From 731a9274382f8e6f4961df79fe12ebcc5431a5df Mon Sep 17 00:00:00 2001 From: Joseph Lo Date: Mon, 12 Aug 2013 17:40:05 +0800 Subject: [PATCH] ARM: tegra: add LP1 suspend support for Tegra20 The LP1 suspend mode will power off the CPU, clock gated the PLLs and put SDRAM to self-refresh mode. Any interrupt can wake up device from LP1. The sequence when LP1 suspending: * tunning off L1 data cache and the MMU * putting SDRAM into self-refresh * storing some EMC registers and SCLK burst policy * switching CPU to CLK_M (12MHz OSC) * switching SCLK to CLK_S (32KHz OSC) * tunning off PLLM, PLLP and PLLC * shutting off the CPU rail The sequence of LP1 resuming: * re-enabling PLLM, PLLP, and PLLC * restoring some EMC registers and SCLK burst policy * setting up CCLK burst policy to PLLP * resuming SDRAM to normal mode * jumping to the "tegra_resume" from PMC_SCRATCH41 Due to the SDRAM will be put into self-refresh mode, the low level procedures of LP1 suspending and resuming should be copied to TEGRA_IRAM_CODE_AREA (TEGRA_IRAM_BASE + SZ_4K) when suspending. Before restoring the CPU context when resuming, the SDRAM needs to be switched back to normal mode. And the PLLs need to be re-enabled, SCLK burst policy be restored, CCLK burst policy be set in PLLP. Then jumping to "tegra_resume" that was expected to be stored in PMC_SCRATCH41 to restore CPU context and back to kernel. Based on the work by: Colin Cross Gary King Signed-off-by: Joseph Lo Signed-off-by: Stephen Warren --- arch/arm/mach-tegra/Makefile | 1 + arch/arm/mach-tegra/pm-tegra20.c | 34 ++++ arch/arm/mach-tegra/pm.c | 8 + arch/arm/mach-tegra/pm.h | 2 + arch/arm/mach-tegra/sleep-tegra20.S | 296 ++++++++++++++++++++++++++++ 5 files changed, 341 insertions(+) create mode 100644 arch/arm/mach-tegra/pm-tegra20.c diff --git a/arch/arm/mach-tegra/Makefile b/arch/arm/mach-tegra/Makefile index d341980d5ca9..a3fe22d5b06a 100644 --- a/arch/arm/mach-tegra/Makefile +++ b/arch/arm/mach-tegra/Makefile @@ -17,6 +17,7 @@ obj-$(CONFIG_CPU_IDLE) += cpuidle.o obj-$(CONFIG_ARCH_TEGRA_2x_SOC) += tegra20_speedo.o obj-$(CONFIG_ARCH_TEGRA_2x_SOC) += tegra2_emc.o obj-$(CONFIG_ARCH_TEGRA_2x_SOC) += sleep-tegra20.o +obj-$(CONFIG_ARCH_TEGRA_2x_SOC) += pm-tegra20.o ifeq ($(CONFIG_CPU_IDLE),y) obj-$(CONFIG_ARCH_TEGRA_2x_SOC) += cpuidle-tegra20.o endif diff --git a/arch/arm/mach-tegra/pm-tegra20.c b/arch/arm/mach-tegra/pm-tegra20.c new file mode 100644 index 000000000000..d65e1d786400 --- /dev/null +++ b/arch/arm/mach-tegra/pm-tegra20.c @@ -0,0 +1,34 @@ +/* + * Copyright (c) 2013, NVIDIA Corporation. All rights reserved. + * + * 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 . + */ +#include + +#include "pm.h" + +#ifdef CONFIG_PM_SLEEP +extern u32 tegra20_iram_start, tegra20_iram_end; +extern void tegra20_sleep_core_finish(unsigned long); + +void tegra20_lp1_iram_hook(void) +{ + tegra_lp1_iram.start_addr = &tegra20_iram_start; + tegra_lp1_iram.end_addr = &tegra20_iram_end; +} + +void tegra20_sleep_core_init(void) +{ + tegra_sleep_core_finish = tegra20_sleep_core_finish; +} +#endif diff --git a/arch/arm/mach-tegra/pm.c b/arch/arm/mach-tegra/pm.c index 7739d5586cb7..e718350367e4 100644 --- a/arch/arm/mach-tegra/pm.c +++ b/arch/arm/mach-tegra/pm.c @@ -210,6 +210,10 @@ static int tegra_sleep_core(unsigned long v2p) static bool tegra_lp1_iram_hook(void) { switch (tegra_chip_id) { + case TEGRA20: + if (IS_ENABLED(CONFIG_ARCH_TEGRA_2x_SOC)) + tegra20_lp1_iram_hook(); + break; case TEGRA30: if (IS_ENABLED(CONFIG_ARCH_TEGRA_3x_SOC)) tegra30_lp1_iram_hook(); @@ -232,6 +236,10 @@ static bool tegra_lp1_iram_hook(void) static bool tegra_sleep_core_init(void) { switch (tegra_chip_id) { + case TEGRA20: + if (IS_ENABLED(CONFIG_ARCH_TEGRA_2x_SOC)) + tegra20_sleep_core_init(); + break; case TEGRA30: if (IS_ENABLED(CONFIG_ARCH_TEGRA_3x_SOC)) tegra30_sleep_core_init(); diff --git a/arch/arm/mach-tegra/pm.h b/arch/arm/mach-tegra/pm.h index 803bd5382257..fe204e5256e7 100644 --- a/arch/arm/mach-tegra/pm.h +++ b/arch/arm/mach-tegra/pm.h @@ -30,6 +30,8 @@ struct tegra_lp1_iram { extern struct tegra_lp1_iram tegra_lp1_iram; extern void (*tegra_sleep_core_finish)(unsigned long v2p); +void tegra20_lp1_iram_hook(void); +void tegra20_sleep_core_init(void); void tegra30_lp1_iram_hook(void); void tegra30_sleep_core_init(void); diff --git a/arch/arm/mach-tegra/sleep-tegra20.S b/arch/arm/mach-tegra/sleep-tegra20.S index f87721d6e50d..5c3bd11c9838 100644 --- a/arch/arm/mach-tegra/sleep-tegra20.S +++ b/arch/arm/mach-tegra/sleep-tegra20.S @@ -23,10 +23,49 @@ #include #include #include +#include #include "sleep.h" #include "flowctrl.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) @@ -180,6 +219,28 @@ ENTRY(tegra20_cpu_is_resettable_soon) mov pc, 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) + /* Flush, disable the L1 data cache and exit SMP */ + bl tegra_disable_clean_inv_dcache + + 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_CODE_AREA + add r0, r0, r1 + + mov pc, r3 +ENDPROC(tegra20_sleep_core_finish) + /* * tegra20_sleep_cpu_secondary_finish(unsigned long v2p) * @@ -251,6 +312,150 @@ ENTRY(tegra20_tear_down_cpu) 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_CODE_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] + mov pc, 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] + + mov pc, lr + /* * tegra20_enter_sleep * @@ -275,4 +480,95 @@ halted: 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 + mov pc, 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 -- 2.39.5