linux/drivers/memory/ti-emif-sram-pm.S
Dave Gerlach 6c110561eb memory: ti-emif-sram: Add ti_emif_run_hw_leveling for DDR3 hardware leveling
In certain situations, such as when returning from low power modes, the
EMIF must re-run hardware leveling to properly restore DDR3 access.

This is accomplished by introducing a new ti-emif-sram-pm call,
ti_emif_run_hw_leveling, to check if DDR3 is in use and if so, trigger
the full write and read leveling processes.

Suggested-by: Brad Griffis <bgriffis@ti.com>
Signed-off-by: Dave Gerlach <d-gerlach@ti.com>
Acked-by: Santosh Shilimkar <ssantosh@kernel.org>
Signed-off-by: Tony Lindgren <tony@atomide.com>
2019-04-09 08:31:51 -07:00

376 lines
11 KiB
ArmAsm

/*
* Low level PM code for TI EMIF
*
* Copyright (C) 2016-2017 Texas Instruments Incorporated - http://www.ti.com/
* Dave Gerlach
*
* 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 version 2.
*
* This program is distributed "as is" WITHOUT ANY WARRANTY of any
* kind, whether express or implied; without even the implied warranty
* of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <generated/ti-emif-asm-offsets.h>
#include <linux/linkage.h>
#include <asm/assembler.h>
#include <asm/memory.h>
#include "emif.h"
#define EMIF_POWER_MGMT_WAIT_SELF_REFRESH_8192_CYCLES 0x00a0
#define EMIF_POWER_MGMT_SR_TIMER_MASK 0x00f0
#define EMIF_POWER_MGMT_SELF_REFRESH_MODE 0x0200
#define EMIF_POWER_MGMT_SELF_REFRESH_MODE_MASK 0x0700
#define EMIF_SDCFG_TYPE_DDR2 0x2 << SDRAM_TYPE_SHIFT
#define EMIF_SDCFG_TYPE_DDR3 0x3 << SDRAM_TYPE_SHIFT
#define EMIF_STATUS_READY 0x4
#define AM43XX_EMIF_PHY_CTRL_REG_COUNT 0x120
#define EMIF_AM437X_REGISTERS 0x1
.arm
.align 3
ENTRY(ti_emif_sram)
/*
* void ti_emif_save_context(void)
*
* Used during suspend to save the context of all required EMIF registers
* to local memory if the EMIF is going to lose context during the sleep
* transition. Operates on the VIRTUAL address of the EMIF.
*/
ENTRY(ti_emif_save_context)
stmfd sp!, {r4 - r11, lr} @ save registers on stack
adr r4, ti_emif_pm_sram_data
ldr r0, [r4, #EMIF_PM_BASE_ADDR_VIRT_OFFSET]
ldr r2, [r4, #EMIF_PM_REGS_VIRT_OFFSET]
/* Save EMIF configuration */
ldr r1, [r0, #EMIF_SDRAM_CONFIG]
str r1, [r2, #EMIF_SDCFG_VAL_OFFSET]
ldr r1, [r0, #EMIF_SDRAM_REFRESH_CONTROL]
str r1, [r2, #EMIF_REF_CTRL_VAL_OFFSET]
ldr r1, [r0, #EMIF_SDRAM_TIMING_1]
str r1, [r2, #EMIF_TIMING1_VAL_OFFSET]
ldr r1, [r0, #EMIF_SDRAM_TIMING_2]
str r1, [r2, #EMIF_TIMING2_VAL_OFFSET]
ldr r1, [r0, #EMIF_SDRAM_TIMING_3]
str r1, [r2, #EMIF_TIMING3_VAL_OFFSET]
ldr r1, [r0, #EMIF_POWER_MANAGEMENT_CONTROL]
str r1, [r2, #EMIF_PMCR_VAL_OFFSET]
ldr r1, [r0, #EMIF_POWER_MANAGEMENT_CTRL_SHDW]
str r1, [r2, #EMIF_PMCR_SHDW_VAL_OFFSET]
ldr r1, [r0, #EMIF_SDRAM_OUTPUT_IMPEDANCE_CALIBRATION_CONFIG]
str r1, [r2, #EMIF_ZQCFG_VAL_OFFSET]
ldr r1, [r0, #EMIF_DDR_PHY_CTRL_1]
str r1, [r2, #EMIF_DDR_PHY_CTLR_1_OFFSET]
ldr r1, [r0, #EMIF_COS_CONFIG]
str r1, [r2, #EMIF_COS_CONFIG_OFFSET]
ldr r1, [r0, #EMIF_PRIORITY_TO_CLASS_OF_SERVICE_MAPPING]
str r1, [r2, #EMIF_PRIORITY_TO_COS_MAPPING_OFFSET]
ldr r1, [r0, #EMIF_CONNECTION_ID_TO_CLASS_OF_SERVICE_1_MAPPING]
str r1, [r2, #EMIF_CONNECT_ID_SERV_1_MAP_OFFSET]
ldr r1, [r0, #EMIF_CONNECTION_ID_TO_CLASS_OF_SERVICE_2_MAPPING]
str r1, [r2, #EMIF_CONNECT_ID_SERV_2_MAP_OFFSET]
ldr r1, [r0, #EMIF_OCP_CONFIG]
str r1, [r2, #EMIF_OCP_CONFIG_VAL_OFFSET]
ldr r5, [r4, #EMIF_PM_CONFIG_OFFSET]
cmp r5, #EMIF_SRAM_AM43_REG_LAYOUT
bne emif_skip_save_extra_regs
ldr r1, [r0, #EMIF_READ_WRITE_LEVELING_RAMP_CONTROL]
str r1, [r2, #EMIF_RD_WR_LEVEL_RAMP_CTRL_OFFSET]
ldr r1, [r0, #EMIF_READ_WRITE_EXECUTION_THRESHOLD]
str r1, [r2, #EMIF_RD_WR_EXEC_THRESH_OFFSET]
ldr r1, [r0, #EMIF_LPDDR2_NVM_TIMING]
str r1, [r2, #EMIF_LPDDR2_NVM_TIM_OFFSET]
ldr r1, [r0, #EMIF_LPDDR2_NVM_TIMING_SHDW]
str r1, [r2, #EMIF_LPDDR2_NVM_TIM_SHDW_OFFSET]
ldr r1, [r0, #EMIF_DLL_CALIB_CTRL]
str r1, [r2, #EMIF_DLL_CALIB_CTRL_VAL_OFFSET]
ldr r1, [r0, #EMIF_DLL_CALIB_CTRL_SHDW]
str r1, [r2, #EMIF_DLL_CALIB_CTRL_VAL_SHDW_OFFSET]
/* Loop and save entire block of emif phy regs */
mov r5, #0x0
add r4, r2, #EMIF_EXT_PHY_CTRL_VALS_OFFSET
add r3, r0, #EMIF_EXT_PHY_CTRL_1
ddr_phy_ctrl_save:
ldr r1, [r3, r5]
str r1, [r4, r5]
add r5, r5, #0x4
cmp r5, #AM43XX_EMIF_PHY_CTRL_REG_COUNT
bne ddr_phy_ctrl_save
emif_skip_save_extra_regs:
ldmfd sp!, {r4 - r11, pc} @ restore regs and return
ENDPROC(ti_emif_save_context)
/*
* void ti_emif_restore_context(void)
*
* Used during resume to restore the context of all required EMIF registers
* from local memory after the EMIF has lost context during a sleep transition.
* Operates on the PHYSICAL address of the EMIF.
*/
ENTRY(ti_emif_restore_context)
adr r4, ti_emif_pm_sram_data
ldr r0, [r4, #EMIF_PM_BASE_ADDR_PHYS_OFFSET]
ldr r2, [r4, #EMIF_PM_REGS_PHYS_OFFSET]
/* Config EMIF Timings */
ldr r1, [r2, #EMIF_DDR_PHY_CTLR_1_OFFSET]
str r1, [r0, #EMIF_DDR_PHY_CTRL_1]
str r1, [r0, #EMIF_DDR_PHY_CTRL_1_SHDW]
ldr r1, [r2, #EMIF_TIMING1_VAL_OFFSET]
str r1, [r0, #EMIF_SDRAM_TIMING_1]
str r1, [r0, #EMIF_SDRAM_TIMING_1_SHDW]
ldr r1, [r2, #EMIF_TIMING2_VAL_OFFSET]
str r1, [r0, #EMIF_SDRAM_TIMING_2]
str r1, [r0, #EMIF_SDRAM_TIMING_2_SHDW]
ldr r1, [r2, #EMIF_TIMING3_VAL_OFFSET]
str r1, [r0, #EMIF_SDRAM_TIMING_3]
str r1, [r0, #EMIF_SDRAM_TIMING_3_SHDW]
ldr r1, [r2, #EMIF_REF_CTRL_VAL_OFFSET]
str r1, [r0, #EMIF_SDRAM_REFRESH_CONTROL]
str r1, [r0, #EMIF_SDRAM_REFRESH_CTRL_SHDW]
ldr r1, [r2, #EMIF_PMCR_VAL_OFFSET]
str r1, [r0, #EMIF_POWER_MANAGEMENT_CONTROL]
ldr r1, [r2, #EMIF_PMCR_SHDW_VAL_OFFSET]
str r1, [r0, #EMIF_POWER_MANAGEMENT_CTRL_SHDW]
ldr r1, [r2, #EMIF_COS_CONFIG_OFFSET]
str r1, [r0, #EMIF_COS_CONFIG]
ldr r1, [r2, #EMIF_PRIORITY_TO_COS_MAPPING_OFFSET]
str r1, [r0, #EMIF_PRIORITY_TO_CLASS_OF_SERVICE_MAPPING]
ldr r1, [r2, #EMIF_CONNECT_ID_SERV_1_MAP_OFFSET]
str r1, [r0, #EMIF_CONNECTION_ID_TO_CLASS_OF_SERVICE_1_MAPPING]
ldr r1, [r2, #EMIF_CONNECT_ID_SERV_2_MAP_OFFSET]
str r1, [r0, #EMIF_CONNECTION_ID_TO_CLASS_OF_SERVICE_2_MAPPING]
ldr r1, [r2, #EMIF_OCP_CONFIG_VAL_OFFSET]
str r1, [r0, #EMIF_OCP_CONFIG]
ldr r5, [r4, #EMIF_PM_CONFIG_OFFSET]
cmp r5, #EMIF_SRAM_AM43_REG_LAYOUT
bne emif_skip_restore_extra_regs
ldr r1, [r2, #EMIF_RD_WR_LEVEL_RAMP_CTRL_OFFSET]
str r1, [r0, #EMIF_READ_WRITE_LEVELING_RAMP_CONTROL]
ldr r1, [r2, #EMIF_RD_WR_EXEC_THRESH_OFFSET]
str r1, [r0, #EMIF_READ_WRITE_EXECUTION_THRESHOLD]
ldr r1, [r2, #EMIF_LPDDR2_NVM_TIM_OFFSET]
str r1, [r0, #EMIF_LPDDR2_NVM_TIMING]
ldr r1, [r2, #EMIF_LPDDR2_NVM_TIM_SHDW_OFFSET]
str r1, [r0, #EMIF_LPDDR2_NVM_TIMING_SHDW]
ldr r1, [r2, #EMIF_DLL_CALIB_CTRL_VAL_OFFSET]
str r1, [r0, #EMIF_DLL_CALIB_CTRL]
ldr r1, [r2, #EMIF_DLL_CALIB_CTRL_VAL_SHDW_OFFSET]
str r1, [r0, #EMIF_DLL_CALIB_CTRL_SHDW]
ldr r1, [r2, #EMIF_ZQCFG_VAL_OFFSET]
str r1, [r0, #EMIF_SDRAM_OUTPUT_IMPEDANCE_CALIBRATION_CONFIG]
/* Loop and restore entire block of emif phy regs */
mov r5, #0x0
/* Load ti_emif_regs_amx3 + EMIF_EXT_PHY_CTRL_VALS_OFFSET for address
* to phy register save space
*/
add r3, r2, #EMIF_EXT_PHY_CTRL_VALS_OFFSET
add r4, r0, #EMIF_EXT_PHY_CTRL_1
ddr_phy_ctrl_restore:
ldr r1, [r3, r5]
str r1, [r4, r5]
add r5, r5, #0x4
cmp r5, #AM43XX_EMIF_PHY_CTRL_REG_COUNT
bne ddr_phy_ctrl_restore
emif_skip_restore_extra_regs:
/*
* Output impedence calib needed only for DDR3
* but since the initial state of this will be
* disabled for DDR2 no harm in restoring the
* old configuration
*/
ldr r1, [r2, #EMIF_ZQCFG_VAL_OFFSET]
str r1, [r0, #EMIF_SDRAM_OUTPUT_IMPEDANCE_CALIBRATION_CONFIG]
/* Write to sdcfg last for DDR2 only */
ldr r1, [r2, #EMIF_SDCFG_VAL_OFFSET]
and r2, r1, #SDRAM_TYPE_MASK
cmp r2, #EMIF_SDCFG_TYPE_DDR2
streq r1, [r0, #EMIF_SDRAM_CONFIG]
mov pc, lr
ENDPROC(ti_emif_restore_context)
/*
* void ti_emif_run_hw_leveling(void)
*
* Used during resume to run hardware leveling again and restore the
* configuration of the EMIF PHY, only for DDR3.
*/
ENTRY(ti_emif_run_hw_leveling)
adr r4, ti_emif_pm_sram_data
ldr r0, [r4, #EMIF_PM_BASE_ADDR_PHYS_OFFSET]
ldr r3, [r0, #EMIF_READ_WRITE_LEVELING_CONTROL]
orr r3, r3, #RDWRLVLFULL_START
ldr r2, [r0, #EMIF_SDRAM_CONFIG]
and r2, r2, #SDRAM_TYPE_MASK
cmp r2, #EMIF_SDCFG_TYPE_DDR3
bne skip_hwlvl
str r3, [r0, #EMIF_READ_WRITE_LEVELING_CONTROL]
/*
* If EMIF registers are touched during initial stage of HW
* leveling sequence there will be an L3 NOC timeout error issued
* as the EMIF will not respond, which is not fatal, but it is
* avoidable. This small wait loop is enough time for this condition
* to clear, even at worst case of CPU running at max speed of 1Ghz.
*/
mov r2, #0x2000
1:
subs r2, r2, #0x1
bne 1b
/* Bit clears when operation is complete */
2: ldr r1, [r0, #EMIF_READ_WRITE_LEVELING_CONTROL]
tst r1, #RDWRLVLFULL_START
bne 2b
skip_hwlvl:
mov pc, lr
ENDPROC(ti_emif_run_hw_leveling)
/*
* void ti_emif_enter_sr(void)
*
* Programs the EMIF to tell the SDRAM to enter into self-refresh
* mode during a sleep transition. Operates on the VIRTUAL address
* of the EMIF.
*/
ENTRY(ti_emif_enter_sr)
stmfd sp!, {r4 - r11, lr} @ save registers on stack
adr r4, ti_emif_pm_sram_data
ldr r0, [r4, #EMIF_PM_BASE_ADDR_VIRT_OFFSET]
ldr r2, [r4, #EMIF_PM_REGS_VIRT_OFFSET]
ldr r1, [r0, #EMIF_POWER_MANAGEMENT_CONTROL]
bic r1, r1, #EMIF_POWER_MGMT_SELF_REFRESH_MODE_MASK
orr r1, r1, #EMIF_POWER_MGMT_SELF_REFRESH_MODE
str r1, [r0, #EMIF_POWER_MANAGEMENT_CONTROL]
ldmfd sp!, {r4 - r11, pc} @ restore regs and return
ENDPROC(ti_emif_enter_sr)
/*
* void ti_emif_exit_sr(void)
*
* Programs the EMIF to tell the SDRAM to exit self-refresh mode
* after a sleep transition. Operates on the PHYSICAL address of
* the EMIF.
*/
ENTRY(ti_emif_exit_sr)
adr r4, ti_emif_pm_sram_data
ldr r0, [r4, #EMIF_PM_BASE_ADDR_PHYS_OFFSET]
ldr r2, [r4, #EMIF_PM_REGS_PHYS_OFFSET]
/*
* Toggle EMIF to exit refresh mode:
* if EMIF lost context, PWR_MGT_CTRL is currently 0, writing disable
* (0x0), wont do diddly squat! so do a toggle from SR(0x2) to disable
* (0x0) here.
* *If* EMIF did not lose context, nothing broken as we write the same
* value(0x2) to reg before we write a disable (0x0).
*/
ldr r1, [r2, #EMIF_PMCR_VAL_OFFSET]
bic r1, r1, #EMIF_POWER_MGMT_SELF_REFRESH_MODE_MASK
orr r1, r1, #EMIF_POWER_MGMT_SELF_REFRESH_MODE
str r1, [r0, #EMIF_POWER_MANAGEMENT_CONTROL]
bic r1, r1, #EMIF_POWER_MGMT_SELF_REFRESH_MODE_MASK
str r1, [r0, #EMIF_POWER_MANAGEMENT_CONTROL]
/* Wait for EMIF to become ready */
1: ldr r1, [r0, #EMIF_STATUS]
tst r1, #EMIF_STATUS_READY
beq 1b
mov pc, lr
ENDPROC(ti_emif_exit_sr)
/*
* void ti_emif_abort_sr(void)
*
* Disables self-refresh after a failed transition to a low-power
* state so the kernel can jump back to DDR and follow abort path.
* Operates on the VIRTUAL address of the EMIF.
*/
ENTRY(ti_emif_abort_sr)
stmfd sp!, {r4 - r11, lr} @ save registers on stack
adr r4, ti_emif_pm_sram_data
ldr r0, [r4, #EMIF_PM_BASE_ADDR_VIRT_OFFSET]
ldr r2, [r4, #EMIF_PM_REGS_VIRT_OFFSET]
ldr r1, [r2, #EMIF_PMCR_VAL_OFFSET]
bic r1, r1, #EMIF_POWER_MGMT_SELF_REFRESH_MODE_MASK
str r1, [r0, #EMIF_POWER_MANAGEMENT_CONTROL]
/* Wait for EMIF to become ready */
1: ldr r1, [r0, #EMIF_STATUS]
tst r1, #EMIF_STATUS_READY
beq 1b
ldmfd sp!, {r4 - r11, pc} @ restore regs and return
ENDPROC(ti_emif_abort_sr)
.align 3
ENTRY(ti_emif_pm_sram_data)
.space EMIF_PM_DATA_SIZE
ENTRY(ti_emif_sram_sz)
.word . - ti_emif_save_context