linux/arch/blackfin/mach-bf561/secondary.S
Mike Frysinger b648072d3e Blackfin: SMP: optimize start up code a bit
This just imports all of the optimization work done in the
common startup code.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2011-07-23 01:10:42 -04:00

205 lines
4.0 KiB
ArmAsm

/*
* BF561 coreB bootstrap file
*
* Copyright 2007-2009 Analog Devices Inc.
* Philippe Gerum <rpm@xenomai.org>
*
* Licensed under the GPL-2 or later.
*/
#include <linux/linkage.h>
#include <linux/init.h>
#include <asm/blackfin.h>
#include <asm/asm-offsets.h>
#include <asm/trace.h>
/*
* This code must come first as CoreB is hardcoded (in hardware)
* to start at the beginning of its L1 instruction memory.
*/
.section .l1.text.head
/* Lay the initial stack into the L1 scratch area of Core B */
#define INITIAL_STACK (COREB_L1_SCRATCH_START + L1_SCRATCH_LENGTH - 12)
ENTRY(_coreb_trampoline_start)
/* 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;
/* 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);
/* Zero out registers required by Blackfin ABI */
/* 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;
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 */
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 */
p0.l = _init_retx_coreb;
p0.h = _init_retx_coreb;
R0 = RETX;
[P0] = R0;
#ifdef CONFIG_DEBUG_DOUBLEFAULT
/* Only save these if we are storing them,
* This happens here, since L1 gets clobbered
* below
*/
GET_PDA(p0, r0);
r5 = [p0 + PDA_DF_RETX];
p1.l = _init_saved_retx_coreb;
p1.h = _init_saved_retx_coreb;
[p1] = r5;
r5 = [p0 + PDA_DF_DCPLB];
p1.l = _init_saved_dcplb_fault_addr_coreb;
p1.h = _init_saved_dcplb_fault_addr_coreb;
[p1] = r5;
r5 = [p0 + PDA_DF_ICPLB];
p1.l = _init_saved_icplb_fault_addr_coreb;
p1.h = _init_saved_icplb_fault_addr_coreb;
[p1] = r5;
r5 = [p0 + PDA_DF_SEQSTAT];
p1.l = _init_saved_seqstat_coreb;
p1.h = _init_saved_seqstat_coreb;
[p1] = r5;
#endif
/* Initialize stack pointer */
sp.l = lo(INITIAL_STACK);
sp.h = hi(INITIAL_STACK);
fp = sp;
usp = sp;
/* This section keeps the processor in supervisor mode
* during core B startup. Branches to the idle task.
*/
/* EVT15 = _real_start */
p1.l = _coreb_start;
p1.h = _coreb_start;
[p5 + (EVT15 - COREMMR_BASE)] = p1;
csync;
r0 = EVT_IVG15 (z);
sti r0;
raise 15;
p0.l = .LWAIT_HERE;
p0.h = .LWAIT_HERE;
reti = p0;
#if defined(ANOMALY_05000281)
nop; nop; nop;
#endif
rti;
.LWAIT_HERE:
jump .LWAIT_HERE;
ENDPROC(_coreb_trampoline_start)
#ifdef CONFIG_HOTPLUG_CPU
.section ".text"
ENTRY(_coreb_die)
sp.l = lo(INITIAL_STACK);
sp.h = hi(INITIAL_STACK);
fp = sp;
usp = sp;
CLI R2;
SSYNC;
IDLE;
STI R2;
R0 = IWR_DISABLE_ALL;
P0.H = hi(SYSMMR_BASE);
P0.L = lo(SYSMMR_BASE);
[P0 + (SICB_IWR0 - SYSMMR_BASE)] = R0;
[P0 + (SICB_IWR1 - SYSMMR_BASE)] = R0;
SSYNC;
p0.h = hi(COREB_L1_CODE_START);
p0.l = lo(COREB_L1_CODE_START);
jump (p0);
ENDPROC(_coreb_die)
#endif
__INIT
ENTRY(_coreb_start)
[--sp] = reti;
p0.l = lo(WDOGB_CTL);
p0.h = hi(WDOGB_CTL);
r0 = 0xAD6(z);
w[p0] = r0; /* Clear the watchdog. */
ssync;
/*
* switch to IDLE stack.
*/
p0.l = _secondary_stack;
p0.h = _secondary_stack;
sp = [p0];
usp = sp;
fp = sp;
#ifdef CONFIG_HOTPLUG_CPU
p0.l = _hotplug_coreb;
p0.h = _hotplug_coreb;
r0 = [p0];
cc = BITTST(r0, 0);
if cc jump 3f;
#endif
sp += -12;
call _init_pda
sp += 12;
#ifdef CONFIG_HOTPLUG_CPU
3:
#endif
call _secondary_start_kernel;
.L_exit:
jump.s .L_exit;
ENDPROC(_coreb_start)