Blackfin: SMP: optimize start up code a bit
Mike Frysinger [Sun, 29 May 2011 20:05:03 +0000 (16:05 -0400)]
This just imports all of the optimization work done in the
common startup code.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>

arch/blackfin/mach-bf561/secondary.S

index 4c46283..348c919 100644 (file)
 #define INITIAL_STACK  (COREB_L1_SCRATCH_START + L1_SCRATCH_LENGTH - 12)
 
 ENTRY(_coreb_trampoline_start)
-       /* Set the SYSCFG register */
-       R0 = 0x36;
-       SYSCFG = R0; /*Enable Cycle Counter and Nesting Of Interrupts(3rd Bit)*/
-       R0 = 0;
-
-       /*Clear Out All the data and pointer  Registers*/
-       R1 = R0;
-       R2 = R0;
-       R3 = R0;
-       R4 = R0;
-       R5 = R0;
-       R6 = R0;
-       R7 = R0;
-
-       P0 = R0;
-       P1 = R0;
-       P2 = R0;
-       P3 = R0;
-       P4 = R0;
-       P5 = R0;
-
-       LC0 = r0;
-       LC1 = r0;
-       L0 = r0;
-       L1 = r0;
-       L2 = r0;
-       L3 = r0;
-
-       /* Clear Out All the DAG Registers*/
-       B0 = r0;
-       B1 = r0;
-       B2 = r0;
-       B3 = r0;
-
-       I0 = r0;
-       I1 = r0;
-       I2 = r0;
-       I3 = r0;
-
-       M0 = r0;
-       M1 = r0;
-       M2 = r0;
-       M3 = r0;
+       /* Enable Cycle Counter and Nesting Of Interrupts */
+#ifdef CONFIG_BFIN_SCRATCH_REG_CYCLES
+       R0 = SYSCFG_SNEN;
+#else
+       R0 = SYSCFG_SNEN | SYSCFG_CCEN;
+#endif
+       SYSCFG = R0;
 
-       trace_buffer_init(p0,r0);
+       /* Optimization register tricks: keep a base value in the
+        * reserved P registers so we use the load/store with an
+        * offset syntax.  R0 = [P5 + <constant>];
+        *   P5 - core MMR base
+        *   R6 - 0
+        */
+       r6 = 0;
+       p5.l = 0;
+       p5.h = hi(COREMMR_BASE);
 
-       /* Turn off the icache */
-       p0.l = LO(IMEM_CONTROL);
-       p0.h = HI(IMEM_CONTROL);
-       R1 = [p0];
-       R0 = ~ENICPLB;
-       R0 = R0 & R1;
+       /* Zero out registers required by Blackfin ABI */
 
-       /* Disabling of CPLBs should be proceeded by a CSYNC */
+       /* Disable circular buffers */
+       L0 = r6;
+       L1 = r6;
+       L2 = r6;
+       L3 = r6;
+
+       /* Disable hardware loops in case we were started by 'go' */
+       LC0 = r6;
+       LC1 = r6;
+
+       /*
+        * Clear ITEST_COMMAND and DTEST_COMMAND registers,
+        * Leaving these as non-zero can confuse the emulator
+        */
+       [p5 + (DTEST_COMMAND - COREMMR_BASE)] = r6;
+       [p5 + (ITEST_COMMAND - COREMMR_BASE)] = r6;
        CSYNC;
-       [p0] = R0;
+
+       trace_buffer_init(p0,r0);
+
+       /* Turn off the icache */
+       r1 = [p5 + (IMEM_CONTROL - COREMMR_BASE)];
+       BITCLR (r1, ENICPLB_P);
+       [p5 + (IMEM_CONTROL - COREMMR_BASE)] = r1;
        SSYNC;
 
        /* Turn off the dcache */
-       p0.l = LO(DMEM_CONTROL);
-       p0.h = HI(DMEM_CONTROL);
-       R1 = [p0];
-       R0 = ~ENDCPLB;
-       R0 = R0 & R1;
-
-       /* Disabling of CPLBs should be proceeded by a CSYNC */
-       CSYNC;
-       [p0] = R0;
+       r1 = [p5 + (DMEM_CONTROL - COREMMR_BASE)];
+       BITCLR (r1, ENDCPLB_P);
+       [p5 + (DMEM_CONTROL - COREMMR_BASE)] = r1;
        SSYNC;
 
        /* in case of double faults, save a few things */
@@ -105,25 +87,25 @@ ENTRY(_coreb_trampoline_start)
         * below
         */
        GET_PDA(p0, r0);
-       r7 = [p0 + PDA_DF_RETX];
+       r5 = [p0 + PDA_DF_RETX];
        p1.l = _init_saved_retx_coreb;
        p1.h = _init_saved_retx_coreb;
-       [p1] = r7;
+       [p1] = r5;
 
-       r7 = [p0 + PDA_DF_DCPLB];
+       r5 = [p0 + PDA_DF_DCPLB];
        p1.l = _init_saved_dcplb_fault_addr_coreb;
        p1.h = _init_saved_dcplb_fault_addr_coreb;
-       [p1] = r7;
+       [p1] = r5;
 
-       r7 = [p0 + PDA_DF_ICPLB];
+       r5 = [p0 + PDA_DF_ICPLB];
        p1.l = _init_saved_icplb_fault_addr_coreb;
        p1.h = _init_saved_icplb_fault_addr_coreb;
-       [p1] = r7;
+       [p1] = r5;
 
-       r7 = [p0 + PDA_DF_SEQSTAT];
+       r5 = [p0 + PDA_DF_SEQSTAT];
        p1.l = _init_saved_seqstat_coreb;
        p1.h = _init_saved_seqstat_coreb;
-       [p1] = r7;
+       [p1] = r5;
 #endif
 
        /* Initialize stack pointer */
@@ -138,19 +120,13 @@ ENTRY(_coreb_trampoline_start)
 
        /* EVT15 = _real_start */
 
-       p0.l = lo(EVT15);
-       p0.h = hi(EVT15);
        p1.l = _coreb_start;
        p1.h = _coreb_start;
-       [p0] = p1;
+       [p5 + (EVT15 - COREMMR_BASE)] = p1;
        csync;
 
-       p0.l = lo(IMASK);
-       p0.h = hi(IMASK);
-       p1.l = IMASK_IVG15;
-       p1.h = 0x0;
-       [p0] = p1;
-       csync;
+       r0 = EVT_IVG15 (z);
+       sti r0;
 
        raise 15;
        p0.l = .LWAIT_HERE;