[U-Boot] [PATCH 3/4] imx: mx7: add system suspend/resume support
Anson Huang
Anson.Huang at nxp.com
Mon May 28 06:17:41 UTC 2018
This patch adds system suspend/resume support,
when linux kernel enters deep sleep mode, SoC will go
into below mode:
- CA7 platform goes into STOP mode;
- SoC goes into DSM mode;
- DDR goes into self-refresh mode;
- CPU0/SCU will be powered down.
When wake up event arrives:
- SoC DSM mdoe exits;
- CA7 platform exit STOP mode, SCU/CPU0 power up;
- Invalidate L1 cache;
- DDR exit self-refresh mode;
- Do secure monitor mode related initialization;
- Jump to linux kernel resume entry.
Belwo is the log of 1 iteration of system suspend/resume:
[ 338.824862] PM: suspend entry (deep)
[ 338.828853] PM: Syncing filesystems ... done.
[ 338.834433] Freezing user space processes ... (elapsed 0.001 seconds) done.
[ 338.842939] OOM killer disabled.
[ 338.846182] Freezing remaining freezable tasks ... (elapsed 0.001 seconds) done.
[ 338.869717] PM: suspend devices took 0.010 seconds
[ 338.877846] Disabling non-boot CPUs ...
[ 338.960301] Retrying again to check for CPU kill
[ 338.964953] CPU1 killed.
[ 338.968104] Enabling non-boot CPUs ...
[ 338.973598] CPU1 is up
[ 339.267155] mmc1: queuing unknown CIS tuple 0x80 (2 bytes)
[ 339.275833] mmc1: queuing unknown CIS tuple 0x80 (7 bytes)
[ 339.284158] mmc1: queuing unknown CIS tuple 0x80 (6 bytes)
[ 339.385065] PM: resume devices took 0.400 seconds
[ 339.389836] OOM killer enabled.
[ 339.392986] Restarting tasks ... done.
[ 339.398990] PM: suspend exit
Signed-off-by: Anson Huang <Anson.Huang at nxp.com>
---
arch/arm/mach-imx/mx7/psci-mx7.c | 343 ++++++++++++++++++++++++++++++++++++++-
arch/arm/mach-imx/mx7/psci.S | 200 +++++++++++++++++++++++
2 files changed, 541 insertions(+), 2 deletions(-)
diff --git a/arch/arm/mach-imx/mx7/psci-mx7.c b/arch/arm/mach-imx/mx7/psci-mx7.c
index 6f69fd3..7786b4e 100644
--- a/arch/arm/mach-imx/mx7/psci-mx7.c
+++ b/arch/arm/mach-imx/mx7/psci-mx7.c
@@ -8,16 +8,68 @@
#include <asm/psci.h>
#include <asm/secure.h>
#include <asm/arch/imx-regs.h>
+#include <asm/armv7.h>
+#include <asm/gic.h>
#include <common.h>
#include <fsl_wdog.h>
-#define GPC_CPU_PGC_SW_PDN_REQ 0xfc
+#define GPC_LPCR_A7_BSC 0x0
+#define GPC_LPCR_A7_AD 0x4
+#define GPC_SLPCR 0x14
+#define GPC_PGC_ACK_SEL_A7 0x24
+#define GPC_IMR1_CORE0 0x30
+#define GPC_SLOT0_CFG 0xb0
#define GPC_CPU_PGC_SW_PUP_REQ 0xf0
+#define GPC_CPU_PGC_SW_PDN_REQ 0xfc
+#define GPC_PGC_C0 0x800
#define GPC_PGC_C1 0x840
+#define GPC_PGC_SCU 0x880
+
+#define BM_LPCR_A7_BSC_CPU_CLK_ON_LPM 0x4000
+#define BM_LPCR_A7_BSC_LPM1 0xc
+#define BM_LPCR_A7_BSC_LPM0 0x3
+#define BP_LPCR_A7_BSC_LPM0 0
+#define BM_SLPCR_EN_DSM 0x80000000
+#define BM_SLPCR_RBC_EN 0x40000000
+#define BM_SLPCR_REG_BYPASS_COUNT 0x3f000000
+#define BM_SLPCR_VSTBY 0x4
+#define BM_SLPCR_SBYOS 0x2
+#define BM_SLPCR_BYPASS_PMIC_READY 0x1
+#define BM_LPCR_A7_AD_L2PGE 0x10000
+#define BM_LPCR_A7_AD_EN_C1_PUP 0x800
+#define BM_LPCR_A7_AD_EN_C0_PUP 0x200
+#define BM_LPCR_A7_AD_EN_PLAT_PDN 0x10
+#define BM_LPCR_A7_AD_EN_C1_PDN 0x8
+#define BM_LPCR_A7_AD_EN_C0_PDN 0x2
#define BM_CPU_PGC_SW_PDN_PUP_REQ_CORE1_A7 0x2
-/* below is for i.MX7D */
+#define BM_GPC_PGC_ACK_SEL_A7_PD_DUMMY_ACK 0x8000
+#define BM_GPC_PGC_ACK_SEL_A7_PU_DUMMY_ACK 0x80000000
+
+#define MAX_SLOT_NUMBER 10
+#define A7_LPM_WAIT 0x5
+#define A7_LPM_STOP 0xa
+
+#define BM_SYS_COUNTER_CNTCR_FCR1 0x200
+#define BM_SYS_COUNTER_CNTCR_FCR0 0x100
+
+#define REG_SET 0x4
+#define REG_CLR 0x8
+
+#define ANADIG_ARM_PLL 0x60
+#define ANADIG_DDR_PLL 0x70
+#define ANADIG_SYS_PLL 0xb0
+#define ANADIG_ENET_PLL 0xe0
+#define ANADIG_AUDIO_PLL 0xf0
+#define ANADIG_VIDEO_PLL 0x130
+#define BM_ANATOP_ARM_PLL_OVERRIDE BIT(20)
+#define BM_ANATOP_DDR_PLL_OVERRIDE BIT(19)
+#define BM_ANATOP_SYS_PLL_OVERRIDE (0x1ff << 17)
+#define BM_ANATOP_ENET_PLL_OVERRIDE BIT(13)
+#define BM_ANATOP_AUDIO_PLL_OVERRIDE BIT(24)
+#define BM_ANATOP_VIDEO_PLL_OVERRIDE BIT(24)
+
#define SRC_GPR1_MX7D 0x074
#define SRC_A7RCR0 0x004
#define SRC_A7RCR1 0x008
@@ -34,6 +86,172 @@
#define CCM_ROOT_WDOG 0xbb80
#define CCM_CCGR_WDOG1 0x49c0
+enum imx_gpc_slot {
+ CORE0_A7,
+ CORE1_A7,
+ SCU_A7,
+ FAST_MEGA_MIX,
+ MIPI_PHY,
+ PCIE_PHY,
+ USB_OTG1_PHY,
+ USB_OTG2_PHY,
+ USB_HSIC_PHY,
+ CORE0_M4,
+};
+
+enum mxc_cpu_pwr_mode {
+ RUN,
+ WAIT,
+ STOP,
+};
+
+inline void imx_pll_suspend(void)
+{
+ writel(BM_ANATOP_ARM_PLL_OVERRIDE,
+ ANATOP_BASE_ADDR + ANADIG_ARM_PLL + REG_SET);
+ writel(BM_ANATOP_DDR_PLL_OVERRIDE,
+ ANATOP_BASE_ADDR + ANADIG_DDR_PLL + REG_SET);
+ writel(BM_ANATOP_SYS_PLL_OVERRIDE,
+ ANATOP_BASE_ADDR + ANADIG_SYS_PLL + REG_SET);
+ writel(BM_ANATOP_ENET_PLL_OVERRIDE,
+ ANATOP_BASE_ADDR + ANADIG_ENET_PLL + REG_SET);
+ writel(BM_ANATOP_AUDIO_PLL_OVERRIDE,
+ ANATOP_BASE_ADDR + ANADIG_AUDIO_PLL + REG_SET);
+ writel(BM_ANATOP_VIDEO_PLL_OVERRIDE,
+ ANATOP_BASE_ADDR + ANADIG_VIDEO_PLL + REG_SET);
+}
+
+inline void imx_pll_resume(void)
+{
+ writel(BM_ANATOP_ARM_PLL_OVERRIDE,
+ ANATOP_BASE_ADDR + ANADIG_ARM_PLL + REG_CLR);
+ writel(BM_ANATOP_DDR_PLL_OVERRIDE,
+ ANATOP_BASE_ADDR + ANADIG_DDR_PLL + REG_CLR);
+ writel(BM_ANATOP_SYS_PLL_OVERRIDE,
+ ANATOP_BASE_ADDR + ANADIG_SYS_PLL + REG_CLR);
+ writel(BM_ANATOP_ENET_PLL_OVERRIDE,
+ ANATOP_BASE_ADDR + ANADIG_ENET_PLL + REG_CLR);
+ writel(BM_ANATOP_AUDIO_PLL_OVERRIDE,
+ ANATOP_BASE_ADDR + ANADIG_AUDIO_PLL + REG_CLR);
+ writel(BM_ANATOP_VIDEO_PLL_OVERRIDE,
+ ANATOP_BASE_ADDR + ANADIG_VIDEO_PLL + REG_CLR);
+}
+
+__secure void imx_gpcv2_set_lpm_mode(enum mxc_cpu_pwr_mode mode)
+{
+ u32 val1, val2, val3;
+
+ val1 = readl(GPC_IPS_BASE_ADDR + GPC_LPCR_A7_BSC);
+ val2 = readl(GPC_IPS_BASE_ADDR + GPC_SLPCR);
+
+ /* all cores' LPM settings must be same */
+ val1 &= ~(BM_LPCR_A7_BSC_LPM0 | BM_LPCR_A7_BSC_LPM1);
+ val1 |= BM_LPCR_A7_BSC_CPU_CLK_ON_LPM;
+
+ val2 &= ~(BM_SLPCR_EN_DSM | BM_SLPCR_VSTBY | BM_SLPCR_RBC_EN |
+ BM_SLPCR_SBYOS | BM_SLPCR_BYPASS_PMIC_READY);
+ /*
+ * GPC: When improper low-power sequence is used,
+ * the SoC enters low power mode before the ARM core executes WFI.
+ *
+ * Software workaround:
+ * 1) Software should trigger IRQ #32 (IOMUX) to be always pending
+ * by setting IOMUX_GPR1_IRQ.
+ * 2) Software should then unmask IRQ #32 in GPC before setting GPC
+ * Low-Power mode.
+ * 3) Software should mask IRQ #32 right after GPC Low-Power mode
+ * is set.
+ */
+ switch (mode) {
+ case RUN:
+ val3 = readl(GPC_IPS_BASE_ADDR + GPC_IMR1_CORE0);
+ val3 &= ~0x1;
+ writel(val3, GPC_IPS_BASE_ADDR + GPC_IMR1_CORE0);
+ break;
+ case WAIT:
+ val1 |= A7_LPM_WAIT << BP_LPCR_A7_BSC_LPM0;
+ val1 &= ~BM_LPCR_A7_BSC_CPU_CLK_ON_LPM;
+ val3 = readl(GPC_IPS_BASE_ADDR + GPC_IMR1_CORE0);
+ val3 &= ~0x1;
+ writel(val3, GPC_IPS_BASE_ADDR + GPC_IMR1_CORE0);
+ break;
+ case STOP:
+ val1 |= A7_LPM_STOP << BP_LPCR_A7_BSC_LPM0;
+ val1 &= ~BM_LPCR_A7_BSC_CPU_CLK_ON_LPM;
+ val2 |= BM_SLPCR_EN_DSM;
+ val2 |= BM_SLPCR_SBYOS;
+ val2 |= BM_SLPCR_VSTBY;
+ val2 |= BM_SLPCR_BYPASS_PMIC_READY;
+ val3 = readl(GPC_IPS_BASE_ADDR + GPC_IMR1_CORE0);
+ val3 |= 0x1;
+ writel(val3, GPC_IPS_BASE_ADDR + GPC_IMR1_CORE0);
+ break;
+ default:
+ return;
+ }
+ writel(val1, GPC_IPS_BASE_ADDR + GPC_LPCR_A7_BSC);
+ writel(val2, GPC_IPS_BASE_ADDR + GPC_SLPCR);
+}
+
+__secure void imx_gpcv2_set_plat_power_gate_by_lpm(bool pdn)
+{
+ u32 val = readl(GPC_IPS_BASE_ADDR + GPC_LPCR_A7_AD);
+
+ val &= ~(BM_LPCR_A7_AD_EN_PLAT_PDN | BM_LPCR_A7_AD_L2PGE);
+ if (pdn)
+ val |= BM_LPCR_A7_AD_EN_PLAT_PDN | BM_LPCR_A7_AD_L2PGE;
+
+ writel(val, GPC_IPS_BASE_ADDR + GPC_LPCR_A7_AD);
+}
+
+__secure void imx_gpcv2_set_cpu_power_gate_by_lpm(u32 cpu, bool pdn)
+{
+ u32 val;
+
+ val = readl(GPC_IPS_BASE_ADDR + GPC_LPCR_A7_AD);
+ if (cpu == 0) {
+ if (pdn)
+ val |= BM_LPCR_A7_AD_EN_C0_PDN |
+ BM_LPCR_A7_AD_EN_C0_PUP;
+ else
+ val &= ~(BM_LPCR_A7_AD_EN_C0_PDN |
+ BM_LPCR_A7_AD_EN_C0_PUP);
+ }
+ if (cpu == 1) {
+ if (pdn)
+ val |= BM_LPCR_A7_AD_EN_C1_PDN |
+ BM_LPCR_A7_AD_EN_C1_PUP;
+ else
+ val &= ~(BM_LPCR_A7_AD_EN_C1_PDN |
+ BM_LPCR_A7_AD_EN_C1_PUP);
+ }
+ writel(val, GPC_IPS_BASE_ADDR + GPC_LPCR_A7_AD);
+}
+
+__secure void imx_gpcv2_set_slot_ack(u32 index, enum imx_gpc_slot m_core,
+ bool mode, bool ack)
+{
+ u32 val;
+
+ if (index >= MAX_SLOT_NUMBER)
+ return;
+
+ /* set slot */
+ writel(readl(GPC_IPS_BASE_ADDR + GPC_SLOT0_CFG + index * 4) |
+ ((mode + 1) << (m_core * 2)),
+ GPC_IPS_BASE_ADDR + GPC_SLOT0_CFG + index * 4);
+
+ if (ack) {
+ /* set ack */
+ val = readl(GPC_IPS_BASE_ADDR + GPC_PGC_ACK_SEL_A7);
+ /* clear dummy ack */
+ val &= ~(mode ? BM_GPC_PGC_ACK_SEL_A7_PU_DUMMY_ACK :
+ BM_GPC_PGC_ACK_SEL_A7_PD_DUMMY_ACK);
+ val |= 1 << (m_core + (mode ? 16 : 0));
+ writel(val, GPC_IPS_BASE_ADDR + GPC_PGC_ACK_SEL_A7);
+ }
+}
+
static inline void imx_gpcv2_set_m_core_pgc(bool enable, u32 offset)
{
writel(enable, GPC_IPS_BASE_ADDR + offset);
@@ -129,3 +347,124 @@ __secure void imx_system_off(void)
val |= BP_SNVS_LPCR_DP_EN | BP_SNVS_LPCR_TOP;
writel(val, SNVS_BASE_ADDR + SNVS_LPCR);
}
+
+__secure void imx_system_counter_resume(void)
+{
+ u32 val;
+
+ val = readl(SYSCNT_CTRL_IPS_BASE_ADDR);
+ val &= ~BM_SYS_COUNTER_CNTCR_FCR1;
+ val |= BM_SYS_COUNTER_CNTCR_FCR0;
+ writel(val, SYSCNT_CTRL_IPS_BASE_ADDR);
+}
+
+__secure void imx_system_counter_suspend(void)
+{
+ u32 val;
+
+ val = readl(SYSCNT_CTRL_IPS_BASE_ADDR);
+ val &= ~BM_SYS_COUNTER_CNTCR_FCR0;
+ val |= BM_SYS_COUNTER_CNTCR_FCR1;
+ writel(val, SYSCNT_CTRL_IPS_BASE_ADDR);
+}
+
+__secure void gic_resume(void)
+{
+ u32 itlinesnr, i;
+ u32 gic_dist_addr = GIC400_ARB_BASE_ADDR + GIC_DIST_OFFSET;
+
+ /* enable the GIC distributor */
+ writel(readl(gic_dist_addr + GICD_CTLR) | 0x03,
+ gic_dist_addr + GICD_CTLR);
+
+ /* TYPER[4:0] contains an encoded number of available interrupts */
+ itlinesnr = readl(gic_dist_addr + GICD_TYPER) & 0x1f;
+
+ /* set all bits in the GIC group registers to one to allow access
+ * from non-secure state. The first 32 interrupts are private per
+ * CPU and will be set later when enabling the GIC for each core
+ */
+ for (i = 1; i <= itlinesnr; i++)
+ writel((u32)-1, gic_dist_addr + GICD_IGROUPRn + 4 * i);
+}
+
+__secure void imx_udelay(u32 usec)
+{
+ u32 freq;
+ u64 start, end;
+
+ asm volatile("mrc p15, 0, %0, c14, c0, 0" : "=r" (freq));
+ asm volatile("mrrc p15, 0, %Q0, %R0, c14" : "=r" (start));
+ do {
+ asm volatile("mrrc p15, 0, %Q0, %R0, c14" : "=r" (end));
+ if ((end - start) > usec * (freq / 1000000))
+ break;
+ } while (1);
+}
+
+__secure void imx_system_resume(void)
+{
+ unsigned int i, val, imr[4];
+
+ imx_pll_resume();
+ imx_system_counter_resume();
+ imx_gpcv2_set_lpm_mode(RUN);
+ imx_gpcv2_set_cpu_power_gate_by_lpm(0, false);
+ imx_gpcv2_set_plat_power_gate_by_lpm(false);
+ imx_gpcv2_set_m_core_pgc(false, GPC_PGC_C0);
+ imx_gpcv2_set_m_core_pgc(false, GPC_PGC_SCU);
+
+ /*
+ * need to mask all interrupts in GPC before
+ * operating RBC configurations
+ */
+ for (i = 0; i < 4; i++) {
+ imr[i] = readl(GPC_IPS_BASE_ADDR + GPC_IMR1_CORE0 + i * 4);
+ writel(~0, GPC_IPS_BASE_ADDR + GPC_IMR1_CORE0 + i * 4);
+ }
+
+ /* configure RBC enable bit */
+ val = readl(GPC_IPS_BASE_ADDR + GPC_SLPCR);
+ val &= ~BM_SLPCR_RBC_EN;
+ writel(val, GPC_IPS_BASE_ADDR + GPC_SLPCR);
+
+ /* configure RBC count */
+ val = readl(GPC_IPS_BASE_ADDR + GPC_SLPCR);
+ val &= ~BM_SLPCR_REG_BYPASS_COUNT;
+ writel(val, GPC_IPS_BASE_ADDR + GPC_SLPCR);
+
+ /*
+ * need to delay at least 2 cycles of CKIL(32K)
+ * due to hardware design requirement, which is
+ * ~61us, here we use 65us for safe
+ */
+ imx_udelay(65);
+
+ /* restore GPC interrupt mask settings */
+ for (i = 0; i < 4; i++)
+ writel(imr[i], GPC_IPS_BASE_ADDR + GPC_IMR1_CORE0 + i * 4);
+
+ /* initialize gic distributor */
+ gic_resume();
+ _nonsec_init();
+}
+
+__secure void imx_system_suspend(void)
+{
+ /* overwrite PLL to be controlled by low power mode */
+ imx_pll_suspend();
+ imx_system_counter_suspend();
+ /* set CA7 platform to enter STOP mode */
+ imx_gpcv2_set_lpm_mode(STOP);
+ /* enable core0/scu power down/up with low power mode */
+ imx_gpcv2_set_cpu_power_gate_by_lpm(0, true);
+ imx_gpcv2_set_plat_power_gate_by_lpm(true);
+ /* time slot settings for core0 and scu */
+ imx_gpcv2_set_slot_ack(0, CORE0_A7, false, false);
+ imx_gpcv2_set_slot_ack(1, SCU_A7, false, true);
+ imx_gpcv2_set_slot_ack(5, SCU_A7, true, false);
+ imx_gpcv2_set_slot_ack(6, CORE0_A7, true, true);
+ imx_gpcv2_set_m_core_pgc(true, GPC_PGC_C0);
+ imx_gpcv2_set_m_core_pgc(true, GPC_PGC_SCU);
+ psci_v7_flush_dcache_all();
+}
diff --git a/arch/arm/mach-imx/mx7/psci.S b/arch/arm/mach-imx/mx7/psci.S
index d6d19d5..cbe6781 100644
--- a/arch/arm/mach-imx/mx7/psci.S
+++ b/arch/arm/mach-imx/mx7/psci.S
@@ -10,11 +10,108 @@
#include <asm/armv7.h>
#include <asm/arch-armv7/generictimer.h>
#include <asm/psci.h>
+#include <asm/gic.h>
+
+#define DDRC_STAT 0x4
+#define DDRC_PWRCTL 0x30
+#define DDRC_PSTAT 0x3fc
+
+#define SRC_GPR1 0x74
+#define SRC_GPR2 0x78
.pushsection ._secure.text, "ax"
.arch_extension sec
+.global ddrc_enter_self_refresh
+ddrc_enter_self_refresh:
+ /* let DDR out of self-refresh */
+ ldr r1, =0x0
+ str r1, [r0, #DDRC_PWRCTL]
+
+ /* wait rw port_busy clear */
+ ldr r2, =(0x1 << 16)
+ orr r2, r2, #0x1
+1:
+ ldr r1, [r0, #DDRC_PSTAT]
+ ands r1, r1, r2
+ bne 1b
+
+ /* enter self-refresh bit 5 */
+ ldr r1, =(0x1 << 5)
+ str r1, [r0, #DDRC_PWRCTL]
+
+ /* wait until self-refresh mode entered */
+2:
+ ldr r1, [r0, #DDRC_STAT]
+ and r1, r1, #0x3
+ cmp r1, #0x3
+ bne 2b
+3:
+ ldr r1, [r0, #DDRC_STAT]
+ ands r1, r1, #0x20
+ beq 3b
+
+ /* disable dram clk */
+ ldr r1, [r0, #DDRC_PWRCTL]
+ orr r1, r1, #(1 << 3)
+ str r1, [r0, #DDRC_PWRCTL]
+
+ mov pc, lr
+
+.global ddrc_exit_self_refresh
+ddrc_exit_self_refresh:
+ /* let DDR out of self-refresh */
+ ldr r1, =0x0
+ str r1, [r0, #DDRC_PWRCTL]
+
+ /* wait until self-refresh mode entered */
+1:
+ ldr r1, [r0, #DDRC_STAT]
+ and r1, r1, #0x3
+ cmp r1, #0x3
+ beq 1b
+
+ /* enable auto self-refresh */
+ ldr r1, [r0, #DDRC_PWRCTL]
+ orr r1, r1, #(1 << 0)
+ str r1, [r0, #DDRC_PWRCTL]
+
+ mov pc, lr
+
+.globl v7_invalidate_l1
+v7_invalidate_l1:
+ mov r0, #0
+ mcr p15, 2, r0, c0, c0, 0
+ mrc p15, 1, r0, c0, c0, 0
+
+ movw r1, #0x7fff
+ and r2, r1, r0, lsr #13
+
+ movw r1, #0x3ff
+
+ and r3, r1, r0, lsr #3 @ NumWays - 1
+ add r2, r2, #1 @ NumSets
+
+ and r0, r0, #0x7
+ add r0, r0, #4 @ SetShift
+
+ clz r1, r3 @ WayShift
+ add r4, r3, #1 @ NumWays
+1: sub r2, r2, #1 @ NumSets--
+ mov r3, r4 @ Temp = NumWays
+2: subs r3, r3, #1 @ Temp--
+ mov r5, r3, lsl r1
+ mov r6, r2, lsl r0
+ orr r5, r5, r6 @ Reg = (Temp<<WayShift)|(NumSets<<SetShift)
+ mcr p15, 0, r5, c7, c6, 2
+ bgt 2b
+ cmp r2, #0
+ bgt 1b
+ dsb st
+ isb
+ mov pc, lr
+
.globl psci_cpu_on
psci_cpu_on:
push {r4, r5, lr}
@@ -71,4 +168,107 @@ psci_affinity_info:
out_affinity:
pop {pc}
+.globl psci_system_resume
+psci_system_resume:
+ mov sp, r0
+
+ /* force DDR exit self-refresh */
+ ldr r0, =DDRC_IPS_BASE_ADDR
+ bl ddrc_exit_self_refresh
+
+ /* invalidate L1 I-cache first */
+ mov r6, #0x0
+ mcr p15, 0, r6, c7, c5, 0
+ mcr p15, 0, r6, c7, c5, 6
+ /* enable the Icache and branch prediction */
+ mov r6, #0x1800
+ mcr p15, 0, r6, c1, c0, 0
+ isb
+ bl v7_invalidate_l1
+
+ mov r0, #0
+ bl psci_get_target_pc @ target PC => r0
+ push {r0} @ save cpu_resume since _nonsec_init will clean it
+ bl imx_system_resume
+ pop {r1}
+ /* save cpu0 entry r1 */
+ mov r0, #0
+ mov r2, #0
+ bl psci_save
+
+ ldr lr, =psci_cpu_entry
+ mov pc, lr
+
+.globl psci_system_suspend
+psci_system_suspend:
+ /* save cpu0 entry r1 */
+ mov r0, #0
+ mov r2, #0
+ bl psci_save
+
+ bl imx_system_suspend
+
+ ldr r0, =SRC_BASE_ADDR
+ ldr r1, =psci_system_resume
+ str r1, [r0, #SRC_GPR1]
+ str sp, [r0, #SRC_GPR2]
+
+ /* disable GIC distributor */
+ ldr r0, =GIC400_ARB_BASE_ADDR
+ ldr r1, =0x0
+ ldr r2, =GIC_DIST_OFFSET
+ str r1, [r0, r2]
+
+ /* force DDR into self-refresh */
+ ldr r0, =DDRC_IPS_BASE_ADDR
+ bl ddrc_enter_self_refresh
+
+ ldr r11, =GPC_IPS_BASE_ADDR
+ ldr r4, [r11, #0x30]
+ ldr r5, [r11, #0x34]
+ ldr r6, [r11, #0x38]
+ ldr r7, [r11, #0x3c]
+
+ /*
+ * enable the RBC bypass counter here
+ * to hold off the interrupts. RBC counter
+ * = 8 (240us). With this setting, the latency
+ * from wakeup interrupt to ARM power up
+ * is ~250uS.
+ */
+ ldr r8, [r11, #0x14]
+ bic r8, r8, #(0x3f << 24)
+ orr r8, r8, #(0x8 << 24)
+ str r8, [r11, #0x14]
+
+ /* enable the counter. */
+ ldr r8, [r11, #0x14]
+ orr r8, r8, #(0x1 << 30)
+ str r8, [r11, #0x14]
+
+ /* unmask all the GPC interrupts. */
+ str r4, [r11, #0x30]
+ str r5, [r11, #0x34]
+ str r6, [r11, #0x38]
+ str r7, [r11, #0x3c]
+
+ /*
+ * now delay for a short while (3usec)
+ * ARM is at 1GHz at this point
+ * so a short loop should be enough.
+ * this delay is required to ensure that
+ * the RBC counter can start counting in
+ * case an interrupt is already pending
+ * or in case an interrupt arrives just
+ * as ARM is about to assert DSM_request.
+ */
+ ldr r7, =2000
+rbc_loop:
+ subs r7, r7, #0x1
+ bne rbc_loop
+
+dsm:
+ wfi
+ b dsm
+
.popsection
--
2.7.4
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