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+/*
+ * Common Blackfin startup code
+ *
+ * Copyright 2004-2008 Analog Devices Inc.
+ *
+ * Enter bugs at http://blackfin.uclinux.org/
+ *
+ * Licensed under the GPL-2 or later.
+ */
+
+#include <linux/linkage.h>
+#include <linux/init.h>
+#include <asm/blackfin.h>
+#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;
+
+ /* Save RETX, in case of doublefault */
+ p0.l = ___retx;
+ p0.h = ___retx;
+ R0 = RETX;
+ [P0] = R0;
+
+ /* 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
+
+ENTRY(_real_start)
+ /* Enable nested interrupts */
+ [--sp] = reti;
+
+ /* watchdog off for now */
+ p0.l = lo(WDOG_CTL);
+ p0.h = hi(WDOG_CTL);
+ r0 = 0xAD6(z);
+ w[p0] = r0;
+ ssync;
+
+ /* Zero out the bss region
+ * Note: this will fail if bss is 0 bytes ...
+ */
+ r0 = 0 (z);
+ r1.l = ___bss_start;
+ r1.h = ___bss_start;
+ r2.l = ___bss_stop;
+ r2.h = ___bss_stop;
+ r2 = r2 - r1;
+ r2 >>= 2;
+ p1 = r1;
+ p2 = r2;
+ lsetup (.L_clear_bss, .L_clear_bss) lc0 = p2;
+.L_clear_bss:
+ [p1++] = r0;
+
+ /* In case there is a NULL pointer reference,
+ * zero out region before stext
+ */
+ p1 = r0;
+ r2.l = __stext;
+ r2.h = __stext;
+ r2 >>= 2;
+ p2 = r2;
+ lsetup (.L_clear_zero, .L_clear_zero) lc0 = p2;
+.L_clear_zero:
+ [p1++] = r0;
+
+ /* Pass the u-boot arguments to the global value command line */
+ R0 = R7;
+ call _cmdline_init;
+
+ /* Load the current thread pointer and stack */
+ sp.l = _init_thread_union;
+ sp.h = _init_thread_union;
+ p1 = THREAD_SIZE (z);
+ sp = sp + p1;
+ usp = sp;
+ fp = sp;
+ jump.l _start_kernel;
+ENDPROC(_real_start)
+
+__FINIT
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