sparc32: Implement hard_smp_processor_id() via instruction patching.

This is the last non-trivial user of btfixup.

Like sparc64, use a special patch section to resolve the various
implementations of how to read the current CPU's ID when we don't
have current_thread_info()->cpu necessarily available.

Signed-off-by: David S. Miller <davem@davemloft.net>
Tested-by: Sam Ravnborg <sam@ravnborg.org>

10 files changed, 99 insertions, 175 deletions

diff --git a/arch/sparc/include/asm/smp_32.h b/arch/sparc/include/asm/smp_32.h
index 01c51c704341..f5b325e731dd 100644
--- a/arch/sparc/include/asm/smp_32.h
+++ b/arch/sparc/include/asm/smp_32.h
@@ -59,12 +59,9 @@ void smp_bogo(struct seq_file *);
 void smp_info(struct seq_file *);
 
 BTFIXUPDEF_CALL(void, smp_cross_call, smpfunc_t, cpumask_t, unsigned long, unsigned long, unsigned long, unsigned long)
-BTFIXUPDEF_CALL(int, __hard_smp_processor_id, void)
 BTFIXUPDEF_CALL(void, smp_ipi_resched, int);
 BTFIXUPDEF_CALL(void, smp_ipi_single, int);
 BTFIXUPDEF_CALL(void, smp_ipi_mask_one, int);
-BTFIXUPDEF_BLACKBOX(hard_smp_processor_id)
-BTFIXUPDEF_BLACKBOX(load_current)
 
 #define smp_cross_call(func,mask,arg1,arg2,arg3,arg4) BTFIXUP_CALL(smp_cross_call)(func,mask,arg1,arg2,arg3,arg4)
 
@@ -117,45 +114,7 @@ extern inline int hard_smpleon_processor_id(void)
         return cpuid;
 }
 
-#ifndef MODULE
-static inline int hard_smp_processor_id(void)
-{
-        int cpuid;
-
-        /* Black box - sun4m
-                __asm__ __volatile__("rd %%tbr, %0\n\t"
-                                     "srl %0, 12, %0\n\t"
-                                     "and %0, 3, %0\n\t" :
-                                     "=&r" (cpuid));
-                     - sun4d
-                __asm__ __volatile__("lda [%g0] ASI_M_VIKING_TMP1, %0\n\t"
-                                     "nop; nop" :
-                                     "=&r" (cpuid));
-                     - leon
-                __asm__ __volatile__(   "rd %asr17, %0\n\t"
-                                        "srl %0, 0x1c, %0\n\t"
-                                        "nop\n\t" :
-                                        "=&r" (cpuid));
-           See btfixup.h and btfixupprep.c to understand how a blackbox works.
-         */
-        __asm__ __volatile__("sethi %%hi(___b_hard_smp_processor_id), %0\n\t"
-                             "sethi %%hi(boot_cpu_id), %0\n\t"
-                             "ldub [%0 + %%lo(boot_cpu_id)], %0\n\t" :
-                             "=&r" (cpuid));
-        return cpuid;
-}
-#else
-static inline int hard_smp_processor_id(void)
-{
-        int cpuid;
-
-        __asm__ __volatile__("mov %%o7, %%g1\n\t"
-                             "call ___f___hard_smp_processor_id\n\t"
-                             " nop\n\t"
-                             "mov %%g2, %0\n\t" : "=r"(cpuid) : : "g1", "g2");
-        return cpuid;
-}
-#endif
+extern int hard_smp_processor_id(void);
 
 #define raw_smp_processor_id()          (current_thread_info()->cpu)
 
diff --git a/arch/sparc/include/asm/winmacro.h b/arch/sparc/include/asm/winmacro.h
index a9be04b0d049..9b7b21764cde 100644
--- a/arch/sparc/include/asm/winmacro.h
+++ b/arch/sparc/include/asm/winmacro.h
@@ -103,37 +103,24 @@
         st       %scratch, [%cur_reg + TI_W_SAVED];
 
 #ifdef CONFIG_SMP
-/* Results of LOAD_CURRENT() after BTFIXUP for SUN4M, SUN4D & LEON (comments) */
-#define LOAD_CURRENT4M(dest_reg, idreg) \
-        rd       %tbr, %idreg; \
-        sethi    %hi(current_set), %dest_reg; \
-        srl      %idreg, 10, %idreg; \
-        or       %dest_reg, %lo(current_set), %dest_reg; \
-        and      %idreg, 0xc, %idreg; \
-        ld       [%idreg + %dest_reg], %dest_reg;
-
-#define LOAD_CURRENT4D(dest_reg, idreg) \
-        lda      [%g0] ASI_M_VIKING_TMP1, %idreg; \
-        sethi   %hi(C_LABEL(current_set)), %dest_reg; \
-        sll     %idreg, 2, %idreg; \
-        or      %dest_reg, %lo(C_LABEL(current_set)), %dest_reg; \
-        ld      [%idreg + %dest_reg], %dest_reg;
-
-#define LOAD_CURRENT_LEON(dest_reg, idreg)                      \
-        rd      %asr17, %idreg;                                 \
-        sethi   %hi(current_set), %dest_reg;                    \
-        srl     %idreg, 0x1c, %idreg;                           \
-        or      %dest_reg, %lo(current_set), %dest_reg;         \
-        sll     %idreg, 0x2, %idreg;                            \
-        ld      [%idreg + %dest_reg], %dest_reg;
-
-/* Blackbox - take care with this... - check smp4m and smp4d before changing this. */
-#define LOAD_CURRENT(dest_reg, idreg)                                   \
-        sethi    %hi(___b_load_current), %idreg;                        \
-        sethi    %hi(current_set), %dest_reg;                   \
-        sethi    %hi(boot_cpu_id4), %idreg;                     \
-        or       %dest_reg, %lo(current_set), %dest_reg;        \
-        ldub     [%idreg + %lo(boot_cpu_id4)], %idreg;          \
+#define LOAD_CURRENT(dest_reg, idreg)                   \
+661:    rd      %tbr, %idreg;                           \
+        srl     %idreg, 10, %idreg;                     \
+        and     %idreg, 0xc, %idreg;                    \
+        .section        .cpuid_patch, "ax";             \
+        /* Instruction location. */                     \
+        .word           661b;                           \
+        /* SUN4D implementation. */                     \
+        lda      [%g0] ASI_M_VIKING_TMP1, %idreg;       \
+        sll      %idreg, 2, %idreg;                     \
+        nop;                                            \
+        /* LEON implementation. */                      \
+        rd      %asr17, %idreg;                         \
+        srl     %idreg, 0x1c, %idreg;                   \
+        sll     %idreg, 0x02, %idreg;                   \
+        .previous;                                      \
+        sethi    %hi(current_set), %dest_reg;           \
+        or       %dest_reg, %lo(current_set), %dest_reg;\
         ld       [%idreg + %dest_reg], %dest_reg;
 #else
 #define LOAD_CURRENT(dest_reg, idreg) \
diff --git a/arch/sparc/kernel/entry.S b/arch/sparc/kernel/entry.S
index d7143ba6a8ff..773f3f05bf26 100644
--- a/arch/sparc/kernel/entry.S
+++ b/arch/sparc/kernel/entry.S
@@ -7,6 +7,7 @@
  * Copyright (C) 1997 Anton Blanchard (anton@progsoc.uts.edu.au)
  */
 
+#include <linux/linkage.h>
 #include <linux/errno.h>
 
 #include <asm/head.h>
@@ -1347,4 +1348,26 @@ flushw_all:
         ret
          restore
 
+#ifdef CONFIG_SMP
+ENTRY(hard_smp_processor_id)
+661:    rd              %tbr, %g1
+        srl             %g1, 12, %o0
+        and             %o0, 3, %o0
+        .section        .cpuid_patch, "ax"
+        /* Instruction location. */
+        .word           661b
+        /* SUN4D implementation. */
+        lda             [%g0] ASI_M_VIKING_TMP1, %o0
+        nop
+        nop
+        /* LEON implementation. */
+        rd              %asr17, %o0
+        srl             %o0, 0x1c, %o0
+        nop
+        .previous
+        retl
+         nop
+ENDPROC(hard_smp_processor_id)
+#endif
+
 /* End of entry.S */
diff --git a/arch/sparc/kernel/kernel.h b/arch/sparc/kernel/kernel.h
index 8278df5d4ce7..1c1a7d39c7e1 100644
--- a/arch/sparc/kernel/kernel.h
+++ b/arch/sparc/kernel/kernel.h
@@ -80,8 +80,6 @@ extern unsigned int patchme_maybe_smp_msg[];
 extern void floppy_hardint(void);
 
 /* trampoline_32.S */
-extern int __smp4m_processor_id(void);
-extern int __smp4d_processor_id(void);
 extern unsigned long sun4m_cpu_startup;
 extern unsigned long sun4d_cpu_startup;
 
diff --git a/arch/sparc/kernel/leon_smp.c b/arch/sparc/kernel/leon_smp.c
index f3e3630e31a3..faff792d53c8 100644
--- a/arch/sparc/kernel/leon_smp.c
+++ b/arch/sparc/kernel/leon_smp.c
@@ -73,7 +73,7 @@ static inline unsigned long do_swap(volatile unsigned long *ptr,
 
 void __cpuinit leon_callin(void)
 {
-        int cpuid = hard_smpleon_processor_id();
+        int cpuid = hard_smp_processor_id();
 
         local_ops->cache_all();
         local_ops->tlb_all();
@@ -491,39 +491,12 @@ void leon_cross_call_irq(void)
         ccall_info.processors_out[i] = 1;
 }
 
-void __init leon_blackbox_id(unsigned *addr)
-{
-        int rd = *addr & 0x3e000000;
-        int rs1 = rd >> 11;
-
-        /* patch places where ___b_hard_smp_processor_id appears */
-        addr[0] = 0x81444000 | rd;      /* rd %asr17, reg */
-        addr[1] = 0x8130201c | rd | rs1;        /* srl reg, 0x1c, reg */
-        addr[2] = 0x01000000;   /* nop */
-}
-
-void __init leon_blackbox_current(unsigned *addr)
-{
-        int rd = *addr & 0x3e000000;
-        int rs1 = rd >> 11;
-
-        /* patch LOAD_CURRENT macro where ___b_load_current appears */
-        addr[0] = 0x81444000 | rd;      /* rd %asr17, reg */
-        addr[2] = 0x8130201c | rd | rs1;        /* srl reg, 0x1c, reg */
-        addr[4] = 0x81282002 | rd | rs1;        /* sll reg, 0x2, reg */
-
-}
-
 void __init leon_init_smp(void)
 {
         /* Patch ipi15 trap table */
         t_nmi[1] = t_nmi[1] + (linux_trap_ipi15_leon - linux_trap_ipi15_sun4m);
 
-        BTFIXUPSET_BLACKBOX(hard_smp_processor_id, leon_blackbox_id);
-        BTFIXUPSET_BLACKBOX(load_current, leon_blackbox_current);
         BTFIXUPSET_CALL(smp_cross_call, leon_cross_call, BTFIXUPCALL_NORM);
-        BTFIXUPSET_CALL(__hard_smp_processor_id, __leon_processor_id,
-                        BTFIXUPCALL_NORM);
         BTFIXUPSET_CALL(smp_ipi_resched, leon_ipi_resched, BTFIXUPCALL_NORM);
         BTFIXUPSET_CALL(smp_ipi_single, leon_ipi_single, BTFIXUPCALL_NORM);
         BTFIXUPSET_CALL(smp_ipi_mask_one, leon_ipi_mask_one, BTFIXUPCALL_NORM);
diff --git a/arch/sparc/kernel/setup_32.c b/arch/sparc/kernel/setup_32.c
index 6f294f371d68..2f7cfb5f7569 100644
--- a/arch/sparc/kernel/setup_32.c
+++ b/arch/sparc/kernel/setup_32.c
@@ -192,6 +192,52 @@ extern int root_mountflags;
 
 char reboot_command[COMMAND_LINE_SIZE];
 
+struct cpuid_patch_entry {
+        unsigned int    addr;
+        unsigned int    sun4d[3];
+        unsigned int    leon[3];
+};
+extern struct cpuid_patch_entry __cpuid_patch, __cpuid_patch_end;
+
+static void __init per_cpu_patch(void)
+{
+        struct cpuid_patch_entry *p;
+
+        if (sparc_cpu_model == sun4m) {
+                /* Nothing to do, this is what the unpatched code
+                 * targets.
+                 */
+                return;
+        }
+
+        p = &__cpuid_patch;
+        while (p < &__cpuid_patch_end) {
+                unsigned long addr = p->addr;
+                unsigned int *insns;
+
+                switch (sparc_cpu_model) {
+                case sun4d:
+                        insns = &p->sun4d[0];
+                        break;
+
+                case sparc_leon:
+                        insns = &p->leon[0];
+                        break;
+                default:
+                        prom_printf("Unknown cpu type, halting.\n");
+                        prom_halt();
+                }
+                *(unsigned int *) (addr + 0) = insns[0];
+                *(unsigned int *) (addr + 4) = insns[1];
+                *(unsigned int *) (addr + 8) = insns[2];
+        }
+#ifdef CONFIG_SMP
+        local_ops->cache_all();
+#else
+        sparc32_cachetlb_ops->cache_all();
+#endif
+}
+
 enum sparc_cpu sparc_cpu_model;
 EXPORT_SYMBOL(sparc_cpu_model);
 
@@ -295,6 +341,11 @@ void __init setup_arch(char **cmdline_p)
 
         paging_init();
 
+        /* Now that we have the cache ops hooked up, we can patch
+         * instructions.
+         */
+        per_cpu_patch();
+
         smp_setup_cpu_possible_map();
 }
 
diff --git a/arch/sparc/kernel/sparc_ksyms_32.c b/arch/sparc/kernel/sparc_ksyms_32.c
index 4ad7377e2d0f..e521c54560f9 100644
--- a/arch/sparc/kernel/sparc_ksyms_32.c
+++ b/arch/sparc/kernel/sparc_ksyms_32.c
@@ -28,10 +28,5 @@ EXPORT_SYMBOL(__ndelay);
 EXPORT_SYMBOL(__ret_efault);
 EXPORT_SYMBOL(empty_zero_page);
 
-/* Defined using magic */
-#ifdef CONFIG_SMP
-EXPORT_SYMBOL(BTFIXUP_CALL(__hard_smp_processor_id));
-#endif
-
 /* Exporting a symbol from /init/main.c */
 EXPORT_SYMBOL(saved_command_line);
diff --git a/arch/sparc/kernel/sun4d_smp.c b/arch/sparc/kernel/sun4d_smp.c
index f17fd287bf7d..38ca0aac2ef2 100644
--- a/arch/sparc/kernel/sun4d_smp.c
+++ b/arch/sparc/kernel/sun4d_smp.c
@@ -52,7 +52,7 @@ static inline void show_leds(int cpuid)
 
 void __cpuinit smp4d_callin(void)
 {
-        int cpuid = hard_smp4d_processor_id();
+        int cpuid = hard_smp_processor_id();
         unsigned long flags;
 
         /* Show we are alive */
@@ -354,7 +354,7 @@ static void smp4d_cross_call(smpfunc_t func, cpumask_t mask, unsigned long arg1,
 /* Running cross calls. */
 void smp4d_cross_call_irq(void)
 {
-        int i = hard_smp4d_processor_id();
+        int i = hard_smp_processor_id();
 
         ccall_info.processors_in[i] = 1;
         ccall_info.func(ccall_info.arg1, ccall_info.arg2, ccall_info.arg3,
@@ -365,7 +365,7 @@ void smp4d_cross_call_irq(void)
 void smp4d_percpu_timer_interrupt(struct pt_regs *regs)
 {
         struct pt_regs *old_regs;
-        int cpu = hard_smp4d_processor_id();
+        int cpu = hard_smp_processor_id();
         struct clock_event_device *ce;
         static int cpu_tick[NR_CPUS];
         static char led_mask[] = { 0xe, 0xd, 0xb, 0x7, 0xb, 0xd };
@@ -391,24 +391,6 @@ void smp4d_percpu_timer_interrupt(struct pt_regs *regs)
         set_irq_regs(old_regs);
 }
 
-void __init smp4d_blackbox_id(unsigned *addr)
-{
-        int rd = *addr & 0x3e000000;
-
-        addr[0] = 0xc0800800 | rd;              /* lda [%g0] ASI_M_VIKING_TMP1, reg */
-        addr[1] = 0x01000000;                   /* nop */
-        addr[2] = 0x01000000;                   /* nop */
-}
-
-void __init smp4d_blackbox_current(unsigned *addr)
-{
-        int rd = *addr & 0x3e000000;
-
-        addr[0] = 0xc0800800 | rd;              /* lda [%g0] ASI_M_VIKING_TMP1, reg */
-        addr[2] = 0x81282002 | rd | (rd >> 11); /* sll reg, 2, reg */
-        addr[4] = 0x01000000;                   /* nop */
-}
-
 void __init sun4d_init_smp(void)
 {
         int i;
@@ -417,10 +399,7 @@ void __init sun4d_init_smp(void)
         t_nmi[1] = t_nmi[1] + (linux_trap_ipi15_sun4d - linux_trap_ipi15_sun4m);
 
         /* And set btfixup... */
-        BTFIXUPSET_BLACKBOX(hard_smp_processor_id, smp4d_blackbox_id);
-        BTFIXUPSET_BLACKBOX(load_current, smp4d_blackbox_current);
         BTFIXUPSET_CALL(smp_cross_call, smp4d_cross_call, BTFIXUPCALL_NORM);
-        BTFIXUPSET_CALL(__hard_smp_processor_id, __smp4d_processor_id, BTFIXUPCALL_NORM);
         BTFIXUPSET_CALL(smp_ipi_resched, smp4d_ipi_resched, BTFIXUPCALL_NORM);
         BTFIXUPSET_CALL(smp_ipi_single, smp4d_ipi_single, BTFIXUPCALL_NORM);
         BTFIXUPSET_CALL(smp_ipi_mask_one, smp4d_ipi_mask_one, BTFIXUPCALL_NORM);
diff --git a/arch/sparc/kernel/sun4m_smp.c b/arch/sparc/kernel/sun4m_smp.c
index afcf6743f0eb..ff74d33e2709 100644
--- a/arch/sparc/kernel/sun4m_smp.c
+++ b/arch/sparc/kernel/sun4m_smp.c
@@ -281,32 +281,9 @@ void smp4m_percpu_timer_interrupt(struct pt_regs *regs)
         set_irq_regs(old_regs);
 }
 
-static void __init smp4m_blackbox_id(unsigned *addr)
-{
-        int rd = *addr & 0x3e000000;
-        int rs1 = rd >> 11;
-
-        addr[0] = 0x81580000 | rd;              /* rd %tbr, reg */
-        addr[1] = 0x8130200c | rd | rs1;        /* srl reg, 0xc, reg */
-        addr[2] = 0x80082003 | rd | rs1;        /* and reg, 3, reg */
-}
-
-static void __init smp4m_blackbox_current(unsigned *addr)
-{
-        int rd = *addr & 0x3e000000;
-        int rs1 = rd >> 11;
-
-        addr[0] = 0x81580000 | rd;              /* rd %tbr, reg */
-        addr[2] = 0x8130200a | rd | rs1;        /* srl reg, 0xa, reg */
-        addr[4] = 0x8008200c | rd | rs1;        /* and reg, 0xc, reg */
-}
-
 void __init sun4m_init_smp(void)
 {
-        BTFIXUPSET_BLACKBOX(hard_smp_processor_id, smp4m_blackbox_id);
-        BTFIXUPSET_BLACKBOX(load_current, smp4m_blackbox_current);
         BTFIXUPSET_CALL(smp_cross_call, smp4m_cross_call, BTFIXUPCALL_NORM);
-        BTFIXUPSET_CALL(__hard_smp_processor_id, __smp4m_processor_id, BTFIXUPCALL_NORM);
         BTFIXUPSET_CALL(smp_ipi_resched, smp4m_ipi_resched, BTFIXUPCALL_NORM);
         BTFIXUPSET_CALL(smp_ipi_single, smp4m_ipi_single, BTFIXUPCALL_NORM);
         BTFIXUPSET_CALL(smp_ipi_mask_one, smp4m_ipi_mask_one, BTFIXUPCALL_NORM);
diff --git a/arch/sparc/kernel/trampoline_32.S b/arch/sparc/kernel/trampoline_32.S
index 691f484e03b3..7364ddc9e5aa 100644
--- a/arch/sparc/kernel/trampoline_32.S
+++ b/arch/sparc/kernel/trampoline_32.S
@@ -15,8 +15,8 @@
 #include <asm/contregs.h>
 #include <asm/thread_info.h>
 
-        .globl sun4m_cpu_startup, __smp4m_processor_id, __leon_processor_id
-        .globl sun4d_cpu_startup, __smp4d_processor_id
+        .globl sun4m_cpu_startup
+        .globl sun4d_cpu_startup
 
         __CPUINIT
         .align 4
@@ -94,24 +94,6 @@ smp_do_cpu_idle:
         call    cpu_panic
          nop
 
-__smp4m_processor_id:
-        rd      %tbr, %g2
-        srl     %g2, 12, %g2
-        and     %g2, 3, %g2
-        retl
-         mov    %g1, %o7
-
-__smp4d_processor_id:
-        lda     [%g0] ASI_M_VIKING_TMP1, %g2
-        retl
-         mov    %g1, %o7
-
-__leon_processor_id:
-        rd     %asr17,%g2
-        srl    %g2,28,%g2
-        retl
-         mov    %g1, %o7
-
 /* CPUID in bootbus can be found at PA 0xff0140000 */
 #define SUN4D_BOOTBUS_CPUID     0xf0140000