linux/arch/blackfin/mach-bf561/secondary.S
Sonic Zhang c6345ab1a3 Blackfin: SMP: work around anomaly 05000491
In order to safely work around anomaly 05000491, we have to execute IFLUSH
from L1 instruction sram.  The trouble with multi-core systems is that all
L1 sram is visible only to the active core.  So we can't just place the
functions into L1 and call it directly.  We need to setup a jump table and
place the entry point in external memory.  This will call the right func
based on the active core.

In the process, convert from the manual relocation of a small bit of code
into Core B's L1 to the more general framework we already have in place
for loading arbitrary pieces of code into L1.

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2011-03-18 04:01:04 -04:00

228 lines
3.9 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)
/* 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;
trace_buffer_init(p0,r0);
/* Turn off the icache */
p0.l = LO(IMEM_CONTROL);
p0.h = HI(IMEM_CONTROL);
R1 = [p0];
R0 = ~ENICPLB;
R0 = R0 & R1;
/* Disabling of CPLBs should be proceeded by a CSYNC */
CSYNC;
[p0] = R0;
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;
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);
r7 = [p0 + PDA_DF_RETX];
p1.l = _init_saved_retx_coreb;
p1.h = _init_saved_retx_coreb;
[p1] = r7;
r7 = [p0 + PDA_DF_DCPLB];
p1.l = _init_saved_dcplb_fault_addr_coreb;
p1.h = _init_saved_dcplb_fault_addr_coreb;
[p1] = r7;
r7 = [p0 + PDA_DF_ICPLB];
p1.l = _init_saved_icplb_fault_addr_coreb;
p1.h = _init_saved_icplb_fault_addr_coreb;
[p1] = r7;
r7 = [p0 + PDA_DF_SEQSTAT];
p1.l = _init_saved_seqstat_coreb;
p1.h = _init_saved_seqstat_coreb;
[p1] = r7;
#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 */
p0.l = lo(EVT15);
p0.h = hi(EVT15);
p1.l = _coreb_start;
p1.h = _coreb_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 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)