diff options
Diffstat (limited to 'kernel/arch/arm/mach-at91/pm_suspend.S')
| -rw-r--r-- | kernel/arch/arm/mach-at91/pm_suspend.S | 337 |
1 files changed, 337 insertions, 0 deletions
diff --git a/kernel/arch/arm/mach-at91/pm_suspend.S b/kernel/arch/arm/mach-at91/pm_suspend.S new file mode 100644 index 000000000..bd22b2c8a --- /dev/null +++ b/kernel/arch/arm/mach-at91/pm_suspend.S @@ -0,0 +1,337 @@ +/* + * arch/arm/mach-at91/pm_slow_clock.S + * + * Copyright (C) 2006 Savin Zlobec + * + * AT91SAM9 support: + * Copyright (C) 2007 Anti Sullin <anti.sullin@artecdesign.ee + * + * 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 <linux/clk/at91_pmc.h> +#include <mach/at91_ramc.h> +#include "pm.h" + +#define SRAMC_SELF_FRESH_ACTIVE 0x01 +#define SRAMC_SELF_FRESH_EXIT 0x00 + +pmc .req r0 +tmp1 .req r4 +tmp2 .req r5 + +/* + * Wait until master clock is ready (after switching master clock source) + */ + .macro wait_mckrdy +1: ldr tmp1, [pmc, #AT91_PMC_SR] + tst tmp1, #AT91_PMC_MCKRDY + beq 1b + .endm + +/* + * Wait until master oscillator has stabilized. + */ + .macro wait_moscrdy +1: ldr tmp1, [pmc, #AT91_PMC_SR] + tst tmp1, #AT91_PMC_MOSCS + beq 1b + .endm + +/* + * Wait until PLLA has locked. + */ + .macro wait_pllalock +1: ldr tmp1, [pmc, #AT91_PMC_SR] + tst tmp1, #AT91_PMC_LOCKA + beq 1b + .endm + +/* + * Put the processor to enter the idle state + */ + .macro at91_cpu_idle + +#if defined(CONFIG_CPU_V7) + mov tmp1, #AT91_PMC_PCK + str tmp1, [pmc, #AT91_PMC_SCDR] + + dsb + + wfi @ Wait For Interrupt +#else + mcr p15, 0, tmp1, c7, c0, 4 +#endif + + .endm + + .text + + .arm + +/* + * void at91_pm_suspend_in_sram(void __iomem *pmc, void __iomem *sdramc, + * void __iomem *ramc1, int memctrl) + * @input param: + * @r0: base address of AT91_PMC + * @r1: base address of SDRAM Controller (SDRAM, DDRSDR, or AT91_SYS) + * @r2: base address of second SDRAM Controller or 0 if not present + * @r3: pm information + */ +ENTRY(at91_pm_suspend_in_sram) + /* Save registers on stack */ + stmfd sp!, {r4 - r12, lr} + + /* Drain write buffer */ + mov tmp1, #0 + mcr p15, 0, tmp1, c7, c10, 4 + + str r0, .pmc_base + str r1, .sramc_base + str r2, .sramc1_base + + and r0, r3, #AT91_PM_MEMTYPE_MASK + str r0, .memtype + + lsr r0, r3, #AT91_PM_MODE_OFFSET + and r0, r0, #AT91_PM_MODE_MASK + str r0, .pm_mode + + /* Active the self-refresh mode */ + mov r0, #SRAMC_SELF_FRESH_ACTIVE + bl at91_sramc_self_refresh + + ldr r0, .pm_mode + tst r0, #AT91_PM_SLOW_CLOCK + beq skip_disable_main_clock + + ldr pmc, .pmc_base + + /* Save Master clock setting */ + ldr tmp1, [pmc, #AT91_PMC_MCKR] + str tmp1, .saved_mckr + + /* + * Set the Master clock source to slow clock + */ + bic tmp1, tmp1, #AT91_PMC_CSS + str tmp1, [pmc, #AT91_PMC_MCKR] + + wait_mckrdy + + /* Save PLLA setting and disable it */ + ldr tmp1, [pmc, #AT91_CKGR_PLLAR] + str tmp1, .saved_pllar + + mov tmp1, #AT91_PMC_PLLCOUNT + orr tmp1, tmp1, #(1 << 29) /* bit 29 always set */ + str tmp1, [pmc, #AT91_CKGR_PLLAR] + + /* Turn off the main oscillator */ + ldr tmp1, [pmc, #AT91_CKGR_MOR] + bic tmp1, tmp1, #AT91_PMC_MOSCEN + orr tmp1, tmp1, #AT91_PMC_KEY + str tmp1, [pmc, #AT91_CKGR_MOR] + +skip_disable_main_clock: + ldr pmc, .pmc_base + + /* Wait for interrupt */ + at91_cpu_idle + + ldr r0, .pm_mode + tst r0, #AT91_PM_SLOW_CLOCK + beq skip_enable_main_clock + + ldr pmc, .pmc_base + + /* Turn on the main oscillator */ + ldr tmp1, [pmc, #AT91_CKGR_MOR] + orr tmp1, tmp1, #AT91_PMC_MOSCEN + orr tmp1, tmp1, #AT91_PMC_KEY + str tmp1, [pmc, #AT91_CKGR_MOR] + + wait_moscrdy + + /* Restore PLLA setting */ + ldr tmp1, .saved_pllar + str tmp1, [pmc, #AT91_CKGR_PLLAR] + + tst tmp1, #(AT91_PMC_MUL & 0xff0000) + bne 3f + tst tmp1, #(AT91_PMC_MUL & ~0xff0000) + beq 4f +3: + wait_pllalock +4: + + /* + * Restore master clock setting + */ + ldr tmp1, .saved_mckr + str tmp1, [pmc, #AT91_PMC_MCKR] + + wait_mckrdy + +skip_enable_main_clock: + /* Exit the self-refresh mode */ + mov r0, #SRAMC_SELF_FRESH_EXIT + bl at91_sramc_self_refresh + + /* Restore registers, and return */ + ldmfd sp!, {r4 - r12, pc} +ENDPROC(at91_pm_suspend_in_sram) + +/* + * void at91_sramc_self_refresh(unsigned int is_active) + * + * @input param: + * @r0: 1 - active self-refresh mode + * 0 - exit self-refresh mode + * register usage: + * @r1: memory type + * @r2: base address of the sram controller + */ + +ENTRY(at91_sramc_self_refresh) + ldr r1, .memtype + ldr r2, .sramc_base + + cmp r1, #AT91_MEMCTRL_MC + bne ddrc_sf + + /* + * at91rm9200 Memory controller + */ + + /* + * For exiting the self-refresh mode, do nothing, + * automatically exit the self-refresh mode. + */ + tst r0, #SRAMC_SELF_FRESH_ACTIVE + beq exit_sramc_sf + + /* Active SDRAM self-refresh mode */ + mov r3, #1 + str r3, [r2, #AT91RM9200_SDRAMC_SRR] + b exit_sramc_sf + +ddrc_sf: + cmp r1, #AT91_MEMCTRL_DDRSDR + bne sdramc_sf + + /* + * DDR Memory controller + */ + tst r0, #SRAMC_SELF_FRESH_ACTIVE + beq ddrc_exit_sf + + /* LPDDR1 --> force DDR2 mode during self-refresh */ + ldr r3, [r2, #AT91_DDRSDRC_MDR] + str r3, .saved_sam9_mdr + bic r3, r3, #~AT91_DDRSDRC_MD + cmp r3, #AT91_DDRSDRC_MD_LOW_POWER_DDR + ldreq r3, [r2, #AT91_DDRSDRC_MDR] + biceq r3, r3, #AT91_DDRSDRC_MD + orreq r3, r3, #AT91_DDRSDRC_MD_DDR2 + streq r3, [r2, #AT91_DDRSDRC_MDR] + + /* Active DDRC self-refresh mode */ + ldr r3, [r2, #AT91_DDRSDRC_LPR] + str r3, .saved_sam9_lpr + bic r3, r3, #AT91_DDRSDRC_LPCB + orr r3, r3, #AT91_DDRSDRC_LPCB_SELF_REFRESH + str r3, [r2, #AT91_DDRSDRC_LPR] + + /* If using the 2nd ddr controller */ + ldr r2, .sramc1_base + cmp r2, #0 + beq no_2nd_ddrc + + ldr r3, [r2, #AT91_DDRSDRC_MDR] + str r3, .saved_sam9_mdr1 + bic r3, r3, #~AT91_DDRSDRC_MD + cmp r3, #AT91_DDRSDRC_MD_LOW_POWER_DDR + ldreq r3, [r2, #AT91_DDRSDRC_MDR] + biceq r3, r3, #AT91_DDRSDRC_MD + orreq r3, r3, #AT91_DDRSDRC_MD_DDR2 + streq r3, [r2, #AT91_DDRSDRC_MDR] + + /* Active DDRC self-refresh mode */ + ldr r3, [r2, #AT91_DDRSDRC_LPR] + str r3, .saved_sam9_lpr1 + bic r3, r3, #AT91_DDRSDRC_LPCB + orr r3, r3, #AT91_DDRSDRC_LPCB_SELF_REFRESH + str r3, [r2, #AT91_DDRSDRC_LPR] + +no_2nd_ddrc: + b exit_sramc_sf + +ddrc_exit_sf: + /* Restore MDR in case of LPDDR1 */ + ldr r3, .saved_sam9_mdr + str r3, [r2, #AT91_DDRSDRC_MDR] + /* Restore LPR on AT91 with DDRAM */ + ldr r3, .saved_sam9_lpr + str r3, [r2, #AT91_DDRSDRC_LPR] + + /* If using the 2nd ddr controller */ + ldr r2, .sramc1_base + cmp r2, #0 + ldrne r3, .saved_sam9_mdr1 + strne r3, [r2, #AT91_DDRSDRC_MDR] + ldrne r3, .saved_sam9_lpr1 + strne r3, [r2, #AT91_DDRSDRC_LPR] + + b exit_sramc_sf + + /* + * SDRAMC Memory controller + */ +sdramc_sf: + tst r0, #SRAMC_SELF_FRESH_ACTIVE + beq sdramc_exit_sf + + /* Active SDRAMC self-refresh mode */ + ldr r3, [r2, #AT91_SDRAMC_LPR] + str r3, .saved_sam9_lpr + bic r3, r3, #AT91_SDRAMC_LPCB + orr r3, r3, #AT91_SDRAMC_LPCB_SELF_REFRESH + str r3, [r2, #AT91_SDRAMC_LPR] + +sdramc_exit_sf: + ldr r3, .saved_sam9_lpr + str r3, [r2, #AT91_SDRAMC_LPR] + +exit_sramc_sf: + mov pc, lr +ENDPROC(at91_sramc_self_refresh) + +.pmc_base: + .word 0 +.sramc_base: + .word 0 +.sramc1_base: + .word 0 +.memtype: + .word 0 +.pm_mode: + .word 0 +.saved_mckr: + .word 0 +.saved_pllar: + .word 0 +.saved_sam9_lpr: + .word 0 +.saved_sam9_lpr1: + .word 0 +.saved_sam9_mdr: + .word 0 +.saved_sam9_mdr1: + .word 0 + +ENTRY(at91_pm_suspend_in_sram_sz) + .word .-at91_pm_suspend_in_sram |