x86, boot: add linked list of struct setup_data
This patch adds a field of 64-bit physical pointer to NULL terminated
single linked list of struct setup_data to real-mode kernel
header. This is used as a more extensible boot parameters passing
mechanism.
Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/arch/x86/boot/header.S b/arch/x86/boot/header.S
index 6d2df8d..af86e43 100644
--- a/arch/x86/boot/header.S
+++ b/arch/x86/boot/header.S
@@ -120,7 +120,7 @@
# Part 2 of the header, from the old setup.S
.ascii "HdrS" # header signature
- .word 0x0208 # header version number (>= 0x0105)
+ .word 0x0209 # header version number (>= 0x0105)
# or else old loadlin-1.5 will fail)
.globl realmode_swtch
realmode_swtch: .word 0, 0 # default_switch, SETUPSEG
@@ -227,6 +227,10 @@
payload_offset: .long input_data
payload_length: .long input_data_end-input_data
+setup_data: .quad 0 # 64-bit physical pointer to
+ # single linked list of
+ # struct setup_data
+
# End of setup header #####################################################
.section ".inittext", "ax"
diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c
index d31d6b7..e25c57b 100644
--- a/arch/x86/kernel/head64.c
+++ b/arch/x86/kernel/head64.c
@@ -11,6 +11,7 @@
#include <linux/string.h>
#include <linux/percpu.h>
#include <linux/start_kernel.h>
+#include <linux/io.h>
#include <asm/processor.h>
#include <asm/proto.h>
@@ -100,6 +101,24 @@
reserve_early(lowmem, 0x100000, "BIOS reserved");
}
+static void __init reserve_setup_data(void)
+{
+ struct setup_data *data;
+ unsigned long pa_data;
+ char buf[32];
+
+ if (boot_params.hdr.version < 0x0209)
+ return;
+ pa_data = boot_params.hdr.setup_data;
+ while (pa_data) {
+ data = early_ioremap(pa_data, sizeof(*data));
+ sprintf(buf, "setup data %x", data->type);
+ reserve_early(pa_data, pa_data+sizeof(*data)+data->len, buf);
+ pa_data = data->next;
+ early_iounmap(data, sizeof(*data));
+ }
+}
+
void __init x86_64_start_kernel(char * real_mode_data)
{
int i;
@@ -156,6 +175,7 @@
#endif
reserve_ebda_region();
+ reserve_setup_data();
/*
* At this point everything still needed from the boot loader
diff --git a/arch/x86/kernel/setup_64.c b/arch/x86/kernel/setup_64.c
index 17bdf23..e1a21d6 100644
--- a/arch/x86/kernel/setup_64.c
+++ b/arch/x86/kernel/setup_64.c
@@ -264,6 +264,26 @@
machine_specific_memory_setup();
}
+static void __init parse_setup_data(void)
+{
+ struct setup_data *data;
+ unsigned long pa_data;
+
+ if (boot_params.hdr.version < 0x0209)
+ return;
+ pa_data = boot_params.hdr.setup_data;
+ while (pa_data) {
+ data = early_ioremap(pa_data, PAGE_SIZE);
+ switch (data->type) {
+ default:
+ break;
+ }
+ free_early(pa_data, pa_data+sizeof(*data)+data->len);
+ pa_data = data->next;
+ early_iounmap(data, PAGE_SIZE);
+ }
+}
+
/*
* setup_arch - architecture-specific boot-time initializations
*
@@ -316,6 +336,8 @@
strlcpy(command_line, boot_command_line, COMMAND_LINE_SIZE);
*cmdline_p = command_line;
+ parse_setup_data();
+
parse_early_param();
#ifdef CONFIG_PROVIDE_OHCI1394_DMA_INIT
diff --git a/include/asm-x86/bootparam.h b/include/asm-x86/bootparam.h
index 5115135..e865990 100644
--- a/include/asm-x86/bootparam.h
+++ b/include/asm-x86/bootparam.h
@@ -9,6 +9,17 @@
#include <asm/ist.h>
#include <video/edid.h>
+/* setup data types */
+#define SETUP_NONE 0
+
+/* extensible setup data list node */
+struct setup_data {
+ u64 next;
+ u32 type;
+ u32 len;
+ u8 data[0];
+};
+
struct setup_header {
__u8 setup_sects;
__u16 root_flags;
@@ -46,6 +57,9 @@
__u32 cmdline_size;
__u32 hardware_subarch;
__u64 hardware_subarch_data;
+ __u32 payload_offset;
+ __u32 payload_length;
+ __u64 setup_data;
} __attribute__((packed));
struct sys_desc_table {