ARM: Defer lookup of machine_type to setup.c

Since the debug macros no longer depend on the machine type information,
the machine type lookup can be deferred to setup_arch() in setup.c which
simplifies the code somewhat.

We also move the __error_a functionality into setup.c for displaying a
message when a bad machine ID is passed to the kernel via the LL debug
code.  We also log this into the kernel ring buffer which makes it
possible to retrieve the message via a debugger.

Original idea from Grant Likely.

Acked-by: Grant Likely <grant.likely@secretlab.ca>
Tested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This commit is contained in:
Russell King 2011-01-12 17:50:42 +00:00
parent ebf53826e1
commit 6fc31d5444
4 changed files with 40 additions and 101 deletions

View File

@ -25,83 +25,6 @@
* machine ID for example).
*/
__HEAD
__error_a:
#ifdef CONFIG_DEBUG_LL
mov r4, r1 @ preserve machine ID
adr r0, str_a1
bl printascii
mov r0, r4
bl printhex8
adr r0, str_a2
bl printascii
adr r3, __lookup_machine_type_data
ldmia r3, {r4, r5, r6} @ get machine desc list
sub r4, r3, r4 @ get offset between virt&phys
add r5, r5, r4 @ convert virt addresses to
add r6, r6, r4 @ physical address space
1: ldr r0, [r5, #MACHINFO_TYPE] @ get machine type
bl printhex8
mov r0, #'\t'
bl printch
ldr r0, [r5, #MACHINFO_NAME] @ get machine name
add r0, r0, r4
bl printascii
mov r0, #'\n'
bl printch
add r5, r5, #SIZEOF_MACHINE_DESC @ next machine_desc
cmp r5, r6
blo 1b
adr r0, str_a3
bl printascii
b __error
ENDPROC(__error_a)
str_a1: .asciz "\nError: unrecognized/unsupported machine ID (r1 = 0x"
str_a2: .asciz ").\n\nAvailable machine support:\n\nID (hex)\tNAME\n"
str_a3: .asciz "\nPlease check your kernel config and/or bootloader.\n"
.align
#else
b __error
#endif
/*
* Lookup machine architecture in the linker-build list of architectures.
* Note that we can't use the absolute addresses for the __arch_info
* lists since we aren't running with the MMU on (and therefore, we are
* not in the correct address space). We have to calculate the offset.
*
* r1 = machine architecture number
* Returns:
* r3, r4, r6 corrupted
* r5 = mach_info pointer in physical address space
*/
__lookup_machine_type:
adr r3, __lookup_machine_type_data
ldmia r3, {r4, r5, r6}
sub r3, r3, r4 @ get offset between virt&phys
add r5, r5, r3 @ convert virt addresses to
add r6, r6, r3 @ physical address space
1: ldr r3, [r5, #MACHINFO_TYPE] @ get machine type
teq r3, r1 @ matches loader number?
beq 2f @ found
add r5, r5, #SIZEOF_MACHINE_DESC @ next machine_desc
cmp r5, r6
blo 1b
mov r5, #0 @ unknown machine
2: mov pc, lr
ENDPROC(__lookup_machine_type)
/*
* Look in arch/arm/kernel/arch.[ch] for information about the
* __arch_info structures.
*/
.align 2
.type __lookup_machine_type_data, %object
__lookup_machine_type_data:
.long .
.long __arch_info_begin
.long __arch_info_end
.size __lookup_machine_type_data, . - __lookup_machine_type_data
/* Determine validity of the r2 atags pointer. The heuristic requires
* that the pointer be aligned, in the first 16k of physical RAM and
@ -109,8 +32,6 @@ __lookup_machine_type_data:
* of this function may be more lenient with the physical address and
* may also be able to move the ATAGS block if necessary.
*
* r8 = machinfo
*
* Returns:
* r2 either valid atags pointer, or zero
* r5, r6 corrupted
@ -184,17 +105,6 @@ __mmap_switched_data:
.long init_thread_union + THREAD_START_SP @ sp
.size __mmap_switched_data, . - __mmap_switched_data
/*
* This provides a C-API version of __lookup_machine_type
*/
ENTRY(lookup_machine_type)
stmfd sp!, {r4 - r6, lr}
mov r1, r0
bl __lookup_machine_type
mov r0, r5
ldmfd sp!, {r4 - r6, pc}
ENDPROC(lookup_machine_type)
/*
* This provides a C-API version of __lookup_processor_type
*/

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@ -44,9 +44,6 @@ ENTRY(stext)
bl __lookup_processor_type @ r5=procinfo r9=cpuid
movs r10, r5 @ invalid processor (r5=0)?
beq __error_p @ yes, error 'p'
bl __lookup_machine_type @ r5=machinfo
movs r8, r5 @ invalid machine (r5=0)?
beq __error_a @ yes, error 'a'
adr lr, BSYM(__after_proc_init) @ return (PIC) address
ARM( add pc, r10, #PROCINFO_INITFUNC )

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@ -87,14 +87,10 @@ ENTRY(stext)
movs r10, r5 @ invalid processor (r5=0)?
THUMB( it eq ) @ force fixup-able long branch encoding
beq __error_p @ yes, error 'p'
bl __lookup_machine_type @ r5=machinfo
movs r8, r5 @ invalid machine (r5=0)?
THUMB( it eq ) @ force fixup-able long branch encoding
beq __error_a @ yes, error 'a'
/*
* r1 = machine no, r2 = atags,
* r8 = machinfo, r9 = cpuid, r10 = procinfo
* r9 = cpuid, r10 = procinfo
*/
bl __vet_atags
#ifdef CONFIG_SMP_ON_UP
@ -105,7 +101,7 @@ ENTRY(stext)
/*
* The following calls CPU specific code in a position independent
* manner. See arch/arm/mm/proc-*.S for details. r10 = base of
* xxx_proc_info structure selected by __lookup_machine_type
* xxx_proc_info structure selected by __lookup_processor_type
* above. On return, the CPU will be ready for the MMU to be
* turned on, and r0 will hold the CPU control register value.
*/
@ -124,7 +120,6 @@ ENDPROC(stext)
* amount which are required to get the kernel running, which
* generally means mapping in the kernel code.
*
* r8 = machinfo
* r9 = cpuid
* r10 = procinfo
*

View File

@ -308,7 +308,44 @@ static void __init cacheid_init(void)
* already provide the required functionality.
*/
extern struct proc_info_list *lookup_processor_type(unsigned int);
extern struct machine_desc *lookup_machine_type(unsigned int);
static void __init early_print(const char *str, ...)
{
extern void printascii(const char *);
char buf[256];
va_list ap;
va_start(ap, str);
vsnprintf(buf, sizeof(buf), str, ap);
va_end(ap);
#ifdef CONFIG_DEBUG_LL
printascii(buf);
#endif
printk("%s", buf);
}
static struct machine_desc * __init lookup_machine_type(unsigned int type)
{
extern struct machine_desc __arch_info_begin[], __arch_info_end[];
struct machine_desc *p;
for (p = __arch_info_begin; p < __arch_info_end; p++)
if (type == p->nr)
return p;
early_print("\n"
"Error: unrecognized/unsupported machine ID (r1 = 0x%08x).\n\n"
"Available machine support:\n\nID (hex)\tNAME\n", type);
for (p = __arch_info_begin; p < __arch_info_end; p++)
early_print("%08x\t%s\n", p->nr, p->name);
early_print("\nPlease check your kernel config and/or bootloader.\n");
while (true)
/* can't use cpu_relax() here as it may require MMU setup */;
}
static void __init feat_v6_fixup(void)
{