sysadmin/ipxe
1
0
Fork 0
mirror of https://github.com/ipxe/ipxe synced 2025-12-07 18:00:28 +03:00
Code Issues Packages Projects Releases Wiki Activity

[riscv] Create macros for writing characters to the debug console

Browse Source 
Abstract out the SBI debug console calls into macros that can be
shared between print_message and print_hex_value.

Signed-off-by: Michael Brown <mcb30@ipxe.org>
This commit is contained in:
Michael Brown
2025-05-26 23:33:35 +01:00
parent 6eb51f1a6a
commit 2e8d45aeef
1 changed files with 62 additions and 17 deletions
Download Patch File Download Diff File Expand all files Collapse all files

79
src/arch/riscv/prefix/libprefix.S
View File

@@ -52,6 +52,64 @@ prefix_virt:
.dword _prefix
.size prefix_virt, . - prefix_virt
/*****************************************************************************
*
* Print character via debug console extension
*
*****************************************************************************
*
* Print a single character via the SBI DBCN extension.
*
* Parameters:
*
* a0 - Character to print
*
* Returns:
*
* a0 - Zero if character printed successfully
* a1 - Overwritten
* a6 - Overwritten
* a7 - Overwritten
*
*/
/* SBI debug console extension */
#define SBI_DBCN ( ( 'D' << 24 ) | ( 'B' << 16 ) | ( 'C' << 8 ) | 'N' )
#define SBI_DBCN_WRITE_BYTE 0x02
.macro print_char_dbcn
li a7, SBI_DBCN
li a6, SBI_DBCN_WRITE_BYTE
ecall
.endm
/*****************************************************************************
*
* Print character via legacy extension
*
*****************************************************************************
*
* Print a single character via the SBI putchar legacy extension.
*
* Parameters:
*
* a0 - Character to print
*
* Returns:
*
* a0 - Overwritten
* a7 - Overwritten
*
*/
/* SBI legacy console putchar */
#define SBI_LEGACY_PUTCHAR 0x01
.macro print_char_legacy
li a7, SBI_LEGACY_PUTCHAR
ecall
.endm
/*****************************************************************************
*
* Print message to debug console
@@ -76,13 +134,6 @@ prefix_virt:
*
*/
/* SBI debug console extension */
#define SBI_DBCN ( ( 'D' << 24 ) | ( 'B' << 16 ) | ( 'C' << 8 ) | 'N' )
#define SBI_DBCN_WRITE_BYTE 0x02
/* SBI legacy console putchar */
#define SBI_LEGACY_PUTCHAR 0x01
.section ".prefix.print_message", "ax", @progbits
.globl print_message
print_message:
@@ -108,13 +159,10 @@ print_message_alt:
lbu a0, (t1)
addi t1, t1, 1
beqz a0, 2f
li a7, SBI_DBCN
li a6, SBI_DBCN_WRITE_BYTE
ecall
print_char_dbcn
beqz a0, 1b
lbu a0, -1(t1)
li a7, SBI_LEGACY_PUTCHAR
ecall
print_char_legacy
j 1b
2:
/* Restore registers and return (via alternate link register) */
@@ -202,14 +250,11 @@ print_hex_value_alt:
1: /* Print each digit in turn */
srli a0, t1, ( __riscv_xlen - 4 )
nibble_to_ascii a0
li a7, SBI_DBCN
li a6, SBI_DBCN_WRITE_BYTE
ecall
print_char_dbcn
beqz a0, 2f
srli a0, t1, ( __riscv_xlen - 4 )
nibble_to_ascii a0
li a7, SBI_LEGACY_PUTCHAR
ecall
print_char_legacy
2: slli t1, t1, 4
addi t2, t2, -4
bgtz t2, 1b