u-boot/arch/x86/lib/tables.c
Bin Meng 07545d861c x86: Generate a valid MultiProcessor (MP) table
Implement write_mp_table() to create a minimal working MP table.
This includes an MP floating table, a configuration table header
and all of the 5 base configuration table entries. The I/O interrupt
assignment table entry is created based on the same information used
in the creation of PIRQ routing table from device tree. A check
duplicated entry logic is applied to prevent writing multiple I/O
interrupt entries with the same information.

Use a Kconfig option GENERATE_MP_TABLE to tell U-Boot whether we
need actually write the MP table at the F seg, just like we did for
PIRQ routing and SFI tables. With MP table existence, linux kernel
will switch to I/O APIC and local APIC to process all the peripheral
interrupts instead of 8259 PICs. This takes full advantage of the
multicore hardware and the SMP kernel.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Acked-by: Simon Glass <sjg@chromium.org>
2015-07-14 18:03:17 -06:00

54 lines
1.1 KiB
C

/*
* Copyright (C) 2015, Bin Meng <bmeng.cn@gmail.com>
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <asm/sfi.h>
#include <asm/mpspec.h>
#include <asm/tables.h>
u8 table_compute_checksum(void *v, int len)
{
u8 *bytes = v;
u8 checksum = 0;
int i;
for (i = 0; i < len; i++)
checksum -= bytes[i];
return checksum;
}
void table_fill_string(char *dest, const char *src, size_t n, char pad)
{
int start, len;
int i;
strncpy(dest, src, n);
/* Fill the remaining bytes with pad */
len = strlen(src);
start = len < n ? len : n;
for (i = start; i < n; i++)
dest[i] = pad;
}
void write_tables(void)
{
u32 __maybe_unused rom_table_end = ROM_TABLE_ADDR;
#ifdef CONFIG_GENERATE_PIRQ_TABLE
rom_table_end = write_pirq_routing_table(rom_table_end);
rom_table_end = ALIGN(rom_table_end, 1024);
#endif
#ifdef CONFIG_GENERATE_SFI_TABLE
rom_table_end = write_sfi_table(rom_table_end);
rom_table_end = ALIGN(rom_table_end, 1024);
#endif
#ifdef CONFIG_GENERATE_MP_TABLE
rom_table_end = write_mp_table(rom_table_end);
rom_table_end = ALIGN(rom_table_end, 1024);
#endif
}