diff options
Diffstat (limited to 'arch/arm/mach-mx6/mx6sl_wfi.S')
| -rw-r--r-- | arch/arm/mach-mx6/mx6sl_wfi.S | 727 |
1 files changed, 727 insertions, 0 deletions
diff --git a/arch/arm/mach-mx6/mx6sl_wfi.S b/arch/arm/mach-mx6/mx6sl_wfi.S new file mode 100644 index 00000000..c51fcc77 --- /dev/null +++ b/arch/arm/mach-mx6/mx6sl_wfi.S @@ -0,0 +1,727 @@ +/* + * Copyright (C) 2012-2013 Freescale Semiconductor, Inc. All Rights Reserved. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + + * This program is distributed in the hope that 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, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + */ + +#include <linux/linkage.h> +#include <mach/hardware.h> +/* + * The code size is limited to 1.5K + * as we may need to store this code + * along with the suspend and DDR freq change + * code within 8K of IRAM. + */ + +#define IRAM_WAIT_SIZE MX6SL_WFI_IRAM_CODE_SIZE + +.extern iram_tlb_phys_addr +.extern mx6sl_wfi_iram_base +.extern mx6sl_wfi_iram_phys_addr + + .macro sl_ddr_io_save + + ldr r4, [r1, #0x30c] /* DRAM_DQM0 */ + ldr r5, [r1, #0x310] /* DRAM_DQM1 */ + ldr r6, [r1, #0x314] /* DRAM_DQM2 */ + ldr r7, [r1, #0x318] /* DRAM_DQM3 */ + stmfd r9!, {r4-r7} + + ldr r4, [r1, #0x5c4] /* GPR_B0DS */ + ldr r5, [r1, #0x5cc] /* GPR_B1DS */ + ldr r6, [r1, #0x5d4] /* GPR_B2DS */ + ldr r7, [r1, #0x5d8] /* GPR_B3DS */ + stmfd r9!, {r4-r7} + + ldr r4, [r1, #0x300] /* DRAM_CAS */ + ldr r5, [r1, #0x31c] /* DRAM_RAS */ + ldr r6, [r1, #0x338] /* DRAM_SDCLK_0 */ + ldr r7, [r1, #0x5ac] /* GPR_ADDS*/ + stmfd r9!, {r4-r7} + + ldr r4, [r1, #0x5b0] /* DDRMODE_CTL */ + ldr r5, [r1, #0x5c0] /* DDRMODE */ + ldr r6, [r1, #0x33c] /* DRAM_SODT0*/ + ldr r7, [r1, #0x340] /* DRAM_SODT1*/ + stmfd r9!, {r4-r7} + + ldr r4, [r1, #0x330] /* DRAM_SDCKE0 */ + ldr r5, [r1, #0x334] /* DRAM_SDCKE1 */ + ldr r6, [r1, #0x320] /* DRAM_RESET */ + stmfd r9!, {r4-r6} + + .endm + + .macro sl_ddr_io_restore + + /* r9 points to IRAM stack. + * r1 points to IOMUX base address. + * r8 points to MMDC base address. + */ + ldmea r9!, {r4-r7} + str r4, [r1, #0x30c] /* DRAM_DQM0 */ + str r5, [r1, #0x310] /* DRAM_DQM1 */ + str r6, [r1, #0x314] /* DRAM_DQM2 */ + str r7, [r1, #0x318] /* DRAM_DQM3 */ + + ldmea r9!, {r4-r7} + str r4, [r1, #0x5c4] /* GPR_B0DS */ + str r5, [r1, #0x5cc] /* GPR_B1DS */ + str r6, [r1, #0x5d4] /* GPR_B2DS */ + str r7, [r1, #0x5d8] /* GPR_B3DS */ + + ldmea r9!, {r4-r7} + str r4, [r1, #0x300] /* DRAM_CAS */ + str r5, [r1, #0x31c] /* DRAM_RAS */ + str r6, [r1, #0x338] /* DRAM_SDCLK_0 */ + str r7, [r1, #0x5ac] /* GPR_ADDS*/ + + ldmea r9!, {r4-r7} + str r4, [r1, #0x5b0] /* DDRMODE_CTL */ + str r5, [r1, #0x5c0] /* DDRMODE */ + str r6, [r1, #0x33c] /* DRAM_SODT0*/ + str r7, [r1, #0x340] /* DRAM_SODT1*/ + + ldmea r9!, {r4-r6} + str r4, [r1, #0x330] /* DRAM_SDCKE0 */ + str r5, [r1, #0x334] /* DRAM_SDCKE1 */ + str r6, [r1, #0x320] /* DRAM_RESET */ + + /* Need to reset the FIFO to avoid MMDC lockup + * caused because of floating/changing the + * configuration of many DDR IO pads. + */ + /* reset read FIFO, RST_RD_FIFO */ + ldr r7, =0x83c + ldr r6, [r8, r7] + orr r6, r6, #0x80000000 + str r6, [r8, r7] +fifo_reset1_wait: + ldr r6, [r8, r7] + and r6, r6, #0x80000000 + cmp r6, #0 + bne fifo_reset1_wait + + /* reset FIFO a second time */ + ldr r6, [r8, r7] + orr r6, r6, #0x80000000 + str r6, [r8, r7] +fifo_reset2_wait: + ldr r6, [r8, r7] + and r6, r6, #0x80000000 + cmp r6, #0 + bne fifo_reset2_wait + + .endm + + .macro sl_ddr_io_set_lpm + + mov r4, #0 + str r4, [r1, #0x30c] /* DRAM_DQM0 */ + str r4, [r1, #0x310] /* DRAM_DQM1 */ + str r4, [r1, #0x314] /* DRAM_DQM2 */ + str r4, [r1, #0x318] /* DRAM_DQM3 */ + + str r4, [r1, #0x5c4] /* GPR_B0DS */ + str r4, [r1, #0x5cc] /* GPR_B1DS */ + str r4, [r1, #0x5d4] /* GPR_B2DS */ + str r4, [r1, #0x5d8] /* GPR_B3DS */ + + str r4, [r1, #0x300] /* DRAM_CAS */ + str r4, [r1, #0x31c] /* DRAM_RAS */ + str r4, [r1, #0x338] /* DRAM_SDCLK_0 */ + str r4, [r1, #0x5ac] /* GPR_ADDS*/ + + str r4, [r1, #0x5b0] /* DDRMODE_CTL */ + str r4, [r1, #0x5c0] /* DDRMODE */ + str r4, [r1, #0x33c] /* DRAM_SODT0*/ + str r4, [r1, #0x340] /* DRAM_SODT1*/ + + mov r4, #0x80000 + str r4, [r1, #0x320] /* DRAM_RESET */ + mov r4, #0x1000 + str r4, [r1, #0x330] /* DRAM_SDCKE0 */ + str r4, [r1, #0x334] /* DRAM_SDCKE1 */ + + .endm + + .align 3 +/* + * mx6sl_wait + * + * Idle the processor (eg, wait for interrupt). + * Make sure DDR is in self-refresh. + * IRQs are already disabled. + * r0 : arm_podf before WFI is entered + * r1: WFI IRAMcode base address. + */ +ENTRY(mx6sl_wait) + + push {r4-r12} + +mx6sl_lpm_wfi: + mov r11, r2 + + /* Get the IRAM data storage address. */ + mov r10, r1 + mov r9, r1 /* get suspend_iram_base */ + add r9, r9, #IRAM_WAIT_SIZE /* 1.5K */ + + /* + * To ensure no page table walks occur in DDR, we + * have a another page table stored in IRAM that only + * contains entries pointing to IRAM, AIPS1 and AIPS2. + * We need to set the TTBR1 to the new IRAM TLB. + * Do the following steps: + * 1. Flush the Branch Target Address Cache (BTAC) + * 2. Set TTBR1 to point to IRAM page table. + * 3. Disable page table walks in TTBR0 (PD0 = 1) + * 4. Set TTBR0.N=1, implying 0-2G is translated by TTBR0 + * and 2-4G is translated by TTBR1. + */ + + ldr r6, =iram_tlb_phys_addr + ldr r7, [r6] + + /* Flush the BTAC. */ + ldr r6, =0x0 + mcr p15, 0, r6, c7, c1, 6 + + /* Disable Branch Prediction, Z bit in SCTLR. */ + mrc p15, 0, r6, c1, c0, 0 + bic r6, r6, #0x800 + mcr p15, 0, r6, c1, c0, 0 + + dsb + isb + + /* Store the IRAM table in TTBR1 */ + mcr p15, 0, r7, c2, c0, 1 + + /* Read TTBCR and set PD0=1, N = 1 */ + mrc p15, 0, r6, c2, c0, 2 + orr r6, r6, #0x11 + mcr p15, 0, r6, c2, c0, 2 + + dsb + isb + + /* flush the TLB */ + ldr r6, =0x0 + mcr p15, 0, r6, c8, c3, 0 + + /* Disable L1 data cache. */ + mrc p15, 0, r6, c1, c0, 0 + bic r6, r6, #0x4 + mcr p15, 0, r6, c1, c0, 0 + + dsb + + /* + * Sync L2 and then disable it. + */ + dsb + ldr r1, =L2_BASE_ADDR + add r1, r1, #PERIPBASE_VIRT + ldr r6, =0x0 + str r6, [r1, #0x730] + /* Disable L2. */ + str r6, [r1, #0x100] + dsb + isb + + ldr r1, =MX6Q_IOMUXC_BASE_ADDR + add r1, r1, #PERIPBASE_VIRT + + /* Save the DDR IO state. */ + sl_ddr_io_save + + ldr r3, =ANATOP_BASE_ADDR + add r3, r3, #PERIPBASE_VIRT + ldr r2, =CCM_BASE_ADDR + add r2, r2, #PERIPBASE_VIRT + ldr r8, =MMDC_P0_BASE_ADDR + add r8, r8, #PERIPBASE_VIRT + + /* Disable Automatic power savings. */ + ldr r6, [r8, #0x404] + orr r6, r6, #0x01 + str r6, [r8, #0x404] + + /* Make the DDR explicitly enter self-refresh. */ + ldr r6, [r8, #0x404] + orr r6, r6, #0x200000 + str r6, [r8, #0x404] + +poll_dvfs_set_1: + ldr r6, [r8, #0x404] + and r6, r6, #0x2000000 + cmp r6, #0x2000000 + bne poll_dvfs_set_1 + + /* set SBS step-by-step mode */ + ldr r6, [r8, #0x410] + orr r6, r6, #0x100 + str r6, [r8, #0x410] + + cmp r11, #1 + beq audio_mode + + /* Now set DDR rate to 1MHz. */ + /* DDR is from bypassed PLL2 on periph2_clk2 path. + * Set the periph2_clk2_podf to divide by 8. + */ + ldr r6, [r2, #0x14] + orr r6, r6, #0x07 + str r6, [r2, #0x14] + + /* Now set MMDC PODF to divide by 3. */ + ldr r6, [r2, #0x14] + bic r6, r6, #0x38 + orr r6, r6, #0x10 + str r6, [r2, #0x14] + b mmdc_podf + +audio_mode: + /* MMDC is from PLL2_200M. + * Set the mmdc_podf to div by 8. + */ + ldr r6, [r2, #0x14] + orr r6, r6, #0x38 + str r6, [r2, #0x14] + + /* Loop till podf is accepted. */ +mmdc_podf: + ldr r6, [r2, #0x48] + cmp r6, #0x0 + bne mmdc_podf + + /* Set the DDR IO in LPM state. */ + sl_ddr_io_set_lpm + + cmp r11, #1 + beq do_audio_arm_clk + + /* Check if none of the PLLs are + * locked, except PLL1 which will get + * bypassed below. + * We should not be here if PLL2 is not + * bypassed. + */ + ldr r7, =1 + /* USB1 PLL3 */ + ldr r6, [r3, #0x10] + and r6, r6, #0x80000000 + cmp r6, #0x80000000 + beq no_analog_saving + + /* USB2 PLL7 */ + ldr r6, [r3, #0x20] + and r6, r6, #0x80000000 + cmp r6, #0x80000000 + beq no_analog_saving + + /* Audio PLL4 */ + ldr r6, [r3, #0x70] + and r6, r6, #0x80000000 + cmp r6, #0x80000000 + beq no_analog_saving + + /* Video PLL5 */ + ldr r6, [r3, #0xA0] + and r6, r6, #0x80000000 + cmp r6, #0x80000000 + beq no_analog_saving + + /* ENET PLL8 */ + ldr r6, [r3, #0xE0] + and r6, r6, #0x80000000 + cmp r6, #0x80000000 + beq no_analog_saving + + b cont + +no_analog_saving: + ldr r7, =0 + +cont: + /*Set the AHB to 3MHz. AXI to 3MHz. */ + ldr r9, [r2, #0x14] + mov r6, r9 + orr r6, r6, #0x1c00 + orr r6, r6, #0x70000 + str r6, [r2, #0x14] + + /* Loop till podf is accepted. */ +ahb_podf: + ldr r6, [r2, #0x48] + cmp r6, #0x0 + bne podf_loop + + /* Now set ARM to 24MHz. */ + /* Move ARM to be sourced from STEP_CLK + * after setting STEP_CLK to 24MHz. + */ + ldr r6, [r2, #0xc] + bic r6, r6, #0x100 + str r6, [r2, #0x0c] + /* Now PLL1_SW_CLK to step_clk. */ + ldr r6, [r2, #0x0c] + orr r6, r6, #0x4 + str r6, [r2, #0x0c] + + /* Bypass PLL1 and power it down. */ + ldr r6, =(1 << 16) + orr r6, r6, #0x1000 + str r6, [r3, #0x04] + + /* Set the ARM PODF to divide by 8. */ + /* IPG is at 1.5MHz here, we need ARM to + * run at the 12:5 ratio (WAIT mode issue). + */ + ldr r6, =0x7 + str r6, [r2, #0x10] + + /* Loop till podf is accepted. */ +podf_loop: + ldr r6, [r2, #0x48] + cmp r6, #0x0 + bne podf_loop + + /* Check if we can save some + * in the Analog section. + */ + cmp r7, #0x1 + bne do_wfi + + /* Disable 1p1 brown out. */ + ldr r6, [r3, #0x110] + bic r6, r6, #0x2 + str r6, [r3, #0x110] + + /* Enable the weak 2P5 */ + ldr r6, [r3, #0x130] + orr r6, r6, #0x40000 + str r6, [r3, #0x130] + + /*Disable main 2p5. */ + ldr r6, [r3, #0x130] + bic r6, r6, #0x1 + str r6, [r3, #0x130] + + /* Set the OSC bias current to -37.5% + * to drop the power on VDDHIGH. + */ + ldr r6, [r3, #0x150] + orr r6, r6, #0xC000 + str r6, [r3, #0x150] + + /* Enable low power bandgap */ + ldr r6, [r3, #0x260] + orr r6, r6, #0x20 + str r6, [r3, #0x260] + + /* turn off the bias current + * from the regular bandgap. + */ + ldr r6, [r3, #0x260] + orr r6, r6, #0x80 + str r6, [r3, #0x260] + + /* Clear the REFTOP_SELFBIASOFF, + * self-bias circuit of the band gap. + * Per RM, should be cleared when + * band gap is powered down. + */ + ldr r6, [r3, #0x150] + bic r6, r6, #0x8 + str r6, [r3, #0x150] + + /*Power down the regular bandgap. */ + ldr r6, [r3, #0x150] + orr r6, r6, #0x1 + str r6, [r3, #0x150] + + b do_wfi + +do_audio_arm_clk: + /* + * ARM is from PLL2_PFD2_400M here. + * Switch ARM to bypassed PLL1. + */ + ldr r6, [r2, #0xC] + bic r6, r6, #0x4 + str r6, [r2, #0xC] + + /* + * Set the ARM_PODF to divide by 2 + * as IPG is at 4MHz, we cannot run + * ARM_CLK above 9.6MHz when + * system enters WAIT mode. + */ + ldr r6, =0x2 + str r6, [r2, #0x10] + + /* Loop till podf is accepted. */ +podf_loop_audio: + ldr r6, [r2, #0x48] + cmp r6, #0x0 + bne podf_loop_audio + +do_wfi: + /* Now do WFI. */ + wfi + + /* Set original ARM PODF back. */ + str r0, [r2, #0x10] + + /* Loop till podf is accepted. */ +podf_loop1: + ldr r6, [r2, #0x48] + cmp r6, #0x0 + bne podf_loop1 + + cmp r11, #1 + beq audio_arm_clk_restore + + /* + * Check if powered down + * analog components. + */ + cmp r7, #0x1 + bne skip_analog_restore + + /* Power up the regular bandgap. */ + ldr r6, [r3, #0x150] + bic r6, r6, #0x1 + str r6, [r3, #0x150] + + /* turn on the bias current + * from the regular bandgap. + */ + ldr r6, [r3, #0x260] + bic r6, r6, #0x80 + str r6, [r3, #0x260] + + /* Disable the low power bandgap */ + ldr r6, [r3, #0x260] + bic r6, r6, #0x20 + str r6, [r3, #0x260] + + /* + * Set the OSC bias current to max + * value for normal operation. + */ + ldr r6, [r3, #0x150] + bic r6, r6, #0xC000 + str r6, [r3, #0x150] + + /*Enable main 2p5. */ + ldr r6, [r3, #0x130] + orr r6, r6, #0x1 + str r6, [r3, #0x130] + + /* Ensure the 2P5 is up. */ +loop_2p5: + ldr r6, [r3, #0x130] + and r6, r6, #0x20000 + cmp r6, #0x20000 + bne loop_2p5 + + /* Disable the weak 2P5 */ + ldr r6, [r3, #0x130] + bic r6, r6, #0x40000 + str r6, [r3, #0x130] + + /* Enable 1p1 brown out. */ + ldr r6, [r3, #0x110] + orr r6, r6, #0x2 + str r6, [r3, #0x110] + +skip_analog_restore: + + /* Power up PLL1 and un-bypass it. */ + ldr r6, =(1 << 12) + str r6, [r3, #0x08] + + /* Wait for PLL1 to relock. */ +wait_for_pll_lock: + ldr r6, [r3, #0x0] + and r6, r6, #0x80000000 + cmp r6, #0x80000000 + bne wait_for_pll_lock + + ldr r6, =(1 << 16) + str r6, [r3, #0x08] + + /* Set PLL1_sw_clk back to PLL1. */ + ldr r6, [r2, #0x0c] + bic r6, r6, #0x4 + str r6, [r2, #0xc] + + /* Restore AHB/AXI back. */ + str r9, [r2, #0x14] + + /* Loop till podf is accepted. */ +ahb_podf1: + ldr r6, [r2, #0x48] + cmp r6, #0x0 + bne podf_loop1 + + b wfi_restore + +audio_arm_clk_restore: + /* Move ARM back to PLL2_PFD2_400M */ + ldr r6, [r2, #0xC] + orr r6, r6, #0x4 + str r6, [r2, #0xC] + +wfi_restore: + mov r9, r10 /* get suspend_iram_base */ + add r9, r9, #IRAM_WAIT_SIZE /* 4K */ + + /* Restore the DDR IO before exiting self-refresh. */ + sl_ddr_io_restore + + cmp r11, #1 + beq mmdc_audio_restore + + /* Set MMDC back to 24MHz. */ + /* Set periph2_clk2_podf to divide by 1. */ + /* Now set MMDC PODF to divide by 1. */ + ldr r6, [r2, #0x14] + bic r6, r6, #0x3f + str r6, [r2, #0x14] + + b mmdc_podf1 + +mmdc_audio_restore: + /* Set MMDC back to 100MHz. */ + ldr r6, [r2, #0x14] + bic r6, r6, #0x38 + orr r6, r6, #0x8 + str r6, [r2, $0x14] + +mmdc_podf1: + ldr r6, [r2, #0x48] + cmp r6, #0x0 + bne mmdc_podf1 + + /* clear DVFS - exit from self refresh mode */ + ldr r6, [r8, #0x404] + bic r6, r6, #0x200000 + str r6, [r8, #0x404] + +poll_dvfs_clear_1: + ldr r6, [r8, #0x404] + and r6, r6, #0x2000000 + cmp r6, #0x2000000 + beq poll_dvfs_clear_1 + + /* Enable Automatic power savings. */ + ldr r6, [r8, #0x404] + bic r6, r6, #0x01 + str r6, [r8, #0x404] + + /* clear SBS - unblock DDR accesses */ + ldr r6, [r8, #0x410] + bic r6, r6, #0x100 + str r6, [r8, #0x410] + + /* Enable L2. */ + ldr r1, =L2_BASE_ADDR + add r1, r1, #PERIPBASE_VIRT + ldr r6, =0x1 + str r6, [r1, #0x100] + + /* Enable L1 data cache. */ + mrc p15, 0, r6, c1, c0, 0 + orr r6, r6, #0x4 + mcr p15, 0, r6, c1, c0, 0 + + /* Restore the TTBCR */ + + dsb + isb + /* Read TTBCR and set PD0=0, N = 0 */ + mrc p15, 0, r6, c2, c0, 2 + bic r6, r6, #0x11 + mcr p15, 0, r6, c2, c0, 2 + + dsb + isb + + /* flush the TLB */ + ldr r6, =0x0 + mcr p15, 0, r6, c8, c3, 0 + dsb + isb + + /* Enable Branch Prediction, Z bit in SCTLR. */ + mrc p15, 0, r6, c1, c0, 0 + orr r6, r6, #0x800 + mcr p15, 0, r6, c1, c0, 0 + + /* Flush the Branch Target Address Cache (BTAC) */ + ldr r6, =0x0 + mcr p15, 0, r6, c7, c1, 6 + + + /* Add these nops so that the + * prefetcher will not try to get + * any instructions from DDR. + * The prefetch depth is about 23 + * on A9, so adding 25 nops. + */ + nop + nop + nop + nop + nop + + nop + nop + nop + nop + nop + + nop + nop + nop + nop + nop + + nop + nop + nop + nop + nop + + nop + nop + nop + nop + nop + + pop {r4-r12} + + /* Restore registers */ + mov pc, lr + + .type mx6sl_do_wait, #object +ENTRY(mx6sl_do_wait) + .word mx6sl_wait + .size mx6sl_wait, . - mx6sl_wait + |