Initial import

1 files changed, 580 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..e6b684e14
--- /dev/null
+++ b/arch/arm/mach-tegra/sleep-tegra20.S
@@ -0,0 +1,580 @@
+/*
+ * 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 <asm/assembler.h>
+#include <asm/proc-fns.h>
+#include <asm/cp15.h>
+#include <asm/cache.h>
+
+#include "irammap.h"
+#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)
+ *
+ * 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)
+	/* 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_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