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-rw-r--r--arch/blackfin/mach-common/head.S131
1 files changed, 129 insertions, 2 deletions
diff --git a/arch/blackfin/mach-common/head.S b/arch/blackfin/mach-common/head.S
index 6a989a031ed..2c69ad49894 100644
--- a/arch/blackfin/mach-common/head.S
+++ b/arch/blackfin/mach-common/head.S
@@ -14,13 +14,140 @@
#include <asm/thread_info.h>
#include <asm/trace.h>
+__INIT
+
+#define INITIAL_STACK (L1_SCRATCH_START + L1_SCRATCH_LENGTH - 12)
+
+ENTRY(__start)
+ /* R0: argument of command line string, passed from uboot, save it */
+ R7 = 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;
+ R0 = 0;
+
+ /* Clear Out All the data and pointer Registers */
+ R1 = R0;
+ R2 = R0;
+ R3 = R0;
+ R4 = R0;
+ R5 = R0;
+ R6 = 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;
+
+ trace_buffer_init(p0,r0);
+ P0 = R1;
+ R0 = R1;
+
+ /* Turn off the icache */
+ p0.l = LO(IMEM_CONTROL);
+ p0.h = HI(IMEM_CONTROL);
+ R1 = [p0];
+ R0 = ~ENICPLB;
+ R0 = R0 & R1;
+ [p0] = R0;
+ SSYNC;
+
+ /* Turn off the dcache */
+ p0.l = LO(DMEM_CONTROL);
+ p0.h = HI(DMEM_CONTROL);
+ R1 = [p0];
+ R0 = ~ENDCPLB;
+ R0 = R0 & R1;
+ [p0] = R0;
+ SSYNC;
+
+ /* Let each Blackfin family do its own thing */
+ call _mach_early_start;
+
+ /* Initialize stack pointer */
+ sp.l = lo(INITIAL_STACK);
+ sp.h = hi(INITIAL_STACK);
+ fp = sp;
+ usp = sp;
+
+#ifdef CONFIG_EARLY_PRINTK
+ call _init_early_exception_vectors;
+#endif
+
+ /* Put The Code for PLL Programming and SDRAM Programming in L1 ISRAM */
+ call _bf53x_relocate_l1_mem;
+#ifdef CONFIG_BFIN_KERNEL_CLOCK
+ call _start_dma_code;
+#endif
+
+ /* This section keeps the processor in supervisor mode
+ * during kernel boot. Switches to user mode at end of boot.
+ * See page 3-9 of Hardware Reference manual for documentation.
+ */
+
+ /* EVT15 = _real_start */
+
+ p0.l = lo(EVT15);
+ p0.h = hi(EVT15);
+ p1.l = _real_start;
+ p1.h = _real_start;
+ [p0] = p1;
+ csync;
+
+ p0.l = lo(IMASK);
+ p0.h = hi(IMASK);
+ p1.l = IMASK_IVG15;
+ p1.h = 0x0;
+ [p0] = p1;
+ csync;
+
+ raise 15;
+ p0.l = .LWAIT_HERE;
+ p0.h = .LWAIT_HERE;
+ reti = p0;
+#if ANOMALY_05000281
+ nop; nop; nop;
+#endif
+ rti;
+
+.LWAIT_HERE:
+ jump .LWAIT_HERE;
+ENDPROC(__start)
+
/* A little BF561 glue ... */
#ifndef WDOG_CTL
# define WDOG_CTL WDOGA_CTL
#endif
-__INIT
-
ENTRY(_real_start)
/* Enable nested interrupts */
[--sp] = reti;