diff options
author | Claudiu Beznea <claudiu.beznea@microchip.com> | 2021-04-15 13:49:53 +0300 |
---|---|---|
committer | Nicolas Ferre <nicolas.ferre@microchip.com> | 2021-07-19 14:32:12 +0200 |
commit | 87e1b30c29b9ae41cfbf6cda42f970b529bfcfb9 (patch) | |
tree | 02058bd4d7fcc4beb6afc6f0353cc397b759f472 /arch/arm/mach-at91 | |
parent | 29cdf077a9ef238e608eb1243cdcc9e47592ad02 (diff) | |
download | linux-87e1b30c29b9ae41cfbf6cda42f970b529bfcfb9.tar.bz2 |
ARM: at91: pm: avoid push and pop on stack while memory is in self-refersh
For the previous AT91 RAM controller and self-refresh procedure this
had no side effects. However, for SAMA7G5 the self-refresh procedure
doesn't allow this anymore as the RAM controller ports are closed
before switching it to self-refresh. This commits prepares the code
for the following ones adding self-refresh and PM support for SAMA7G5.
Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Signed-off-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Link: https://lore.kernel.org/r/20210415105010.569620-8-claudiu.beznea@microchip.com
Diffstat (limited to 'arch/arm/mach-at91')
-rw-r--r-- | arch/arm/mach-at91/pm_suspend.S | 397 |
1 files changed, 205 insertions, 192 deletions
diff --git a/arch/arm/mach-at91/pm_suspend.S b/arch/arm/mach-at91/pm_suspend.S index 3d20c9880fee..960ad29cce51 100644 --- a/arch/arm/mach-at91/pm_suspend.S +++ b/arch/arm/mach-at91/pm_suspend.S @@ -75,98 +75,147 @@ tmp3 .req r6 .arm -/* - * void at91_suspend_sram_fn(struct at91_pm_data*) - * @input param: - * @r0: base address of struct at91_pm_data +/** + * Enable self-refresh + * + * register usage: + * @r1: memory type + * @r2: base address of the sram controller + * @r3: temporary */ -/* at91_pm_suspend_in_sram must be 8-byte aligned per the requirements of fncpy() */ - .align 3 -ENTRY(at91_pm_suspend_in_sram) - /* Save registers on stack */ - stmfd sp!, {r4 - r12, lr} +.macro at91_sramc_self_refresh_ena + ldr r1, .memtype + ldr r2, .sramc_base - /* Drain write buffer */ - mov tmp1, #0 - mcr p15, 0, tmp1, c7, c10, 4 + cmp r1, #AT91_MEMCTRL_MC + bne sr_ena_ddrc_sf - ldr tmp1, [r0, #PM_DATA_PMC] - str tmp1, .pmc_base - ldr tmp1, [r0, #PM_DATA_RAMC0] - str tmp1, .sramc_base - ldr tmp1, [r0, #PM_DATA_RAMC1] - str tmp1, .sramc1_base - ldr tmp1, [r0, #PM_DATA_MEMCTRL] - str tmp1, .memtype - ldr tmp1, [r0, #PM_DATA_MODE] - str tmp1, .pm_mode - ldr tmp1, [r0, #PM_DATA_PMC_MCKR_OFFSET] - str tmp1, .mckr_offset - ldr tmp1, [r0, #PM_DATA_PMC_VERSION] - str tmp1, .pmc_version - /* Both ldrne below are here to preload their address in the TLB */ - ldr tmp1, [r0, #PM_DATA_SHDWC] - str tmp1, .shdwc - cmp tmp1, #0 - ldrne tmp2, [tmp1, #0] - ldr tmp1, [r0, #PM_DATA_SFRBU] - str tmp1, .sfrbu - cmp tmp1, #0 - ldrne tmp2, [tmp1, #0x10] + /* Active SDRAM self-refresh mode */ + mov r3, #1 + str r3, [r2, #AT91_MC_SDRAMC_SRR] + b sr_ena_exit - /* Active the self-refresh mode */ - mov r0, #SRAMC_SELF_FRESH_ACTIVE - bl at91_sramc_self_refresh +sr_ena_ddrc_sf: + cmp r1, #AT91_MEMCTRL_DDRSDR + bne sr_ena_sdramc_sf - ldr r0, .pm_mode - cmp r0, #AT91_PM_STANDBY - beq standby - cmp r0, #AT91_PM_BACKUP - beq backup_mode + /* + * DDR Memory controller + */ - bl at91_ulp_mode - b exit_suspend + /* LPDDR1 --> force DDR2 mode during self-refresh */ + ldr r3, [r2, #AT91_DDRSDRC_MDR] + str r3, .saved_sam9_mdr + bic r3, r3, #~AT91_DDRSDRC_MD + cmp r3, #AT91_DDRSDRC_MD_LOW_POWER_DDR + ldreq r3, [r2, #AT91_DDRSDRC_MDR] + biceq r3, r3, #AT91_DDRSDRC_MD + orreq r3, r3, #AT91_DDRSDRC_MD_DDR2 + streq r3, [r2, #AT91_DDRSDRC_MDR] -standby: - /* Wait for interrupt */ - ldr pmc, .pmc_base - at91_cpu_idle - b exit_suspend + /* Active DDRC self-refresh mode */ + ldr r3, [r2, #AT91_DDRSDRC_LPR] + str r3, .saved_sam9_lpr + bic r3, r3, #AT91_DDRSDRC_LPCB + orr r3, r3, #AT91_DDRSDRC_LPCB_SELF_REFRESH + str r3, [r2, #AT91_DDRSDRC_LPR] -backup_mode: - bl at91_backup_mode - b exit_suspend + /* If using the 2nd ddr controller */ + ldr r2, .sramc1_base + cmp r2, #0 + beq sr_ena_no_2nd_ddrc -exit_suspend: - /* Exit the self-refresh mode */ - mov r0, #SRAMC_SELF_FRESH_EXIT - bl at91_sramc_self_refresh + ldr r3, [r2, #AT91_DDRSDRC_MDR] + str r3, .saved_sam9_mdr1 + bic r3, r3, #~AT91_DDRSDRC_MD + cmp r3, #AT91_DDRSDRC_MD_LOW_POWER_DDR + ldreq r3, [r2, #AT91_DDRSDRC_MDR] + biceq r3, r3, #AT91_DDRSDRC_MD + orreq r3, r3, #AT91_DDRSDRC_MD_DDR2 + streq r3, [r2, #AT91_DDRSDRC_MDR] - /* Restore registers, and return */ - ldmfd sp!, {r4 - r12, pc} -ENDPROC(at91_pm_suspend_in_sram) + /* Active DDRC self-refresh mode */ + ldr r3, [r2, #AT91_DDRSDRC_LPR] + str r3, .saved_sam9_lpr1 + bic r3, r3, #AT91_DDRSDRC_LPCB + orr r3, r3, #AT91_DDRSDRC_LPCB_SELF_REFRESH + str r3, [r2, #AT91_DDRSDRC_LPR] -ENTRY(at91_backup_mode) - /* Switch the master clock source to slow clock. */ - ldr pmc, .pmc_base - ldr tmp2, .mckr_offset - ldr tmp1, [pmc, tmp2] - bic tmp1, tmp1, #AT91_PMC_CSS - str tmp1, [pmc, tmp2] +sr_ena_no_2nd_ddrc: + b sr_ena_exit - wait_mckrdy + /* + * SDRAMC Memory controller + */ +sr_ena_sdramc_sf: + /* Active SDRAMC self-refresh mode */ + ldr r3, [r2, #AT91_SDRAMC_LPR] + str r3, .saved_sam9_lpr + bic r3, r3, #AT91_SDRAMC_LPCB + orr r3, r3, #AT91_SDRAMC_LPCB_SELF_REFRESH + str r3, [r2, #AT91_SDRAMC_LPR] - /*BUMEN*/ - ldr r0, .sfrbu - mov tmp1, #0x1 - str tmp1, [r0, #0x10] + ldr r3, .saved_sam9_lpr + str r3, [r2, #AT91_SDRAMC_LPR] - /* Shutdown */ - ldr r0, .shdwc - mov tmp1, #0xA5000000 - add tmp1, tmp1, #0x1 - str tmp1, [r0, #0] -ENDPROC(at91_backup_mode) +sr_ena_exit: +.endm + +/** + * Disable self-refresh + * + * register usage: + * @r1: memory type + * @r2: base address of the sram controller + * @r3: temporary + */ +.macro at91_sramc_self_refresh_dis + ldr r1, .memtype + ldr r2, .sramc_base + + cmp r1, #AT91_MEMCTRL_MC + bne sr_dis_ddrc_exit_sf + + /* + * at91rm9200 Memory controller + */ + + /* + * For exiting the self-refresh mode, do nothing, + * automatically exit the self-refresh mode. + */ + b sr_dis_exit + +sr_dis_ddrc_exit_sf: + cmp r1, #AT91_MEMCTRL_DDRSDR + bne sdramc_exit_sf + + /* DDR Memory controller */ + + /* Restore MDR in case of LPDDR1 */ + ldr r3, .saved_sam9_mdr + str r3, [r2, #AT91_DDRSDRC_MDR] + /* Restore LPR on AT91 with DDRAM */ + ldr r3, .saved_sam9_lpr + str r3, [r2, #AT91_DDRSDRC_LPR] + + /* If using the 2nd ddr controller */ + ldr r2, .sramc1_base + cmp r2, #0 + ldrne r3, .saved_sam9_mdr1 + strne r3, [r2, #AT91_DDRSDRC_MDR] + ldrne r3, .saved_sam9_lpr1 + strne r3, [r2, #AT91_DDRSDRC_LPR] + + b sr_dis_exit + +sdramc_exit_sf: + /* SDRAMC Memory controller */ + ldr r3, .saved_sam9_lpr + str r3, [r2, #AT91_SDRAMC_LPR] + +sr_dis_exit: +.endm .macro at91_pm_ulp0_mode ldr pmc, .pmc_base @@ -503,7 +552,7 @@ ENDPROC(at91_backup_mode) 2: .endm -ENTRY(at91_ulp_mode) +.macro at91_ulp_mode ldr pmc, .pmc_base ldr tmp2, .mckr_offset ldr tmp3, .pm_mode @@ -552,133 +601,97 @@ ulp_exit: wait_mckrdy - mov pc, lr -ENDPROC(at91_ulp_mode) - -/* - * void at91_sramc_self_refresh(unsigned int is_active) - * - * @input param: - * @r0: 1 - active self-refresh mode - * 0 - exit self-refresh mode - * register usage: - * @r1: memory type - * @r2: base address of the sram controller - */ - -ENTRY(at91_sramc_self_refresh) - ldr r1, .memtype - ldr r2, .sramc_base - - cmp r1, #AT91_MEMCTRL_MC - bne ddrc_sf - - /* - * at91rm9200 Memory controller - */ - - /* - * For exiting the self-refresh mode, do nothing, - * automatically exit the self-refresh mode. - */ - tst r0, #SRAMC_SELF_FRESH_ACTIVE - beq exit_sramc_sf - - /* Active SDRAM self-refresh mode */ - mov r3, #1 - str r3, [r2, #AT91_MC_SDRAMC_SRR] - b exit_sramc_sf - -ddrc_sf: - cmp r1, #AT91_MEMCTRL_DDRSDR - bne sdramc_sf +.endm - /* - * DDR Memory controller - */ - tst r0, #SRAMC_SELF_FRESH_ACTIVE - beq ddrc_exit_sf +.macro at91_backup_mode + /* Switch the master clock source to slow clock. */ + ldr pmc, .pmc_base + ldr tmp2, .mckr_offset + ldr tmp1, [pmc, tmp2] + bic tmp1, tmp1, #AT91_PMC_CSS + str tmp1, [pmc, tmp2] - /* LPDDR1 --> force DDR2 mode during self-refresh */ - ldr r3, [r2, #AT91_DDRSDRC_MDR] - str r3, .saved_sam9_mdr - bic r3, r3, #~AT91_DDRSDRC_MD - cmp r3, #AT91_DDRSDRC_MD_LOW_POWER_DDR - ldreq r3, [r2, #AT91_DDRSDRC_MDR] - biceq r3, r3, #AT91_DDRSDRC_MD - orreq r3, r3, #AT91_DDRSDRC_MD_DDR2 - streq r3, [r2, #AT91_DDRSDRC_MDR] + wait_mckrdy - /* Active DDRC self-refresh mode */ - ldr r3, [r2, #AT91_DDRSDRC_LPR] - str r3, .saved_sam9_lpr - bic r3, r3, #AT91_DDRSDRC_LPCB - orr r3, r3, #AT91_DDRSDRC_LPCB_SELF_REFRESH - str r3, [r2, #AT91_DDRSDRC_LPR] + /*BUMEN*/ + ldr r0, .sfrbu + mov tmp1, #0x1 + str tmp1, [r0, #0x10] - /* If using the 2nd ddr controller */ - ldr r2, .sramc1_base - cmp r2, #0 - beq no_2nd_ddrc + /* Shutdown */ + ldr r0, .shdwc + mov tmp1, #0xA5000000 + add tmp1, tmp1, #0x1 + str tmp1, [r0, #0] +.endm - ldr r3, [r2, #AT91_DDRSDRC_MDR] - str r3, .saved_sam9_mdr1 - bic r3, r3, #~AT91_DDRSDRC_MD - cmp r3, #AT91_DDRSDRC_MD_LOW_POWER_DDR - ldreq r3, [r2, #AT91_DDRSDRC_MDR] - biceq r3, r3, #AT91_DDRSDRC_MD - orreq r3, r3, #AT91_DDRSDRC_MD_DDR2 - streq r3, [r2, #AT91_DDRSDRC_MDR] +/* + * void at91_suspend_sram_fn(struct at91_pm_data*) + * @input param: + * @r0: base address of struct at91_pm_data + */ +/* at91_pm_suspend_in_sram must be 8-byte aligned per the requirements of fncpy() */ + .align 3 +ENTRY(at91_pm_suspend_in_sram) + /* Save registers on stack */ + stmfd sp!, {r4 - r12, lr} - /* Active DDRC self-refresh mode */ - ldr r3, [r2, #AT91_DDRSDRC_LPR] - str r3, .saved_sam9_lpr1 - bic r3, r3, #AT91_DDRSDRC_LPCB - orr r3, r3, #AT91_DDRSDRC_LPCB_SELF_REFRESH - str r3, [r2, #AT91_DDRSDRC_LPR] + /* Drain write buffer */ + mov tmp1, #0 + mcr p15, 0, tmp1, c7, c10, 4 -no_2nd_ddrc: - b exit_sramc_sf + ldr tmp1, [r0, #PM_DATA_PMC] + str tmp1, .pmc_base + ldr tmp1, [r0, #PM_DATA_RAMC0] + str tmp1, .sramc_base + ldr tmp1, [r0, #PM_DATA_RAMC1] + str tmp1, .sramc1_base + ldr tmp1, [r0, #PM_DATA_MEMCTRL] + str tmp1, .memtype + ldr tmp1, [r0, #PM_DATA_MODE] + str tmp1, .pm_mode + ldr tmp1, [r0, #PM_DATA_PMC_MCKR_OFFSET] + str tmp1, .mckr_offset + ldr tmp1, [r0, #PM_DATA_PMC_VERSION] + str tmp1, .pmc_version + /* Both ldrne below are here to preload their address in the TLB */ + ldr tmp1, [r0, #PM_DATA_SHDWC] + str tmp1, .shdwc + cmp tmp1, #0 + ldrne tmp2, [tmp1, #0] + ldr tmp1, [r0, #PM_DATA_SFRBU] + str tmp1, .sfrbu + cmp tmp1, #0 + ldrne tmp2, [tmp1, #0x10] -ddrc_exit_sf: - /* Restore MDR in case of LPDDR1 */ - ldr r3, .saved_sam9_mdr - str r3, [r2, #AT91_DDRSDRC_MDR] - /* Restore LPR on AT91 with DDRAM */ - ldr r3, .saved_sam9_lpr - str r3, [r2, #AT91_DDRSDRC_LPR] + /* Active the self-refresh mode */ + at91_sramc_self_refresh_ena - /* If using the 2nd ddr controller */ - ldr r2, .sramc1_base - cmp r2, #0 - ldrne r3, .saved_sam9_mdr1 - strne r3, [r2, #AT91_DDRSDRC_MDR] - ldrne r3, .saved_sam9_lpr1 - strne r3, [r2, #AT91_DDRSDRC_LPR] + ldr r0, .pm_mode + cmp r0, #AT91_PM_STANDBY + beq standby + cmp r0, #AT91_PM_BACKUP + beq backup_mode - b exit_sramc_sf + at91_ulp_mode + b exit_suspend - /* - * SDRAMC Memory controller - */ -sdramc_sf: - tst r0, #SRAMC_SELF_FRESH_ACTIVE - beq sdramc_exit_sf +standby: + /* Wait for interrupt */ + ldr pmc, .pmc_base + at91_cpu_idle + b exit_suspend - /* Active SDRAMC self-refresh mode */ - ldr r3, [r2, #AT91_SDRAMC_LPR] - str r3, .saved_sam9_lpr - bic r3, r3, #AT91_SDRAMC_LPCB - orr r3, r3, #AT91_SDRAMC_LPCB_SELF_REFRESH - str r3, [r2, #AT91_SDRAMC_LPR] +backup_mode: + at91_backup_mode -sdramc_exit_sf: - ldr r3, .saved_sam9_lpr - str r3, [r2, #AT91_SDRAMC_LPR] +exit_suspend: + /* Exit the self-refresh mode */ + at91_sramc_self_refresh_dis -exit_sramc_sf: - mov pc, lr -ENDPROC(at91_sramc_self_refresh) + /* Restore registers, and return */ + ldmfd sp!, {r4 - r12, pc} +ENDPROC(at91_pm_suspend_in_sram) .pmc_base: .word 0 |