| /* |
| * Copyright 2014 Freescale Semiconductor, Inc. |
| * |
| * The code contained herein is licensed under the GNU General Public |
| * License. You may obtain a copy of the GNU General Public License |
| * Version 2 or later at the following locations: |
| * |
| * http://www.opensource.org/licenses/gpl-license.html |
| * http://www.gnu.org/copyleft/gpl.html |
| */ |
| |
| #include <linux/linkage.h> |
| #include <asm/hardware/cache-l2x0.h> |
| #include "hardware.h" |
| |
| /* |
| * ==================== low level suspend ==================== |
| * |
| * Better to follow below rules to use ARM registers: |
| * r0: pm_info structure address; |
| * r1 ~ r4: for saving pm_info members; |
| * r5 ~ r10: free registers; |
| * r11: io base address. |
| * |
| * suspend ocram space layout: |
| * ======================== high address ====================== |
| * . |
| * . |
| * . |
| * ^ |
| * ^ |
| * ^ |
| * imx6_suspend code |
| * PM_INFO structure(imx6_cpu_pm_info) |
| * ======================== low address ======================= |
| */ |
| |
| /* |
| * Below offsets are based on struct imx6_cpu_pm_info |
| * which defined in arch/arm/mach-imx/pm-imx6q.c, this |
| * structure contains necessary pm info for low level |
| * suspend related code. |
| */ |
| #define PM_INFO_PBASE_OFFSET 0x0 |
| #define PM_INFO_RESUME_ADDR_OFFSET 0x4 |
| #define PM_INFO_CPU_TYPE_OFFSET 0x8 |
| #define PM_INFO_PM_INFO_SIZE_OFFSET 0xC |
| #define PM_INFO_MX6Q_MMDC_P_OFFSET 0x10 |
| #define PM_INFO_MX6Q_MMDC_V_OFFSET 0x14 |
| #define PM_INFO_MX6Q_SRC_P_OFFSET 0x18 |
| #define PM_INFO_MX6Q_SRC_V_OFFSET 0x1C |
| #define PM_INFO_MX6Q_IOMUXC_P_OFFSET 0x20 |
| #define PM_INFO_MX6Q_IOMUXC_V_OFFSET 0x24 |
| #define PM_INFO_MX6Q_CCM_P_OFFSET 0x28 |
| #define PM_INFO_MX6Q_CCM_V_OFFSET 0x2C |
| #define PM_INFO_MX6Q_GPC_P_OFFSET 0x30 |
| #define PM_INFO_MX6Q_GPC_V_OFFSET 0x34 |
| #define PM_INFO_MX6Q_L2_P_OFFSET 0x38 |
| #define PM_INFO_MX6Q_L2_V_OFFSET 0x3C |
| #define PM_INFO_MMDC_IO_NUM_OFFSET 0x40 |
| #define PM_INFO_MMDC_IO_VAL_OFFSET 0x44 |
| |
| #define MX6Q_SRC_GPR1 0x20 |
| #define MX6Q_SRC_GPR2 0x24 |
| #define MX6Q_MMDC_MAPSR 0x404 |
| #define MX6Q_MMDC_MPDGCTRL0 0x83c |
| #define MX6Q_GPC_IMR1 0x08 |
| #define MX6Q_GPC_IMR2 0x0c |
| #define MX6Q_GPC_IMR3 0x10 |
| #define MX6Q_GPC_IMR4 0x14 |
| #define MX6Q_CCM_CCR 0x0 |
| |
| .align 3 |
| |
| .macro sync_l2_cache |
| |
| /* sync L2 cache to drain L2's buffers to DRAM. */ |
| #ifdef CONFIG_CACHE_L2X0 |
| ldr r11, [r0, #PM_INFO_MX6Q_L2_V_OFFSET] |
| mov r6, #0x0 |
| str r6, [r11, #L2X0_CACHE_SYNC] |
| 1: |
| ldr r6, [r11, #L2X0_CACHE_SYNC] |
| ands r6, r6, #0x1 |
| bne 1b |
| #endif |
| |
| .endm |
| |
| .macro resume_mmdc |
| |
| /* restore MMDC IO */ |
| cmp r5, #0x0 |
| ldreq r11, [r0, #PM_INFO_MX6Q_IOMUXC_V_OFFSET] |
| ldrne r11, [r0, #PM_INFO_MX6Q_IOMUXC_P_OFFSET] |
| |
| ldr r6, [r0, #PM_INFO_MMDC_IO_NUM_OFFSET] |
| ldr r7, =PM_INFO_MMDC_IO_VAL_OFFSET |
| add r7, r7, r0 |
| 1: |
| ldr r8, [r7], #0x4 |
| ldr r9, [r7], #0x4 |
| str r9, [r11, r8] |
| subs r6, r6, #0x1 |
| bne 1b |
| |
| cmp r5, #0x0 |
| ldreq r11, [r0, #PM_INFO_MX6Q_MMDC_V_OFFSET] |
| ldrne r11, [r0, #PM_INFO_MX6Q_MMDC_P_OFFSET] |
| |
| cmp r3, #MXC_CPU_IMX6SL |
| bne 4f |
| |
| /* reset read FIFO, RST_RD_FIFO */ |
| ldr r7, =MX6Q_MMDC_MPDGCTRL0 |
| ldr r6, [r11, r7] |
| orr r6, r6, #(1 << 31) |
| str r6, [r11, r7] |
| 2: |
| ldr r6, [r11, r7] |
| ands r6, r6, #(1 << 31) |
| bne 2b |
| |
| /* reset FIFO a second time */ |
| ldr r6, [r11, r7] |
| orr r6, r6, #(1 << 31) |
| str r6, [r11, r7] |
| 3: |
| ldr r6, [r11, r7] |
| ands r6, r6, #(1 << 31) |
| bne 3b |
| 4: |
| /* let DDR out of self-refresh */ |
| ldr r7, [r11, #MX6Q_MMDC_MAPSR] |
| bic r7, r7, #(1 << 21) |
| str r7, [r11, #MX6Q_MMDC_MAPSR] |
| 5: |
| ldr r7, [r11, #MX6Q_MMDC_MAPSR] |
| ands r7, r7, #(1 << 25) |
| bne 5b |
| |
| /* enable DDR auto power saving */ |
| ldr r7, [r11, #MX6Q_MMDC_MAPSR] |
| bic r7, r7, #0x1 |
| str r7, [r11, #MX6Q_MMDC_MAPSR] |
| |
| .endm |
| |
| ENTRY(imx6_suspend) |
| ldr r1, [r0, #PM_INFO_PBASE_OFFSET] |
| ldr r2, [r0, #PM_INFO_RESUME_ADDR_OFFSET] |
| ldr r3, [r0, #PM_INFO_CPU_TYPE_OFFSET] |
| ldr r4, [r0, #PM_INFO_PM_INFO_SIZE_OFFSET] |
| |
| /* |
| * counting the resume address in iram |
| * to set it in SRC register. |
| */ |
| ldr r6, =imx6_suspend |
| ldr r7, =resume |
| sub r7, r7, r6 |
| add r8, r1, r4 |
| add r9, r8, r7 |
| |
| /* |
| * make sure TLB contain the addr we want, |
| * as we will access them after MMDC IO floated. |
| */ |
| |
| ldr r11, [r0, #PM_INFO_MX6Q_CCM_V_OFFSET] |
| ldr r6, [r11, #0x0] |
| ldr r11, [r0, #PM_INFO_MX6Q_GPC_V_OFFSET] |
| ldr r6, [r11, #0x0] |
| |
| /* use r11 to store the IO address */ |
| ldr r11, [r0, #PM_INFO_MX6Q_SRC_V_OFFSET] |
| /* store physical resume addr and pm_info address. */ |
| str r9, [r11, #MX6Q_SRC_GPR1] |
| str r1, [r11, #MX6Q_SRC_GPR2] |
| |
| /* need to sync L2 cache before DSM. */ |
| sync_l2_cache |
| |
| ldr r11, [r0, #PM_INFO_MX6Q_MMDC_V_OFFSET] |
| /* |
| * put DDR explicitly into self-refresh and |
| * disable automatic power savings. |
| */ |
| ldr r7, [r11, #MX6Q_MMDC_MAPSR] |
| orr r7, r7, #0x1 |
| str r7, [r11, #MX6Q_MMDC_MAPSR] |
| |
| /* make the DDR explicitly enter self-refresh. */ |
| ldr r7, [r11, #MX6Q_MMDC_MAPSR] |
| orr r7, r7, #(1 << 21) |
| str r7, [r11, #MX6Q_MMDC_MAPSR] |
| |
| poll_dvfs_set: |
| ldr r7, [r11, #MX6Q_MMDC_MAPSR] |
| ands r7, r7, #(1 << 25) |
| beq poll_dvfs_set |
| |
| ldr r11, [r0, #PM_INFO_MX6Q_IOMUXC_V_OFFSET] |
| ldr r6, =0x0 |
| ldr r7, [r0, #PM_INFO_MMDC_IO_NUM_OFFSET] |
| ldr r8, =PM_INFO_MMDC_IO_VAL_OFFSET |
| add r8, r8, r0 |
| /* i.MX6SL's last 3 IOs need special setting */ |
| cmp r3, #MXC_CPU_IMX6SL |
| subeq r7, r7, #0x3 |
| set_mmdc_io_lpm: |
| ldr r9, [r8], #0x8 |
| str r6, [r11, r9] |
| subs r7, r7, #0x1 |
| bne set_mmdc_io_lpm |
| |
| cmp r3, #MXC_CPU_IMX6SL |
| bne set_mmdc_io_lpm_done |
| ldr r6, =0x1000 |
| ldr r9, [r8], #0x8 |
| str r6, [r11, r9] |
| ldr r9, [r8], #0x8 |
| str r6, [r11, r9] |
| ldr r6, =0x80000 |
| ldr r9, [r8] |
| str r6, [r11, r9] |
| set_mmdc_io_lpm_done: |
| |
| /* |
| * mask all GPC interrupts before |
| * enabling the RBC counters to |
| * avoid the counter starting too |
| * early if an interupt is already |
| * pending. |
| */ |
| ldr r11, [r0, #PM_INFO_MX6Q_GPC_V_OFFSET] |
| ldr r6, [r11, #MX6Q_GPC_IMR1] |
| ldr r7, [r11, #MX6Q_GPC_IMR2] |
| ldr r8, [r11, #MX6Q_GPC_IMR3] |
| ldr r9, [r11, #MX6Q_GPC_IMR4] |
| |
| ldr r10, =0xffffffff |
| str r10, [r11, #MX6Q_GPC_IMR1] |
| str r10, [r11, #MX6Q_GPC_IMR2] |
| str r10, [r11, #MX6Q_GPC_IMR3] |
| str r10, [r11, #MX6Q_GPC_IMR4] |
| |
| /* |
| * enable the RBC bypass counter here |
| * to hold off the interrupts. RBC counter |
| * = 32 (1ms), Minimum RBC delay should be |
| * 400us for the analog LDOs to power down. |
| */ |
| ldr r11, [r0, #PM_INFO_MX6Q_CCM_V_OFFSET] |
| ldr r10, [r11, #MX6Q_CCM_CCR] |
| bic r10, r10, #(0x3f << 21) |
| orr r10, r10, #(0x20 << 21) |
| str r10, [r11, #MX6Q_CCM_CCR] |
| |
| /* enable the counter. */ |
| ldr r10, [r11, #MX6Q_CCM_CCR] |
| orr r10, r10, #(0x1 << 27) |
| str r10, [r11, #MX6Q_CCM_CCR] |
| |
| /* unmask all the GPC interrupts. */ |
| ldr r11, [r0, #PM_INFO_MX6Q_GPC_V_OFFSET] |
| str r6, [r11, #MX6Q_GPC_IMR1] |
| str r7, [r11, #MX6Q_GPC_IMR2] |
| str r8, [r11, #MX6Q_GPC_IMR3] |
| str r9, [r11, #MX6Q_GPC_IMR4] |
| |
| /* |
| * 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 r6, =2000 |
| rbc_loop: |
| subs r6, r6, #0x1 |
| bne rbc_loop |
| |
| /* Zzz, enter stop mode */ |
| wfi |
| nop |
| nop |
| nop |
| nop |
| |
| /* |
| * run to here means there is pending |
| * wakeup source, system should auto |
| * resume, we need to restore MMDC IO first |
| */ |
| mov r5, #0x0 |
| resume_mmdc |
| |
| /* return to suspend finish */ |
| mov pc, lr |
| |
| resume: |
| /* 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 |
| |
| /* get physical resume address from pm_info. */ |
| ldr lr, [r0, #PM_INFO_RESUME_ADDR_OFFSET] |
| /* clear core0's entry and parameter */ |
| ldr r11, [r0, #PM_INFO_MX6Q_SRC_P_OFFSET] |
| mov r7, #0x0 |
| str r7, [r11, #MX6Q_SRC_GPR1] |
| str r7, [r11, #MX6Q_SRC_GPR2] |
| |
| ldr r3, [r0, #PM_INFO_CPU_TYPE_OFFSET] |
| mov r5, #0x1 |
| resume_mmdc |
| |
| mov pc, lr |
| ENDPROC(imx6_suspend) |