diff options
Diffstat (limited to 'arch/arm/mach-imx/lpddr2_freq_imx6q.S')
| -rw-r--r-- | arch/arm/mach-imx/lpddr2_freq_imx6q.S | 765 |
1 files changed, 765 insertions, 0 deletions
diff --git a/arch/arm/mach-imx/lpddr2_freq_imx6q.S b/arch/arm/mach-imx/lpddr2_freq_imx6q.S new file mode 100644 index 000000000000..6c9aac07df16 --- /dev/null +++ b/arch/arm/mach-imx/lpddr2_freq_imx6q.S @@ -0,0 +1,765 @@ +/* + * Copyright (C) 2015-2016 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. + */ + +#include <linux/linkage.h> +#include <asm/smp_scu.h> +#include "hardware.h" + +#define CCM_CBCDR 0x14 +#define CCM_CBCMR 0x18 +#define CCM_CSCMR1 0x1c +#define CCM_CDHIPR 0x48 + +.globl mx6q_lpddr2_freq_change_start +.globl mx6q_lpddr2_freq_change_end + + .macro wait_for_ccm_handshake + /* wait for div update */ +1: + ldr r9, [r2, #CCM_CDHIPR] + cmp r9, #0 + bne 1b + + .endm + + .macro set_mmdc_misc_ralat_2_cycles + + /* Set MMDCx_MISC[RALAT] = 2 cycles */ + ldr r6, [r8, #0x18] + bic r6, r6, #(0x7 << 6) + orr r6, r6, #(0x2 << 6) + str r6, [r8, #0x18] + + /* Check if lpddr2 channel 1 is enabled */ + ldr r6, [r8, #0x18] + ands r6, r6, #(1 << 2) + beq 1f + + ldr r6, [r4, #0x18] + bic r6, r6, #(0x7 << 6) + orr r6, r6, #(0x2 << 6) + str r6, [r4, #0x18] +1: + .endm + + .macro switch_to_400MHz + /* set the MMDC_DIV=1, AXI_DIV=2, AHB_DIV=3 */ + ldr r9, [r2, #CCM_CBCDR] + ldr r6, =0x3f1f00 + bic r9, r9, r6 + orr r9, r9, #(0x9 << 8) + orr r9, r9, #(1 << 16) + str r9, [r2, #CCM_CBCDR] + + wait_for_ccm_handshake + + /* check periph_clk_sel */ + ldr r9, [r2, #CCM_CBCDR] + and r9, r9, #(1 << 25) + cmp r9, #(1 << 25) + bne skip_periph_clk_switch_400m + + /* now switch periph_clk back. */ + ldr r9, [r2, #CCM_CBCDR] + bic r9, r9, #(1 << 25) + str r9, [r2, #CCM_CBCDR] + + wait_for_ccm_handshake + +skip_periph_clk_switch_400m: + + .endm + + .macro switch_to_100MHz + /* set the MMDC_DIV=4, AXI_DIV=8, AHB_DIV=8 */ + ldr r9, [r2, #CCM_CBCDR] + ldr r6, =0x3f1f00 + bic r9, r9, r6 + orr r9, r9, #(0x1F << 16) + orr r9, r9, #(0x1D << 8) + str r9, [r2, #CCM_CBCDR] + + wait_for_ccm_handshake + + /* check if periph_clk_sel is already set. */ + ldr r9, [r2, #CCM_CBCDR] + and r9, r9, #(1 << 25) + cmp r9, #(1 << 25) + bne skip_periph_clk_switch_100m + + /* now switch periph_clk back. */ + ldr r9, [r2, #CCM_CBCDR] + bic r9, r9, #(1 << 25) + str r9, [r2, #CCM_CBCDR] + + wait_for_ccm_handshake + +skip_periph_clk_switch_100m: + + .endm + + .macro switch_to_24MHz + /* + * change the freq now try setting DDR to 24MHz. + * source it from the periph_clk2 ensure the + * periph_clk2 is sourced from 24MHz and the + * divider is 1. + */ + + ldr r9, [r2, #CCM_CBCMR] + bic r9, r9, #(0x3 << 12) + orr r9, r9, #(1 << 12) + str r9, [r2, #CCM_CBCMR] + + ldr r9, [r2, #CCM_CBCDR] + bic r9, r9, #(0x7 << 27) + str r9, [r2, #CCM_CBCDR] + + /* now switch periph_clk to 24MHz. */ + ldr r9, [r2, #CCM_CBCDR] + orr r9, r9, #(1 << 25) + str r9, [r2, #CCM_CBCDR] + + wait_for_ccm_handshake + + /* change all the dividers to 1. */ + ldr r9, [r2, #CCM_CBCDR] + ldr r6, =0x3f1f00 + bic r9, r9, r6 + orr r9, r9, #(1 << 8) + str r9, [r2, #CCM_CBCDR] + + /* Wait for the divider to change. */ + wait_for_ccm_handshake + + .endm + + .macro switch_to_24MHZ_from_pll2 + /* Change DDR freq settings from pll2_pfd2 (div 2) */ + + ldr r9, [r2, #CCM_CBCMR] + bic r9, r9, #(0x3 << 18) + orr r9, r9, #(0x3 << 18) + str r9, [r2, #CCM_CBCMR] + + ldr r9, [r2, #CCM_CBCDR] + bic r9, r9, #(1 << 25) + str r9, [r2, #CCM_CBCDR] + + wait_for_ccm_handshake + + ldr r9, [r2, #CCM_CBCDR] + ldr r6, =0x3f1f00 + bic r9, r9, r6 + orr r9, r9, #(1 << 8) + orr r9, r9, #(0x7 << 19) + str r9, [r2, #CCM_CBCDR] + + wait_for_ccm_handshake + + .endm + + .macro set_timings_below_100MHz_operation + set_mmdc_misc_ralat_2_cycles + + /* Adjust LPDDR2 timings for 24Mhz operation */ + ldr r5, =0x03162073 + str r5, [r8, #0xC] /* MMDC0_MDCFG0 */ + ldr r7, =0x00020482 + str r7, [r8, #0x10] /* MMDC0_MDCFG1 */ + ldr r9, =0x00000049 + str r9, [r8, #0x14] /* MMDC0_MDCFG2 */ + ldr r10, =0x00020333 + str r10, [r8, #0x38] /* MMDC0_MDCFG3LP */ + + /* Check if lpddr2 channel 1 is enabled */ + ldr r6, [r8, #0x18] + ands r6, r6, #(1 << 2) + beq skip_below_100Mhz_ch1_timings + + str r5, [r4, #0xC] /* MMDC1_MDCFG0 */ + str r7, [r4, #0x10] /* MMDC1_MDCFG1 */ + str r9, [r4, #0x14] /* MMDC1_MDCFG2 */ + str r10, [r4, #0x38] /* MMDC1_MDCFG3LP */ + +skip_below_100Mhz_ch1_timings: + + .endm + + .macro restore_mmdc_settings_info + /* restore timing from mmdc_settings_info */ + ldr r6, [r1, #0x0] + ldr r7, [r1, #0x4] +1: + ldr r9, [r7], #0x4 + ldr r10, [r7], #0x4 + str r10, [r8, r9] + subs r6, r6, #0x1 + bne 1b + + /* Check if lpddr2 channel 1 is enabled */ + ldr r6, [r8, #0x18] + ands r6, r6, #(1 << 2) + beq 3f + + ldr r6, [r1, #0x0] + ldr r7, [r1, #0x4] +2: + ldr r9, [r7], #0x4 + ldr r10, [r7], #0x4 + str r10, [r4, r9] + subs r6, r6, #0x1 + bne 2b +3: + + .endm + + .macro mmdc_clk_lower_equal_100MHz + + ldr r10, =100000000 + cmp r0, r10 + beq set_timmings_100MHz + set_timings_below_100MHz_operation + b common_to_lower_equal_100MHz + +set_timmings_100MHz: + restore_mmdc_settings_info + set_mmdc_misc_ralat_2_cycles + +common_to_lower_equal_100MHz: + + /* if MMDC is not in 400MHz mode, skip double mu count */ + ldr r5, [r1, #0x8] + ldr r6, =400000000 + cmp r5, r6 + bne skip_lower_force_measure_ch1 + + /* + * Prior to reducing the DDR frequency (at 528/400 MHz), + * read the Measure unit count bits (MU_UNIT_DEL_NUM) + */ + ldr r5, =0x8B8 + ldr r6, [r8, r5] + /* Original MU unit count */ + mov r6, r6, LSR #16 + ldr r9, =0x3FF + and r6, r6, r9 + /* Original MU unit count * 2 */ + mov r7, r6, LSL #1 + /* + * Bypass the automatic measure unit when below 100 MHz + * by setting the Measure unit bypass enable bit (MU_BYP_EN) + */ + ldr r6, [r8, r5] + orr r6, r6, #0x400 + str r6, [r8, r5] + /* + * Double the measure count value read in step 1 and program it in the + * measurement bypass bits (MU_BYP_VAL) of the MMDC PHY Measure Unit + * Register for the reduced frequency operation below 100 MHz + */ + ldr r6, [r8, r5] + ldr r9, =0x3FF + bic r6, r6, r9 + orr r6, r6, r7 + str r6, [r8, r5] + /* Now perform a Force Measurement. */ + ldr r6, [r8, r5] + orr r6, r6, #0x800 + str r6, [r8, r5] + /* Wait for FRC_MSR to clear. */ +force_measure: + ldr r6, [r8, r5] + and r6, r6, #0x800 + cmp r6, #0x0 + bne force_measure + + /* Check if lpddr2 channel 2 is enabled */ + ldr r6, [r8, #0x18] + ands r6, r6, #(1 << 2) + beq skip_lower_force_measure_ch1 + + ldr r5, =0x8B8 + ldr r6, [r4, r5] + /* Original MU unit count */ + mov r6, r6, LSR #16 + ldr r9, =0x3FF + and r6, r6, r9 + /* Original MU unit count * 2 */ + mov r7, r6, LSL #1 + /* + * Bypass the automatic measure unit when below 100 MHz + * by setting the Measure unit bypass enable bit (MU_BYP_EN) + */ + ldr r6, [r4, r5] + orr r6, r6, #0x400 + str r6, [r4, r5] + /* + * Double the measure count value read in step 1 and program it in the + * measurement bypass bits (MU_BYP_VAL) of the MMDC PHY Measure Unit + * Register for the reduced frequency operation below 100 MHz + */ + ldr r6, [r4, r5] + ldr r9, =0x3FF + bic r6, r6, r9 + orr r6, r6, r7 + str r6, [r4, r5] + /* Now perform a Force Measurement. */ + ldr r6, [r4, r5] + orr r6, r6, #0x800 + str r6, [r4, r5] + /* Wait for FRC_MSR to clear. */ +force_measure_ch1: + ldr r6, [r4, r5] + and r6, r6, #0x800 + cmp r6, #0x0 + bne force_measure_ch1 + +skip_lower_force_measure_ch1: + + .endm + + .macro mmdc_clk_above_100MHz + + restore_mmdc_settings_info + + /* Make sure that the PHY measurement unit is NOT in bypass mode */ + ldr r5, =0x8B8 + ldr r6, [r8, r5] + bic r6, r6, #0x400 + str r6, [r8, r5] + /* Now perform a Force Measurement. */ + ldr r6, [r8, r5] + orr r6, r6, #0x800 + str r6, [r8, r5] + /* Wait for FRC_MSR to clear. */ +force_measure1: + ldr r6, [r8, r5] + and r6, r6, #0x800 + cmp r6, #0x0 + bne force_measure1 + + /* Check if lpddr2 channel 2 is enabled */ + ldr r6, [r8, #0x18] + ands r6, r6, #(1 << 2) + beq skip_above_force_measure_ch1 + + ldr r5, =0x8B8 + ldr r6, [r4, r5] + bic r6, r6, #0x400 + str r6, [r4, r5] + /* Now perform a Force Measurement. */ + ldr r6, [r4, r5] + orr r6, r6, #0x800 + str r6, [r4, r5] + /* Wait for FRC_MSR to clear. */ +force_measure1_ch1: + ldr r6, [r4, r5] + and r6, r6, #0x800 + cmp r6, #0x0 + bne force_measure1_ch1 + +skip_above_force_measure_ch1: + + .endm + + .macro disable_l1_dcache + + /* + * Flush all data from the L1 data cache before disabling + * SCTLR.C bit. + */ + push {r0 - r11, lr} + + ldr r7, =v7_flush_kern_cache_all + mov lr, pc + mov pc, r7 + pop {r0 - r11, lr} + + /* disable d-cache */ + mrc p15, 0, r6, c1, c0, 0 + bic r6, r6, #0x4 + mcr p15, 0, r6, c1, c0, 0 + dsb + isb + + push {r0 - r11, lr} + + ldr r7, =v7_flush_kern_cache_all + mov lr, pc + mov pc, r7 + pop {r0 - r11, lr} + + .endm + +/* + * mx6_lpddr2_freq_change + * + * Make sure DDR is in self-refresh. + * IRQs are already disabled. + * r0 : DDR freq. + * r1 : mmdc_settings_info + */ + .align 3 +ENTRY(mx6q_lpddr2_freq_change) +mx6q_lpddr2_freq_change_start: + push {r2-r10} + + /* + * Need to flush and disable L1 before + * disabling L2, we need data to + * coherent. Flushing L1 pushes + * everyhting to L2. We sync L2 later, but + * it can still have dirty lines. + * While exiting, we need to enable L2 first + * and then L1. + */ + disable_l1_dcache + + /* + * 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 Branch Target Address Cache (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 + +#ifdef CONFIG_CACHE_L2X0 + /* + * Need to make sure the buffers in L2 are drained. + * Performing a sync operation does this. + */ + ldr r7, =IMX_IO_P2V(MX6Q_L2_BASE_ADDR) + + /* Wait for background operations to complete. */ +wait_for_l2_to_idle: + ldr r6, [r7, #0x730] + cmp r6, #0x0 + bne wait_for_l2_to_idle + + mov r6, #0x0 + str r6, [r7, #0x730] + + /* + * The second dsb might be needed to keep cache sync (device write) + * ordering with the memory accesses before it. + */ + dsb + isb + + /* Disable L2. */ + str r6, [r7, #0x100] +#endif + + ldr r3, =IMX_IO_P2V(MX6Q_ANATOP_BASE_ADDR) + ldr r2, =IMX_IO_P2V(MX6Q_CCM_BASE_ADDR) + ldr r8, =IMX_IO_P2V(MX6Q_MMDC_P0_BASE_ADDR) + ldr r4, =IMX_IO_P2V(MX6Q_MMDC_P1_BASE_ADDR) + + /* Disable Automatic power savings. */ + ldr r6, [r8, #0x404] + orr r6, r6, #0x01 + str r6, [r8, #0x404] + + /* MMDC0_MDPDC disable power down timer */ + ldr r6, [r8, #0x4] + bic r6, r6, #0xff00 + str r6, [r8, #0x4] + + /* Check if lpddr2 channel 2 is enabled */ + ldr r6, [r8, #0x18] + ands r6, r6, #(1 << 2) + beq skip_psd_ch1 + + ldr r6, [r4, #0x404] + orr r6, r6, #0x01 + str r6, [r4, #0x404] + + ldr r6, [r4, #0x4] + bic r6, r6, #0xff00 + str r6, [r4, #0x4] + +skip_psd_ch1: + /* Delay for a while */ + ldr r10, =10 +delay1: + ldr r7, =0 +cont1: + ldr r6, [r8, r7] + add r7, r7, #4 + cmp r7, #16 + bne cont1 + sub r10, r10, #1 + cmp r10, #0 + bgt delay1 + + /* 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] + + /* Check if lpddr2 channel 2 is enabled */ + ldr r6, [r8, #0x18] + ands r6, r6, #(1 << 2) + beq skip_sbs_ch1 + + ldr r6, [r4, #0x404] + orr r6, r6, #0x200000 + str r6, [r4, #0x404] + +poll_dvfs_set_2: + ldr r6, [r4, #0x404] + and r6, r6, #0x2000000 + cmp r6, #0x2000000 + bne poll_dvfs_set_2 + + ldr r6, [r4, #0x410] + orr r6, r6, #0x100 + str r6, [r4, #0x410] + +skip_sbs_ch1: + ldr r10, =100000000 + cmp r0, r10 + bgt set_ddr_mu_above_100 + mmdc_clk_lower_equal_100MHz + +set_ddr_mu_above_100: + ldr r10, =24000000 + cmp r0, r10 + beq set_to_24MHz + + ldr r10, =100000000 + cmp r0, r10 + beq set_to_100MHz + + ldr r10, =400000000 + cmp r0, r10 + switch_to_400MHz + b done + +set_to_24MHz: +/* + switch_to_24MHZ_from_pll2 +*/ + switch_to_24MHz + b done + +set_to_100MHz: + switch_to_100MHz + +done: + + ldr r10,=100000000 + cmp r0, r10 + ble skip_mmdc_clk_check + mmdc_clk_above_100MHz + +skip_mmdc_clk_check: + + /* 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] + + /* Check if lpddr2 channel 2 is enabled */ + ldr r6, [r8, #0x18] + ands r6, r6, #(1 << 2) + beq skip_enable_psd_ch1 + + ldr r6, [r4, #0x404] + bic r6, r6, #0x200000 + str r6, [r4, #0x404] + +poll_dvfs_clear_2: + ldr r6, [r4, #0x404] + and r6, r6, #0x2000000 + cmp r6, #0x2000000 + beq poll_dvfs_clear_2 + + ldr r6, [r4, #0x404] + bic r6, r6, #0x01 + str r6, [r4, #0x404] + +skip_enable_psd_ch1: + ldr r10, =24000000 + cmp r0, r10 + beq skip_power_down + + /* Enable MMDC power down timer. */ + ldr r6, [r8, #0x4] + orr r6, r6, #0x5500 + str r6, [r8, #0x4] + + /* Check if lpddr2 channel 2 is enabled */ + ldr r6, [r8, #0x18] + ands r6, r6, #(1 << 2) + beq skip_power_down + + ldr r6, [r4, #0x4] + orr r6, r6, #0x5500 + str r6, [r4, #0x4] + +skip_power_down: + /* clear SBS - unblock DDR accesses */ + ldr r6, [r8, #0x410] + bic r6, r6, #0x100 + str r6, [r8, #0x410] + + /* Check if lpddr2 channel 2 is enabled */ + ldr r6, [r8, #0x18] + ands r6, r6, #(1 << 2) + beq skip_disable_sbs_ch1 + + ldr r6, [r4, #0x410] + bic r6, r6, #0x100 + str r6, [r4, #0x410] + +skip_disable_sbs_ch1: +#ifdef CONFIG_CACHE_L2X0 + /* Enable L2. */ + ldr r7, =IMX_IO_P2V(MX6Q_L2_BASE_ADDR) + ldr r6, =0x1 + str r6, [r7, #0x100] +#endif + + /* 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 + + 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 {r2-r10} + + /* Restore registers */ + mov pc, lr + + /* + * Add ltorg here to ensure that all + * literals are stored here and are + * within the text space. + */ + .ltorg +mx6q_lpddr2_freq_change_end: |