/*
* OMAP44xx sleep code.
*
* Copyright (C) 2011 Texas Instruments, Inc.
* Santosh Shilimkar <santosh.shilimkar@ti.com>
*
* This program is free software,you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/linkage.h>
#include <asm/smp_scu.h>
#include <asm/memory.h>
#include <asm/hardware/cache-l2x0.h>
#include <plat/omap44xx.h>
#include <mach/omap-secure.h>
#include "common.h"
#include "omap4-sar-layout.h"
#if defined(CONFIG_SMP) && defined(CONFIG_PM)
.macro DO_SMC
dsb
smc #0
dsb
.endm
ppa_zero_params:
.word 0x0
ppa_por_params:
.word 1, 0
/*
* =============================
* == CPU suspend finisher ==
* =============================
*
* void omap4_finish_suspend(unsigned long cpu_state)
*
* This function code saves the CPU context and performs the CPU
* power down sequence. Calling WFI effectively changes the CPU
* power domains states to the desired target power state.
*
* @cpu_state : contains context save state (r0)
* 0 - No context lost
* 1 - CPUx L1 and logic lost: MPUSS CSWR
* 2 - CPUx L1 and logic lost + GIC lost: MPUSS OSWR
* 3 - CPUx L1 and logic lost + GIC + L2 lost: MPUSS OFF
* @return: This function never returns for CPU OFF and DORMANT power states.
* Post WFI, CPU transitions to DORMANT or OFF power state and on wake-up
* from this follows a full CPU reset path via ROM code to CPU restore code.
* The restore function pointer is stored at CPUx_WAKEUP_NS_PA_ADDR_OFFSET.
* It returns to the caller for CPU INACTIVE and ON power states or in case
* CPU failed to transition to targeted OFF/DORMANT state.
*
* omap4_finish_suspend() calls v7_flush_dcache_all() which doesn't save
* stack frame and it expects the caller to take care of it. Hence the entire
* stack frame is saved to avoid possible stack corruption.
*/
ENTRY(omap4_finish_suspend)
stmfd sp!, {r4-r12, lr}
cmp r0, #0x0
beq do_WFI @ No lowpower state, jump to WFI
/*
* Flush all data from the L1 data cache before disabling
* SCTLR.C bit.
*/
bl omap4_get_sar_ram_base
ldr r9, [r0, #OMAP_TYPE_OFFSET]
cmp r9, #0x1 @ Check for HS device
bne skip_secure_l1_clean
mov r0, #SCU_PM_NORMAL
mov r1, #0xFF @ clean seucre L1
stmfd r13!, {r4-r12, r14}
ldr r12, =OMAP4_MON_SCU_PWR_INDEX
DO_SMC
ldmfd r13!, {r4-r12, r14}
skip_secure_l1_clean:
bl v7_flush_dcache_all
/*
* Clear the SCTLR.C bit to prevent further data cache
* allocation. Clearing SCTLR.C would make all the data accesses
* strongly ordered and would not hit the cache.
*/
mrc p15, 0, r0, c1, c0, 0
bic r0, r0, #(1 << 2) @ Disable the C bit
mcr p15, 0, r0, c1, c0, 0
isb
/*
* Invalidate L1 data cache. Even though only invalidate is
* necessary exported flush API is used here. Doing clean
* on already clean cache would be almost NOP.
*/
bl v7_flush_dcache_all
/*
* Switch the CPU from Symmetric Multiprocessing (SMP) mode
* to AsymmetricMultiprocessing (AMP) mode by programming
* the SCU power status to DORMANT or OFF mode.
* This enables the CPU to be taken out of coherency by
* preventing the CPU from receiving cache, TLB, or BTB
* maintenance operations broadcast by other CPUs in the cluster.
*/
bl omap4_get_sar_ram_base
mov r8, r0
ldr r9, [r8, #OMAP_TYPE_OFFSET]
cmp r9, #0x1 @ Check for HS device
bne scu_gp_set
mrc p15, 0, r0, c0, c0, 5 @ Read MPIDR
ands r0, r0, #0x0f
ldreq r0, [r8, #SCU_OFFSET0]
ldrne r0, [r8, #SCU_OFFSET1]
mov r1, #0x00
stmfd r13!, {r4-r12, r14}
ldr r12, =OMAP4_MON_SCU_PWR_INDEX
DO_SMC
ldmfd r13!, {r4-r12, r14}
b skip_scu_gp_set
scu_gp_set:
mrc p15, 0, r0, c0, c0, 5 @ Read MPIDR
ands r0, r0, #0x0f
ldreq r1, [r8, #SCU_OFFSET0]
ldrne r1, [r8, #SCU_OFFSET1]
bl omap4_get_scu_base
bl scu_power_mode
skip_scu_gp_set:
mrc p15, 0, r0, c1, c1, 2 @ Read NSACR data
tst r0, #(1 << 18)
mrcne p15, 0, r0, c1, c0, 1
bicne r0, r0, #(1 << 6) @ Disable SMP bit
mcrne p15, 0, r0, c1, c0, 1
isb
dsb
#ifdef CONFIG_CACHE_L2X0
/*
* Clean and invalidate the L2 cache.
* Common cache-l2x0.c functions can't be used here since it
* uses spinlocks. We are out of coherency here with data cache
* disabled. The spinlock implementation uses exclusive load/store
* instruction which can fail without data cache being enabled.
* OMAP4 hardware doesn't support exclusive monitor which can
* overcome exclusive access issue. Because of this, CPU can
* lead to deadlock.
*/
bl omap4_get_sar_ram_base
mov r8, r0
mrc p15, 0, r5, c0, c0, 5 @ Read MPIDR
ands r5, r5, #0x0f
ldreq r0, [r8, #L2X0_SAVE_OFFSET0] @ Retrieve L2 state from SAR
ldrne r0, [r8, #L2X0_SAVE_OFFSET1] @ memory.
cmp r0, #3
bne do_WFI
#ifdef CONFIG_PL310_ERRATA_727915
mov r0, #0x03
mov r12, #OMAP4_MON_L2X0_DBG_CTRL_INDEX
DO_SMC
#endif
bl omap4_get_l2cache_base
mov r2, r0
ldr r0, =0xffff
str r0, [r2, #L2X0_CLEAN_INV_WAY]
wait:
ldr r0, [r2, #L2X0_CLEAN_INV_WAY]
ldr r1, =0xffff
ands r0, r0, r1
bne wait
#ifdef CONFIG_PL310_ERRATA_727915
mov r0, #0x00
mov r12, #OMAP4_MON_L2X0_DBG_CTRL_INDEX
DO_SMC
#endif
l2x_sync:
bl omap4_get_l2cache_base
mov r2, r0
mov r0, #0x0
str r0, [r2, #L2X0_CACHE_SYNC]
sync:
ldr r0, [r2, #L2X0_CACHE_SYNC]
ands r0, r0, #0x1
bne sync
#endif
do_WFI:
bl omap_do_wfi
/*
* CPU is here when it failed to enter OFF/DORMANT or
* no low power state was attempted.
*/
mrc p15, 0, r0, c1, c0, 0
tst r0, #(1 << 2) @ Check C bit enabled?
orreq r0, r0, #(1 << 2) @ Enable the C bit
mcreq p15, 0, r0, c1, c0, 0
isb
/*
* Ensure the CPU power state is set to NORMAL in
* SCU power state so that CPU is back in coherency.
* In non-coherent mode CPU can lock-up and lead to
* system deadlock.
*/
mrc p15, 0, r0, c1, c0, 1
tst r0, #(1 << 6) @ Check SMP bit enabled?
orreq r0, r0, #(1 << 6)
mcreq p15, 0, r0, c1, c0, 1
isb
bl omap4_get_sar_ram_base
mov r8, r0
ldr r9, [r8, #OMAP_TYPE_OFFSET]
cmp r9, #0x1 @ Check for HS device
bne scu_gp_clear
mov r0, #SCU_PM_NORMAL
mov r1, #0x00
stmfd r13!, {r4-r12, r14}
ldr r12, =OMAP4_MON_SCU_PWR_INDEX
DO_SMC
ldmfd r13!, {r4-r12, r14}
b skip_scu_gp_clear
scu_gp_clear:
bl omap4_get_scu_base
mov r1, #SCU_PM_NORMAL
bl scu_power_mode
skip_scu_gp_clear:
isb
dsb
ldmfd sp!, {r4-r12, pc}
ENDPROC(omap4_finish_suspend)
/*
* ============================
* == CPU resume entry point ==
* ============================
*
* void omap4_cpu_resume(void)
*
* ROM code jumps to this function while waking up from CPU
* OFF or DORMANT state. Physical address of the function is
* stored in the SAR RAM while entering to OFF or DORMANT mode.
* The restore function pointer is stored at CPUx_WAKEUP_NS_PA_ADDR_OFFSET.
*/
ENTRY(omap4_cpu_resume)
/*
* Configure ACTRL and enable NS SMP bit access on CPU1 on HS device.
* OMAP44XX EMU/HS devices - CPU0 SMP bit access is enabled in PPA
* init and for CPU1, a secure PPA API provided. CPU0 must be ON
* while executing NS_SMP API on CPU1 and PPA version must be 1.4.0+.
* OMAP443X GP devices- SMP bit isn't accessible.
* OMAP446X GP devices - SMP bit access is enabled on both CPUs.
*/
ldr r8, =OMAP44XX_SAR_RAM_BASE
ldr r9, [r8, #OMAP_TYPE_OFFSET]
cmp r9, #0x1 @ Skip if GP device
bne skip_ns_smp_enable
mrc p15, 0, r0, c0, c0, 5
ands r0, r0, #0x0f
beq skip_ns_smp_enable
ppa_actrl_retry:
mov r0, #OMAP4_PPA_CPU_ACTRL_SMP_INDEX
adr r3, ppa_zero_params @ Pointer to parameters
mov r1, #0x0 @ Process ID
mov r2, #0x4 @ Flag
mov r6, #0xff
mov r12, #0x00 @ Secure Service ID
DO_SMC
cmp r0, #0x0 @ API returns 0 on success.
beq enable_smp_bit
b ppa_actrl_retry
enable_smp_bit:
mrc p15, 0, r0, c1, c0, 1
tst r0, #(1 << 6) @ Check SMP bit enabled?
orreq r0, r0, #(1 << 6)
mcreq p15, 0, r0, c1, c0, 1
isb
skip_ns_smp_enable:
#ifdef CONFIG_CACHE_L2X0
/*
* Restore the L2 AUXCTRL and enable the L2 cache.
* OMAP4_MON_L2X0_AUXCTRL_INDEX = Program the L2X0 AUXCTRL
* OMAP4_MON_L2X0_CTRL_INDEX = Enable the L2 using L2X0 CTRL
* register r0 contains value to be programmed.
* L2 cache is already invalidate by ROM code as part
* of MPUSS OFF wakeup path.
*/
ldr r2, =OMAP44XX_L2CACHE_BASE
ldr r0, [r2, #L2X0_CTRL]
and r0, #0x0f
cmp r0, #1
beq skip_l2en @ Skip if already enabled
ldr r3, =OMAP44XX_SAR_RAM_BASE
ldr r1, [r3, #OMAP_TYPE_OFFSET]
cmp r1, #0x1 @ Check for HS device
bne set_gp_por
ldr r0, =OMAP4_PPA_L2_POR_INDEX
ldr r1, =OMAP44XX_SAR_RAM_BASE
ldr r4, [r1, #L2X0_PREFETCH_CTRL_OFFSET]
adr r3, ppa_por_params
str r4, [r3, #0x04]
mov r1, #0x0 @ Process ID
mov r2, #0x4 @ Flag
mov r6, #0xff
mov r12, #0x00 @ Secure Service ID
DO_SMC
b set_aux_ctrl
set_gp_por:
ldr r1, =OMAP44XX_SAR_RAM_BASE
ldr r0, [r1, #L2X0_PREFETCH_CTRL_OFFSET]
ldr r12, =OMAP4_MON_L2X0_PREFETCH_INDEX @ Setup L2 PREFETCH
DO_SMC
set_aux_ctrl:
ldr r1, =OMAP44XX_SAR_RAM_BASE
ldr r0, [r1, #L2X0_AUXCTRL_OFFSET]
ldr r12, =OMAP4_MON_L2X0_AUXCTRL_INDEX @ Setup L2 AUXCTRL
DO_SMC
mov r0, #0x1
ldr r12, =OMAP4_MON_L2X0_CTRL_INDEX @ Enable L2 cache
DO_SMC
skip_l2en:
#endif
b cpu_resume @ Jump to generic resume
ENDPROC(omap4_cpu_resume)
#endif
#ifndef CONFIG_OMAP4_ERRATA_I688
ENTRY(omap_bus_sync)
mov pc, lr
ENDPROC(omap_bus_sync)
#endif
ENTRY(omap_do_wfi)
stmfd sp!, {lr}
/* Drain interconnect write buffers. */
bl omap_bus_sync
/*
* Execute an ISB instruction to ensure that all of the
* CP15 register changes have been committed.
*/
isb
/*
* Execute a barrier instruction to ensure that all cache,
* TLB and branch predictor maintenance operations issued
* by any CPU in the cluster have completed.
*/
dsb
dmb
/*
* Execute a WFI instruction and wait until the
* STANDBYWFI output is asserted to indicate that the
* CPU is in idle and low power state. CPU can specualatively
* prefetch the instructions so add NOPs after WFI. Sixteen
* NOPs as per Cortex-A9 pipeline.
*/
wfi @ Wait For Interrupt
nop
nop
nop
nop
nop
nop
nop
nop
nop
nop
nop
nop
nop
nop
nop
nop
ldmfd sp!, {pc}
ENDPROC(omap_do_wfi)
