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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /arch/frv/kernel/sleep.S
Initial import
Diffstat (limited to 'arch/frv/kernel/sleep.S')
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diff --git a/arch/frv/kernel/sleep.S b/arch/frv/kernel/sleep.S
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+/* sleep.S: power saving mode entry
+ *
+ * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
+ * Written by David Woodhouse (dwmw2@infradead.org)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ *
+ */
+
+#include <linux/sys.h>
+#include <linux/linkage.h>
+#include <asm/setup.h>
+#include <asm/segment.h>
+#include <asm/page.h>
+#include <asm/ptrace.h>
+#include <asm/errno.h>
+#include <asm/cache.h>
+#include <asm/spr-regs.h>
+
+#define __addr_MASK 0xfeff9820 /* interrupt controller mask */
+
+#define __addr_FR55X_DRCN 0xfeff0218 /* Address of DRCN register */
+#define FR55X_DSTS_OFFSET -4 /* Offset from DRCN to DSTS */
+#define FR55X_SDRAMC_DSTS_SSI 0x00000002 /* indicates that the SDRAM is in self-refresh mode */
+
+#define __addr_FR4XX_DRCN 0xfe000430 /* Address of DRCN register */
+#define FR4XX_DSTS_OFFSET -8 /* Offset from DRCN to DSTS */
+#define FR4XX_SDRAMC_DSTS_SSI 0x00000001 /* indicates that the SDRAM is in self-refresh mode */
+
+#define SDRAMC_DRCN_SR 0x00000001 /* transition SDRAM into self-refresh mode */
+
+ .section .bss
+ .balign 8
+ .globl __sleep_save_area
+__sleep_save_area:
+ .space 16
+
+
+ .text
+ .balign 4
+
+.macro li v r
+ sethi.p %hi(\v),\r
+ setlo %lo(\v),\r
+.endm
+
+#ifdef CONFIG_PM
+###############################################################################
+#
+# CPU suspension routine
+# - void frv_cpu_suspend(unsigned long pdm_mode)
+#
+###############################################################################
+ .globl frv_cpu_suspend
+ .type frv_cpu_suspend,@function
+frv_cpu_suspend:
+
+ #----------------------------------------------------
+ # save hsr0, psr, isr, and lr for resume code
+ #----------------------------------------------------
+ li __sleep_save_area,gr11
+
+ movsg hsr0,gr4
+ movsg psr,gr5
+ movsg isr,gr6
+ movsg lr,gr7
+ stdi gr4,@(gr11,#0)
+ stdi gr6,@(gr11,#8)
+
+ # store the return address from sleep in GR14, and its complement in GR13 as a check
+ li __ramboot_resume,gr14
+#ifdef CONFIG_MMU
+ # Resume via RAMBOOT# will turn MMU off, so bootloader needs a physical address.
+ sethi.p %hi(__page_offset),gr13
+ setlo %lo(__page_offset),gr13
+ sub gr14,gr13,gr14
+#endif
+ not gr14,gr13
+
+ #----------------------------------------------------
+ # preload and lock into icache that code which may have to run
+ # when dram is in self-refresh state.
+ #----------------------------------------------------
+ movsg hsr0, gr3
+ li HSR0_ICE,gr4
+ or gr3,gr4,gr3
+ movgs gr3,hsr0
+ or gr3,gr8,gr7 // add the sleep bits for later
+
+ li #__icache_lock_start,gr3
+ li #__icache_lock_end,gr4
+1: icpl gr3,gr0,#1
+ addi gr3,#L1_CACHE_BYTES,gr3
+ cmp gr4,gr3,icc0
+ bhi icc0,#0,1b
+
+ # disable exceptions
+ movsg psr,gr8
+ andi.p gr8,#~PSR_PIL,gr8
+ andi gr8,~PSR_ET,gr8
+ movgs gr8,psr
+ ori gr8,#PSR_ET,gr8
+
+ srli gr8,#28,gr4
+ subicc gr4,#3,gr0,icc0
+ beq icc0,#0,1f
+ # FR4xx
+ li __addr_FR4XX_DRCN,gr4
+ li FR4XX_SDRAMC_DSTS_SSI,gr5
+ li FR4XX_DSTS_OFFSET,gr6
+ bra __icache_lock_start
+1:
+ # FR5xx
+ li __addr_FR55X_DRCN,gr4
+ li FR55X_SDRAMC_DSTS_SSI,gr5
+ li FR55X_DSTS_OFFSET,gr6
+ bra __icache_lock_start
+
+ .size frv_cpu_suspend, .-frv_cpu_suspend
+
+#
+# the final part of the sleep sequence...
+# - we want it to be be cacheline aligned so we can lock it into the icache easily
+# On entry: gr7 holds desired hsr0 sleep value
+# gr8 holds desired psr sleep value
+#
+ .balign L1_CACHE_BYTES
+ .type __icache_lock_start,@function
+__icache_lock_start:
+
+ #----------------------------------------------------
+ # put SDRAM in self-refresh mode
+ #----------------------------------------------------
+
+ # Flush all data in the cache using the DCEF instruction.
+ dcef @(gr0,gr0),#1
+
+ # Stop DMAC transfer
+
+ # Execute dummy load from SDRAM
+ ldi @(gr11,#0),gr11
+
+ # put the SDRAM into self-refresh mode
+ ld @(gr4,gr0),gr11
+ ori gr11,#SDRAMC_DRCN_SR,gr11
+ st gr11,@(gr4,gr0)
+ membar
+
+ # wait for SDRAM to reach self-refresh mode
+1: ld @(gr4,gr6),gr11
+ andcc gr11,gr5,gr11,icc0
+ beq icc0,#0,1b
+
+ # Set the GPIO register so that the IRQ[3:0] pins become valid, as required.
+ # Set the clock mode (CLKC register) as required.
+ # - At this time, also set the CLKC register P0 bit.
+
+ # Set the HSR0 register PDM field.
+ movgs gr7,hsr0
+
+ # Execute NOP 32 times.
+ .rept 32
+ nop
+ .endr
+
+#if 0 // Fujitsu recommend to skip this and will update docs.
+ # Release the interrupt mask setting of the MASK register of the
+ # interrupt controller if necessary.
+ sti gr10,@(gr9,#0)
+ membar
+#endif
+
+ # Set the PSR register ET bit to 1 to enable interrupts.
+ movgs gr8,psr
+
+ ###################################################
+ # this is only reached if waking up via interrupt
+ ###################################################
+
+ # Execute NOP 32 times.
+ .rept 32
+ nop
+ .endr
+
+ #----------------------------------------------------
+ # wake SDRAM from self-refresh mode
+ #----------------------------------------------------
+ ld @(gr4,gr0),gr11
+ andi gr11,#~SDRAMC_DRCN_SR,gr11
+ st gr11,@(gr4,gr0)
+ membar
+2:
+ ld @(gr4,gr6),gr11 // Wait for it to come back...
+ andcc gr11,gr5,gr0,icc0
+ bne icc0,0,2b
+
+ # wait for the SDRAM to stabilise
+ li 0x0100000,gr3
+3: subicc gr3,#1,gr3,icc0
+ bne icc0,#0,3b
+
+ # now that DRAM is back, this is the end of the code which gets
+ # locked in icache.
+__icache_lock_end:
+ .size __icache_lock_start, .-__icache_lock_start
+
+ # Fall-through to the RAMBOOT# wakeup path
+
+###############################################################################
+#
+# resume from suspend re-entry point reached via RAMBOOT# and bootloader
+#
+###############################################################################
+__ramboot_resume:
+
+ #----------------------------------------------------
+ # restore hsr0, psr, isr, and leave saved lr in gr7
+ #----------------------------------------------------
+ li __sleep_save_area,gr11
+#ifdef CONFIG_MMU
+ movsg hsr0,gr4
+ sethi.p %hi(HSR0_EXMMU),gr3
+ setlo %lo(HSR0_EXMMU),gr3
+ andcc gr3,gr4,gr0,icc0
+ bne icc0,#0,2f
+
+ # need to use physical address
+ sethi.p %hi(__page_offset),gr3
+ setlo %lo(__page_offset),gr3
+ sub gr11,gr3,gr11
+
+ # flush all tlb entries
+ setlos #64,gr4
+ setlos.p #PAGE_SIZE,gr5
+ setlos #0,gr6
+1:
+ tlbpr gr6,gr0,#6,#0
+ subicc.p gr4,#1,gr4,icc0
+ add gr6,gr5,gr6
+ bne icc0,#2,1b
+
+ # need a temporary mapping for the current physical address we are
+ # using between time MMU is enabled and jump to virtual address is
+ # made.
+ sethi.p %hi(0x00000000),gr4
+ setlo %lo(0x00000000),gr4 ; physical address
+ setlos #xAMPRx_L|xAMPRx_M|xAMPRx_SS_256Mb|xAMPRx_S_KERNEL|xAMPRx_V,gr5
+ or gr4,gr5,gr5
+
+ movsg cxnr,gr13
+ or gr4,gr13,gr4
+
+ movgs gr4,iamlr1 ; mapped from real address 0
+ movgs gr5,iampr1 ; cached kernel memory at 0x00000000
+2:
+#endif
+
+ lddi @(gr11,#0),gr4 ; hsr0, psr
+ lddi @(gr11,#8),gr6 ; isr, lr
+ movgs gr4,hsr0
+ bar
+
+#ifdef CONFIG_MMU
+ sethi.p %hi(1f),gr11
+ setlo %lo(1f),gr11
+ jmpl @(gr11,gr0)
+1:
+ movgs gr0,iampr1 ; get rid of temporary mapping
+#endif
+ movgs gr5,psr
+ movgs gr6,isr
+
+ #----------------------------------------------------
+ # unlock the icache which was locked before going to sleep
+ #----------------------------------------------------
+ li __icache_lock_start,gr3
+ li __icache_lock_end,gr4
+1: icul gr3
+ addi gr3,#L1_CACHE_BYTES,gr3
+ cmp gr4,gr3,icc0
+ bhi icc0,#0,1b
+
+ #----------------------------------------------------
+ # back to business as usual
+ #----------------------------------------------------
+ jmpl @(gr7,gr0) ;
+
+#endif /* CONFIG_PM */
+
+###############################################################################
+#
+# CPU core sleep mode routine
+#
+###############################################################################
+ .globl frv_cpu_core_sleep
+ .type frv_cpu_core_sleep,@function
+frv_cpu_core_sleep:
+
+ # Preload into icache.
+ li #__core_sleep_icache_lock_start,gr3
+ li #__core_sleep_icache_lock_end,gr4
+
+1: icpl gr3,gr0,#1
+ addi gr3,#L1_CACHE_BYTES,gr3
+ cmp gr4,gr3,icc0
+ bhi icc0,#0,1b
+
+ bra __core_sleep_icache_lock_start
+
+ .balign L1_CACHE_BYTES
+__core_sleep_icache_lock_start:
+
+ # (1) Set the PSR register ET bit to 0 to disable interrupts.
+ movsg psr,gr8
+ andi.p gr8,#~(PSR_PIL),gr8
+ andi gr8,#~(PSR_ET),gr4
+ movgs gr4,psr
+
+#if 0 // Fujitsu recommend to skip this and will update docs.
+ # (2) Set '1' to all bits in the MASK register of the interrupt
+ # controller and mask interrupts.
+ sethi.p %hi(__addr_MASK),gr9
+ setlo %lo(__addr_MASK),gr9
+ sethi.p %hi(0xffff0000),gr4
+ setlo %lo(0xffff0000),gr4
+ ldi @(gr9,#0),gr10
+ sti gr4,@(gr9,#0)
+#endif
+ # (3) Flush all data in the cache using the DCEF instruction.
+ dcef @(gr0,gr0),#1
+
+ # (4) Execute the memory barrier instruction
+ membar
+
+ # (5) Set the GPIO register so that the IRQ[3:0] pins become valid, as required.
+ # (6) Set the clock mode (CLKC register) as required.
+ # - At this time, also set the CLKC register P0 bit.
+ # (7) Set the HSR0 register PDM field to 001 .
+ movsg hsr0,gr4
+ ori gr4,HSR0_PDM_CORE_SLEEP,gr4
+ movgs gr4,hsr0
+
+ # (8) Execute NOP 32 times.
+ .rept 32
+ nop
+ .endr
+
+#if 0 // Fujitsu recommend to skip this and will update docs.
+ # (9) Release the interrupt mask setting of the MASK register of the
+ # interrupt controller if necessary.
+ sti gr10,@(gr9,#0)
+ membar
+#endif
+
+ # (10) Set the PSR register ET bit to 1 to enable interrupts.
+ movgs gr8,psr
+
+__core_sleep_icache_lock_end:
+
+ # Unlock from icache
+ li __core_sleep_icache_lock_start,gr3
+ li __core_sleep_icache_lock_end,gr4
+1: icul gr3
+ addi gr3,#L1_CACHE_BYTES,gr3
+ cmp gr4,gr3,icc0
+ bhi icc0,#0,1b
+
+ bralr
+
+ .size frv_cpu_core_sleep, .-frv_cpu_core_sleep