diff options
Diffstat (limited to 'arch/arm/mach-tegra/sleep-tegra20.S')
| -rw-r--r-- | arch/arm/mach-tegra/sleep-tegra20.S | 584 |
1 files changed, 584 insertions, 0 deletions
diff --git a/arch/arm/mach-tegra/sleep-tegra20.S b/arch/arm/mach-tegra/sleep-tegra20.S new file mode 100644 index 000000000..5c8e638ee --- /dev/null +++ b/arch/arm/mach-tegra/sleep-tegra20.S @@ -0,0 +1,584 @@ +/* + * Copyright (c) 2010-2012, NVIDIA Corporation. All rights reserved. + * Copyright (c) 2011, Google, Inc. + * + * Author: Colin Cross <ccross@android.com> + * Gary King <gking@nvidia.com> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#include <linux/linkage.h> + +#include <soc/tegra/flowctrl.h> + +#include <asm/assembler.h> +#include <asm/proc-fns.h> +#include <asm/cp15.h> +#include <asm/cache.h> + +#include "irammap.h" +#include "sleep.h" + +#define EMC_CFG 0xc +#define EMC_ADR_CFG 0x10 +#define EMC_REFRESH 0x70 +#define EMC_NOP 0xdc +#define EMC_SELF_REF 0xe0 +#define EMC_REQ_CTRL 0x2b0 +#define EMC_EMC_STATUS 0x2b4 + +#define CLK_RESET_CCLK_BURST 0x20 +#define CLK_RESET_CCLK_DIVIDER 0x24 +#define CLK_RESET_SCLK_BURST 0x28 +#define CLK_RESET_SCLK_DIVIDER 0x2c +#define CLK_RESET_PLLC_BASE 0x80 +#define CLK_RESET_PLLM_BASE 0x90 +#define CLK_RESET_PLLP_BASE 0xa0 + +#define APB_MISC_XM2CFGCPADCTRL 0x8c8 +#define APB_MISC_XM2CFGDPADCTRL 0x8cc +#define APB_MISC_XM2CLKCFGPADCTRL 0x8d0 +#define APB_MISC_XM2COMPPADCTRL 0x8d4 +#define APB_MISC_XM2VTTGENPADCTRL 0x8d8 +#define APB_MISC_XM2CFGCPADCTRL2 0x8e4 +#define APB_MISC_XM2CFGDPADCTRL2 0x8e8 + +.macro pll_enable, rd, r_car_base, pll_base + ldr \rd, [\r_car_base, #\pll_base] + tst \rd, #(1 << 30) + orreq \rd, \rd, #(1 << 30) + streq \rd, [\r_car_base, #\pll_base] +.endm + +.macro emc_device_mask, rd, base + ldr \rd, [\base, #EMC_ADR_CFG] + tst \rd, #(0x3 << 24) + moveq \rd, #(0x1 << 8) @ just 1 device + movne \rd, #(0x3 << 8) @ 2 devices +.endm + +#if defined(CONFIG_HOTPLUG_CPU) || defined(CONFIG_PM_SLEEP) +/* + * tegra20_hotplug_shutdown(void) + * + * puts the current cpu in reset + * should never return + */ +ENTRY(tegra20_hotplug_shutdown) + /* Put this CPU down */ + cpu_id r0 + bl tegra20_cpu_shutdown + ret lr @ should never get here +ENDPROC(tegra20_hotplug_shutdown) + +/* + * tegra20_cpu_shutdown(int cpu) + * + * r0 is cpu to reset + * + * puts the specified CPU in wait-for-event mode on the flow controller + * and puts the CPU in reset + * can be called on the current cpu or another cpu + * if called on the current cpu, does not return + * MUST NOT BE CALLED FOR CPU 0. + * + * corrupts r0-r3, r12 + */ +ENTRY(tegra20_cpu_shutdown) + cmp r0, #0 + reteq lr @ must not be called for CPU 0 + mov32 r1, TEGRA_IRAM_RESET_BASE_VIRT + ldr r2, =__tegra20_cpu1_resettable_status_offset + mov r12, #CPU_RESETTABLE + strb r12, [r1, r2] + + cpu_to_halt_reg r1, r0 + ldr r3, =TEGRA_FLOW_CTRL_VIRT + mov r2, #FLOW_CTRL_WAITEVENT | FLOW_CTRL_JTAG_RESUME + str r2, [r3, r1] @ put flow controller in wait event mode + ldr r2, [r3, r1] + isb + dsb + movw r1, 0x1011 + mov r1, r1, lsl r0 + ldr r3, =TEGRA_CLK_RESET_VIRT + str r1, [r3, #0x340] @ put slave CPU in reset + isb + dsb + cpu_id r3 + cmp r3, r0 + beq . + ret lr +ENDPROC(tegra20_cpu_shutdown) +#endif + +#ifdef CONFIG_PM_SLEEP +/* + * tegra_pen_lock + * + * spinlock implementation with no atomic test-and-set and no coherence + * using Peterson's algorithm on strongly-ordered registers + * used to synchronize a cpu waking up from wfi with entering lp2 on idle + * + * The reference link of Peterson's algorithm: + * http://en.wikipedia.org/wiki/Peterson's_algorithm + * + * SCRATCH37 = r1 = !turn (inverted from Peterson's algorithm) + * on cpu 0: + * r2 = flag[0] (in SCRATCH38) + * r3 = flag[1] (in SCRATCH39) + * on cpu1: + * r2 = flag[1] (in SCRATCH39) + * r3 = flag[0] (in SCRATCH38) + * + * must be called with MMU on + * corrupts r0-r3, r12 + */ +ENTRY(tegra_pen_lock) + mov32 r3, TEGRA_PMC_VIRT + cpu_id r0 + add r1, r3, #PMC_SCRATCH37 + cmp r0, #0 + addeq r2, r3, #PMC_SCRATCH38 + addeq r3, r3, #PMC_SCRATCH39 + addne r2, r3, #PMC_SCRATCH39 + addne r3, r3, #PMC_SCRATCH38 + + mov r12, #1 + str r12, [r2] @ flag[cpu] = 1 + dsb + str r12, [r1] @ !turn = cpu +1: dsb + ldr r12, [r3] + cmp r12, #1 @ flag[!cpu] == 1? + ldreq r12, [r1] + cmpeq r12, r0 @ !turn == cpu? + beq 1b @ while !turn == cpu && flag[!cpu] == 1 + + ret lr @ locked +ENDPROC(tegra_pen_lock) + +ENTRY(tegra_pen_unlock) + dsb + mov32 r3, TEGRA_PMC_VIRT + cpu_id r0 + cmp r0, #0 + addeq r2, r3, #PMC_SCRATCH38 + addne r2, r3, #PMC_SCRATCH39 + mov r12, #0 + str r12, [r2] + ret lr +ENDPROC(tegra_pen_unlock) + +/* + * tegra20_cpu_clear_resettable(void) + * + * Called to clear the "resettable soon" flag in IRAM variable when + * it is expected that the secondary CPU will be idle soon. + */ +ENTRY(tegra20_cpu_clear_resettable) + mov32 r1, TEGRA_IRAM_RESET_BASE_VIRT + ldr r2, =__tegra20_cpu1_resettable_status_offset + mov r12, #CPU_NOT_RESETTABLE + strb r12, [r1, r2] + ret lr +ENDPROC(tegra20_cpu_clear_resettable) + +/* + * tegra20_cpu_set_resettable_soon(void) + * + * Called to set the "resettable soon" flag in IRAM variable when + * it is expected that the secondary CPU will be idle soon. + */ +ENTRY(tegra20_cpu_set_resettable_soon) + mov32 r1, TEGRA_IRAM_RESET_BASE_VIRT + ldr r2, =__tegra20_cpu1_resettable_status_offset + mov r12, #CPU_RESETTABLE_SOON + strb r12, [r1, r2] + ret lr +ENDPROC(tegra20_cpu_set_resettable_soon) + +/* + * tegra20_cpu_is_resettable_soon(void) + * + * Returns true if the "resettable soon" flag in IRAM variable has been + * set because it is expected that the secondary CPU will be idle soon. + */ +ENTRY(tegra20_cpu_is_resettable_soon) + mov32 r1, TEGRA_IRAM_RESET_BASE_VIRT + ldr r2, =__tegra20_cpu1_resettable_status_offset + ldrb r12, [r1, r2] + cmp r12, #CPU_RESETTABLE_SOON + moveq r0, #1 + movne r0, #0 + ret lr +ENDPROC(tegra20_cpu_is_resettable_soon) + +/* + * tegra20_sleep_core_finish(unsigned long v2p) + * + * Enters suspend in LP0 or LP1 by turning off the mmu and jumping to + * tegra20_tear_down_core in IRAM + */ +ENTRY(tegra20_sleep_core_finish) + mov r4, r0 + /* Flush, disable the L1 data cache and exit SMP */ + mov r0, #TEGRA_FLUSH_CACHE_ALL + bl tegra_disable_clean_inv_dcache + mov r0, r4 + + mov32 r3, tegra_shut_off_mmu + add r3, r3, r0 + + mov32 r0, tegra20_tear_down_core + mov32 r1, tegra20_iram_start + sub r0, r0, r1 + mov32 r1, TEGRA_IRAM_LPx_RESUME_AREA + add r0, r0, r1 + + ret r3 +ENDPROC(tegra20_sleep_core_finish) + +/* + * tegra20_sleep_cpu_secondary_finish(unsigned long v2p) + * + * Enters WFI on secondary CPU by exiting coherency. + */ +ENTRY(tegra20_sleep_cpu_secondary_finish) + stmfd sp!, {r4-r11, lr} + + mrc p15, 0, r11, c1, c0, 1 @ save actlr before exiting coherency + + /* Flush and disable the L1 data cache */ + mov r0, #TEGRA_FLUSH_CACHE_LOUIS + bl tegra_disable_clean_inv_dcache + + mov32 r0, TEGRA_IRAM_RESET_BASE_VIRT + ldr r4, =__tegra20_cpu1_resettable_status_offset + mov r3, #CPU_RESETTABLE + strb r3, [r0, r4] + + bl tegra_cpu_do_idle + + /* + * cpu may be reset while in wfi, which will return through + * tegra_resume to cpu_resume + * or interrupt may wake wfi, which will return here + * cpu state is unchanged - MMU is on, cache is on, coherency + * is off, and the data cache is off + * + * r11 contains the original actlr + */ + + bl tegra_pen_lock + + mov32 r0, TEGRA_IRAM_RESET_BASE_VIRT + ldr r4, =__tegra20_cpu1_resettable_status_offset + mov r3, #CPU_NOT_RESETTABLE + strb r3, [r0, r4] + + bl tegra_pen_unlock + + /* Re-enable the data cache */ + mrc p15, 0, r10, c1, c0, 0 + orr r10, r10, #CR_C + mcr p15, 0, r10, c1, c0, 0 + isb + + mcr p15, 0, r11, c1, c0, 1 @ reenable coherency + + /* Invalidate the TLBs & BTAC */ + mov r1, #0 + mcr p15, 0, r1, c8, c3, 0 @ invalidate shared TLBs + mcr p15, 0, r1, c7, c1, 6 @ invalidate shared BTAC + dsb + isb + + /* the cpu was running with coherency disabled, + * caches may be out of date */ + bl v7_flush_kern_cache_louis + + ldmfd sp!, {r4 - r11, pc} +ENDPROC(tegra20_sleep_cpu_secondary_finish) + +/* + * tegra20_tear_down_cpu + * + * Switches the CPU cluster to PLL-P and enters sleep. + */ +ENTRY(tegra20_tear_down_cpu) + bl tegra_switch_cpu_to_pllp + b tegra20_enter_sleep +ENDPROC(tegra20_tear_down_cpu) + +/* START OF ROUTINES COPIED TO IRAM */ + .align L1_CACHE_SHIFT + .globl tegra20_iram_start +tegra20_iram_start: + +/* + * tegra20_lp1_reset + * + * reset vector for LP1 restore; copied into IRAM during suspend. + * Brings the system back up to a safe staring point (SDRAM out of + * self-refresh, PLLC, PLLM and PLLP reenabled, CPU running on PLLP, + * system clock running on the same PLL that it suspended at), and + * jumps to tegra_resume to restore virtual addressing and PLLX. + * The physical address of tegra_resume expected to be stored in + * PMC_SCRATCH41. + * + * NOTE: THIS *MUST* BE RELOCATED TO TEGRA_IRAM_LPx_RESUME_AREA. + */ +ENTRY(tegra20_lp1_reset) + /* + * The CPU and system bus are running at 32KHz and executing from + * IRAM when this code is executed; immediately switch to CLKM and + * enable PLLM, PLLP, PLLC. + */ + mov32 r0, TEGRA_CLK_RESET_BASE + + mov r1, #(1 << 28) + str r1, [r0, #CLK_RESET_SCLK_BURST] + str r1, [r0, #CLK_RESET_CCLK_BURST] + mov r1, #0 + str r1, [r0, #CLK_RESET_CCLK_DIVIDER] + str r1, [r0, #CLK_RESET_SCLK_DIVIDER] + + pll_enable r1, r0, CLK_RESET_PLLM_BASE + pll_enable r1, r0, CLK_RESET_PLLP_BASE + pll_enable r1, r0, CLK_RESET_PLLC_BASE + + adr r2, tegra20_sdram_pad_address + adr r4, tegra20_sdram_pad_save + mov r5, #0 + + ldr r6, tegra20_sdram_pad_size +padload: + ldr r7, [r2, r5] @ r7 is the addr in the pad_address + + ldr r1, [r4, r5] + str r1, [r7] @ restore the value in pad_save + + add r5, r5, #4 + cmp r6, r5 + bne padload + +padload_done: + /* 255uS delay for PLL stabilization */ + mov32 r7, TEGRA_TMRUS_BASE + ldr r1, [r7] + add r1, r1, #0xff + wait_until r1, r7, r9 + + adr r4, tegra20_sclk_save + ldr r4, [r4] + str r4, [r0, #CLK_RESET_SCLK_BURST] + mov32 r4, ((1 << 28) | (4)) @ burst policy is PLLP + str r4, [r0, #CLK_RESET_CCLK_BURST] + + mov32 r0, TEGRA_EMC_BASE + ldr r1, [r0, #EMC_CFG] + bic r1, r1, #(1 << 31) @ disable DRAM_CLK_STOP + str r1, [r0, #EMC_CFG] + + mov r1, #0 + str r1, [r0, #EMC_SELF_REF] @ take DRAM out of self refresh + mov r1, #1 + str r1, [r0, #EMC_NOP] + str r1, [r0, #EMC_NOP] + str r1, [r0, #EMC_REFRESH] + + emc_device_mask r1, r0 + +exit_selfrefresh_loop: + ldr r2, [r0, #EMC_EMC_STATUS] + ands r2, r2, r1 + bne exit_selfrefresh_loop + + mov r1, #0 @ unstall all transactions + str r1, [r0, #EMC_REQ_CTRL] + + mov32 r0, TEGRA_PMC_BASE + ldr r0, [r0, #PMC_SCRATCH41] + ret r0 @ jump to tegra_resume +ENDPROC(tegra20_lp1_reset) + +/* + * tegra20_tear_down_core + * + * copied into and executed from IRAM + * puts memory in self-refresh for LP0 and LP1 + */ +tegra20_tear_down_core: + bl tegra20_sdram_self_refresh + bl tegra20_switch_cpu_to_clk32k + b tegra20_enter_sleep + +/* + * tegra20_switch_cpu_to_clk32k + * + * In LP0 and LP1 all PLLs will be turned off. Switch the CPU and system clock + * to the 32KHz clock. + */ +tegra20_switch_cpu_to_clk32k: + /* + * start by switching to CLKM to safely disable PLLs, then switch to + * CLKS. + */ + mov r0, #(1 << 28) + str r0, [r5, #CLK_RESET_SCLK_BURST] + str r0, [r5, #CLK_RESET_CCLK_BURST] + mov r0, #0 + str r0, [r5, #CLK_RESET_CCLK_DIVIDER] + str r0, [r5, #CLK_RESET_SCLK_DIVIDER] + + /* 2uS delay delay between changing SCLK and disabling PLLs */ + mov32 r7, TEGRA_TMRUS_BASE + ldr r1, [r7] + add r1, r1, #2 + wait_until r1, r7, r9 + + /* disable PLLM, PLLP and PLLC */ + ldr r0, [r5, #CLK_RESET_PLLM_BASE] + bic r0, r0, #(1 << 30) + str r0, [r5, #CLK_RESET_PLLM_BASE] + ldr r0, [r5, #CLK_RESET_PLLP_BASE] + bic r0, r0, #(1 << 30) + str r0, [r5, #CLK_RESET_PLLP_BASE] + ldr r0, [r5, #CLK_RESET_PLLC_BASE] + bic r0, r0, #(1 << 30) + str r0, [r5, #CLK_RESET_PLLC_BASE] + + /* switch to CLKS */ + mov r0, #0 /* brust policy = 32KHz */ + str r0, [r5, #CLK_RESET_SCLK_BURST] + + ret lr + +/* + * tegra20_enter_sleep + * + * uses flow controller to enter sleep state + * executes from IRAM with SDRAM in selfrefresh when target state is LP0 or LP1 + * executes from SDRAM with target state is LP2 + */ +tegra20_enter_sleep: + mov32 r6, TEGRA_FLOW_CTRL_BASE + + mov r0, #FLOW_CTRL_WAIT_FOR_INTERRUPT + orr r0, r0, #FLOW_CTRL_HALT_CPU_IRQ | FLOW_CTRL_HALT_CPU_FIQ + cpu_id r1 + cpu_to_halt_reg r1, r1 + str r0, [r6, r1] + dsb + ldr r0, [r6, r1] /* memory barrier */ + +halted: + dsb + wfe /* CPU should be power gated here */ + isb + b halted + +/* + * tegra20_sdram_self_refresh + * + * called with MMU off and caches disabled + * puts sdram in self refresh + * must be executed from IRAM + */ +tegra20_sdram_self_refresh: + mov32 r1, TEGRA_EMC_BASE @ r1 reserved for emc base addr + + mov r2, #3 + str r2, [r1, #EMC_REQ_CTRL] @ stall incoming DRAM requests + +emcidle: + ldr r2, [r1, #EMC_EMC_STATUS] + tst r2, #4 + beq emcidle + + mov r2, #1 + str r2, [r1, #EMC_SELF_REF] + + emc_device_mask r2, r1 + +emcself: + ldr r3, [r1, #EMC_EMC_STATUS] + and r3, r3, r2 + cmp r3, r2 + bne emcself @ loop until DDR in self-refresh + + adr r2, tegra20_sdram_pad_address + adr r3, tegra20_sdram_pad_safe + adr r4, tegra20_sdram_pad_save + mov r5, #0 + + ldr r6, tegra20_sdram_pad_size +padsave: + ldr r0, [r2, r5] @ r0 is the addr in the pad_address + + ldr r1, [r0] + str r1, [r4, r5] @ save the content of the addr + + ldr r1, [r3, r5] + str r1, [r0] @ set the save val to the addr + + add r5, r5, #4 + cmp r6, r5 + bne padsave +padsave_done: + + mov32 r5, TEGRA_CLK_RESET_BASE + ldr r0, [r5, #CLK_RESET_SCLK_BURST] + adr r2, tegra20_sclk_save + str r0, [r2] + dsb + ret lr + +tegra20_sdram_pad_address: + .word TEGRA_APB_MISC_BASE + APB_MISC_XM2CFGCPADCTRL + .word TEGRA_APB_MISC_BASE + APB_MISC_XM2CFGDPADCTRL + .word TEGRA_APB_MISC_BASE + APB_MISC_XM2CLKCFGPADCTRL + .word TEGRA_APB_MISC_BASE + APB_MISC_XM2COMPPADCTRL + .word TEGRA_APB_MISC_BASE + APB_MISC_XM2VTTGENPADCTRL + .word TEGRA_APB_MISC_BASE + APB_MISC_XM2CFGCPADCTRL2 + .word TEGRA_APB_MISC_BASE + APB_MISC_XM2CFGDPADCTRL2 + +tegra20_sdram_pad_size: + .word tegra20_sdram_pad_size - tegra20_sdram_pad_address + +tegra20_sdram_pad_safe: + .word 0x8 + .word 0x8 + .word 0x0 + .word 0x8 + .word 0x5500 + .word 0x08080040 + .word 0x0 + +tegra20_sclk_save: + .word 0x0 + +tegra20_sdram_pad_save: + .rept (tegra20_sdram_pad_size - tegra20_sdram_pad_address) / 4 + .long 0 + .endr + + .ltorg +/* dummy symbol for end of IRAM */ + .align L1_CACHE_SHIFT + .globl tegra20_iram_end +tegra20_iram_end: + b . +#endif |