a/src/Kernel/KernelA.HH
+++ b/src/Kernel/KernelA.HH
@@ -563,6 +563,7 @@ class CKernel
 	U8				sys_framebuffer_bpp;
 	U64				sys_smbios_entry;
 	U64				sys_disk_uuid[2];
+	U32				sys_boot_stack;
 };
 
 //Run-Levels
diff --git a/zealbooter/zealbooter.c b/zealbooter/zealbooter.c
index bec0d050..57c76084 100644
--- a/zealbooter/zealbooter.c
+++ b/zealbooter/zealbooter.c
@@ -111,6 +111,7 @@ struct CKernel {
 	uint16_t sys_disk_uuid_b;
 	uint16_t sys_disk_uuid_c;
 	uint8_t sys_disk_uuid_d[8];
+	uint32_t sys_boot_stack;
 } __attribute__((packed));
 
 #define BOOT_SRC_RAM 2
@@ -266,6 +267,8 @@ void _start(void) {
 
     uintptr_t boot_stack = ALIGN_UP(final_address + kernel->size + trampoline_size, 16) + boot_stack_size;
 
+	CKernel->sys_boot_stack = boot_stack;
+
     memcpy(trampoline_phys, trampoline, trampoline_size);
     memcpy((void *)final_address, CKernel, kernel->size);