| Message ID | 1392149085-14366-3-git-send-email-julien.grall@linaro.org |
|---|---|
| State | RFC |
| Headers | show |
On Tue, 2014-02-11 at 20:04 +0000, Julien Grall wrote: > Looking for a specific proc_info structure is already implemented in assembly. > Implement lookup_processor_type to avoid duplicate code between C and > assembly. > > This function searches the proc_info_list structure following the processor > ID. If the search fail, it will return NULL, otherwise a pointer to this > structure for the specific processor. > > Signed-off-by: Julien Grall <julien.grall@linaro.org> Acked-by: Ian Campbell <ian.campbell@citrix.com> > --- > xen/arch/arm/arm32/head.S | 57 ++++++++++++++++++++++++++++++++++----------- > 1 file changed, 43 insertions(+), 14 deletions(-) > > diff --git a/xen/arch/arm/arm32/head.S b/xen/arch/arm/arm32/head.S > index 77f5518..68fb499 100644 > --- a/xen/arch/arm/arm32/head.S > +++ b/xen/arch/arm/arm32/head.S > @@ -198,26 +198,16 @@ skip_bss: > PRINT("- Setting up control registers -\r\n") > > /* Get processor specific proc info into r1 */ > - mrc CP32(r0, MIDR) /* r0 := our cpu id */ > - ldr r1, = __proc_info_start > - add r1, r1, r10 /* r1 := paddr of table (start) */ > - ldr r2, = __proc_info_end > - add r2, r2, r10 /* r2 := paddr of table (end) */ > -1: ldr r3, [r1, #PROCINFO_cpu_mask] > - and r4, r0, r3 /* r4 := our cpu id with mask */ > - ldr r3, [r1, #PROCINFO_cpu_val] /* r3 := cpu val in current proc info */ > - teq r4, r3 > - beq 2f /* Match => exit, or try next proc info */ > - add r1, r1, #PROCINFO_sizeof > - cmp r1, r2 > - blo 1b > + bl __lookup_processor_type > + teq r1, #0 > + bne 1f > mov r4, r0 > PRINT("- Missing processor info: ") > mov r0, r4 > bl putn > PRINT(" -\r\n") > b fail > -2: > +1: > > /* Jump to cpu_init */ > ldr r1, [r1, #PROCINFO_cpu_init] /* r1 := vaddr(init func) */ > @@ -545,6 +535,45 @@ putn: mov pc, lr > > #endif /* !CONFIG_EARLY_PRINTK */ > > +/* This provides a C-API version of __lookup_processor_type */ > +GLOBAL(lookup_processor_type) > + stmfd sp!, {r4, r10, lr} > + mov r10, #0 /* r10 := offset between virt&phys */ > + bl __lookup_processor_type > + mov r0, r1 > + ldmfd sp!, {r4, r10, pc} > + > +/* Read processor ID register (CP#15, CR0), and Look up in the linker-built > + * supported processor list. Note that we can't use the absolute addresses for > + * the __proc_info lists since we aren't running with the MMU on (and therefore, > + * we are not in correct address space). We have to calculate the offset. > + * > + * r10: offset between virt&phys > + * > + * Returns: > + * r0: CPUID > + * r1: proc_info pointer > + * Clobbers r2-r4 > + */ > +__lookup_processor_type: > + mrc CP32(r0, MIDR) /* r0 := our cpu id */ > + ldr r1, = __proc_info_start > + add r1, r1, r10 /* r1 := paddr of table (start) */ > + ldr r2, = __proc_info_end > + add r2, r2, r10 /* r2 := paddr of table (end) */ > +1: ldr r3, [r1, #PROCINFO_cpu_mask] > + and r4, r0, r3 /* r4 := our cpu id with mask */ > + ldr r3, [r1, #PROCINFO_cpu_val] /* r3 := cpu val in current proc info */ > + teq r4, r3 > + beq 2f /* Match => exit, or try next proc info */ > + add r1, r1, #PROCINFO_sizeof > + cmp r1, r2 > + blo 1b > + /* We failed to find the proc_info, return NULL */ > + mov r1, #0 > +2: > + mov pc, lr > + > /* > * Local variables: > * mode: ASM
diff --git a/xen/arch/arm/arm32/head.S b/xen/arch/arm/arm32/head.S index 77f5518..68fb499 100644 --- a/xen/arch/arm/arm32/head.S +++ b/xen/arch/arm/arm32/head.S @@ -198,26 +198,16 @@ skip_bss: PRINT("- Setting up control registers -\r\n") /* Get processor specific proc info into r1 */ - mrc CP32(r0, MIDR) /* r0 := our cpu id */ - ldr r1, = __proc_info_start - add r1, r1, r10 /* r1 := paddr of table (start) */ - ldr r2, = __proc_info_end - add r2, r2, r10 /* r2 := paddr of table (end) */ -1: ldr r3, [r1, #PROCINFO_cpu_mask] - and r4, r0, r3 /* r4 := our cpu id with mask */ - ldr r3, [r1, #PROCINFO_cpu_val] /* r3 := cpu val in current proc info */ - teq r4, r3 - beq 2f /* Match => exit, or try next proc info */ - add r1, r1, #PROCINFO_sizeof - cmp r1, r2 - blo 1b + bl __lookup_processor_type + teq r1, #0 + bne 1f mov r4, r0 PRINT("- Missing processor info: ") mov r0, r4 bl putn PRINT(" -\r\n") b fail -2: +1: /* Jump to cpu_init */ ldr r1, [r1, #PROCINFO_cpu_init] /* r1 := vaddr(init func) */ @@ -545,6 +535,45 @@ putn: mov pc, lr #endif /* !CONFIG_EARLY_PRINTK */ +/* This provides a C-API version of __lookup_processor_type */ +GLOBAL(lookup_processor_type) + stmfd sp!, {r4, r10, lr} + mov r10, #0 /* r10 := offset between virt&phys */ + bl __lookup_processor_type + mov r0, r1 + ldmfd sp!, {r4, r10, pc} + +/* Read processor ID register (CP#15, CR0), and Look up in the linker-built + * supported processor list. Note that we can't use the absolute addresses for + * the __proc_info lists since we aren't running with the MMU on (and therefore, + * we are not in correct address space). We have to calculate the offset. + * + * r10: offset between virt&phys + * + * Returns: + * r0: CPUID + * r1: proc_info pointer + * Clobbers r2-r4 + */ +__lookup_processor_type: + mrc CP32(r0, MIDR) /* r0 := our cpu id */ + ldr r1, = __proc_info_start + add r1, r1, r10 /* r1 := paddr of table (start) */ + ldr r2, = __proc_info_end + add r2, r2, r10 /* r2 := paddr of table (end) */ +1: ldr r3, [r1, #PROCINFO_cpu_mask] + and r4, r0, r3 /* r4 := our cpu id with mask */ + ldr r3, [r1, #PROCINFO_cpu_val] /* r3 := cpu val in current proc info */ + teq r4, r3 + beq 2f /* Match => exit, or try next proc info */ + add r1, r1, #PROCINFO_sizeof + cmp r1, r2 + blo 1b + /* We failed to find the proc_info, return NULL */ + mov r1, #0 +2: + mov pc, lr + /* * Local variables: * mode: ASM
Looking for a specific proc_info structure is already implemented in assembly. Implement lookup_processor_type to avoid duplicate code between C and assembly. This function searches the proc_info_list structure following the processor ID. If the search fail, it will return NULL, otherwise a pointer to this structure for the specific processor. Signed-off-by: Julien Grall <julien.grall@linaro.org> --- xen/arch/arm/arm32/head.S | 57 ++++++++++++++++++++++++++++++++++----------- 1 file changed, 43 insertions(+), 14 deletions(-)