From: Michael Brown <mcb30@ipxe.org>
Date: Wed, 7 May 2025 12:07:56 +0000 (+0100)
Subject: [riscv] Move prefix system reset code to libprefix.S
X-Git-Tag: rolling/bin~319
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=72c81419b126ddc73b2c7e9a9385fcc6faa687a8;p=thirdparty%2Fipxe.git

[riscv] Move prefix system reset code to libprefix.S

Signed-off-by: Michael Brown <mcb30@ipxe.org>
---

diff --git a/src/arch/riscv/prefix/libprefix.S b/src/arch/riscv/prefix/libprefix.S
index 4d36ba9dc..1a2b992d6 100644
--- a/src/arch/riscv/prefix/libprefix.S
+++ b/src/arch/riscv/prefix/libprefix.S
@@ -608,3 +608,45 @@ enable_paging_32_done:
 	/* Ensure that transition code did not cross an alignment boundary */
 	.section ".bss.enable_paging_32_xcheck", "aw", @nobits
 	.org	. + enable_paging_32_xalign - enable_paging_32_xlen
+
+/*****************************************************************************
+ *
+ * Reset (or lock up) system
+ *
+ *****************************************************************************
+ *
+ * Reset via system via SBI, as a means of exiting from a prefix that
+ * has no other defined exit path.  If the reset fails, lock up the
+ * system since there is nothing else that can sensibly be done.
+ *
+ * This function does not require a valid stack pointer.
+ *
+ * Parameters: none
+ *
+ * Returns: n/a (does not return)
+ *
+ */
+
+/* SBI system reset extension */
+#define SBI_SRST ( ( 'S' << 24 ) | ( 'R' << 16 ) | ( 'S' << 8 ) | 'T' )
+#define SBI_SRST_SYSTEM_RESET 0x00
+#define SBI_RESET_COLD 0x00000001
+
+	.section ".prefix.reset_system", "ax", @progbits
+	.globl	reset_system
+reset_system:
+	/* Register usage: irrelevant (does not return) */
+	progress "\niPXE->SBI reset\n"
+
+	/* Attempt reset */
+	li	a7, SBI_SRST
+	li	a6, SBI_SRST_SYSTEM_RESET
+	li	a0, SBI_RESET_COLD
+	mv	a1, zero
+	ecall
+
+	/* If reset failed, lock the system */
+	progress "(reset failed)\n"
+1:	wfi
+	j	1b
+	.size	reset_system, . - reset_system
diff --git a/src/arch/riscv/prefix/sbiprefix.S b/src/arch/riscv/prefix/sbiprefix.S
index a02d66bd6..34766d53a 100644
--- a/src/arch/riscv/prefix/sbiprefix.S
+++ b/src/arch/riscv/prefix/sbiprefix.S
@@ -32,11 +32,6 @@
 	.section ".note.GNU-stack", "", @progbits
 	.text
 
-/* SBI system reset extension */
-#define SBI_SRST ( ( 'S' << 24 ) | ( 'R' << 16 ) | ( 'S' << 8 ) | 'T' )
-#define SBI_SRST_SYSTEM_RESET 0x00
-#define SBI_RESET_COLD 0x00000001
-
 /* ELF machine type */
 #define EM_RISCV 243
 
@@ -104,17 +99,7 @@ _sbi_start:
 	 * Attempt a system reset, since there is nothing else we can
 	 * viably do at this point.
 	 */
-	progress "\niPXE->SBI reset\n"
-	li	a7, SBI_SRST
-	li	a6, SBI_SRST_SYSTEM_RESET
-	li	a0, SBI_RESET_COLD
-	mv	a1, zero
-	ecall
-
-	/* If reset failed, lock the system */
-	progress "(reset failed)\n"
-1:	wfi
-	j	1b
+	j	reset_system
 	.size	_sbi_start, . - _sbi_start
 
 	/* File split information for the compressor */