diff options
Diffstat (limited to 'arch/arm/mach-omap2/sram34xx.S')
| -rw-r--r-- | arch/arm/mach-omap2/sram34xx.S | 129 |
1 files changed, 67 insertions, 62 deletions
diff --git a/arch/arm/mach-omap2/sram34xx.S b/arch/arm/mach-omap2/sram34xx.S index 2c714613634..c080c82521e 100644 --- a/arch/arm/mach-omap2/sram34xx.S +++ b/arch/arm/mach-omap2/sram34xx.S @@ -40,69 +40,74 @@ /* * Change frequency of core dpll * r0 = sdrc_rfr_ctrl r1 = sdrc_actim_ctrla r2 = sdrc_actim_ctrlb r3 = M2 + * r4 = Unlock SDRC DLL? (1 = yes, 0 = no) -- only unlock DLL for + * SDRC rates < 83MHz */ ENTRY(omap3_sram_configure_core_dpll) stmfd sp!, {r1-r12, lr} @ store regs to stack + ldr r4, [sp, #52] @ pull extra args off the stack + dsb @ flush buffered writes to interconnect cmp r3, #0x2 blne configure_sdrc - cmp r3, #0x2 + cmp r4, #0x1 + bleq unlock_dll blne lock_dll - cmp r3, #0x1 - blne unlock_dll bl sdram_in_selfrefresh @ put the SDRAM in self refresh bl configure_core_dpll bl enable_sdrc - cmp r3, #0x1 - blne wait_dll_unlock - cmp r3, #0x2 + cmp r4, #0x1 + bleq wait_dll_unlock blne wait_dll_lock cmp r3, #0x1 blne configure_sdrc + isb @ prevent speculative exec past here mov r0, #0 @ return value ldmfd sp!, {r1-r12, pc} @ restore regs and return unlock_dll: - ldr r4, omap3_sdrc_dlla_ctrl - ldr r5, [r4] - orr r5, r5, #0x4 - str r5, [r4] + ldr r11, omap3_sdrc_dlla_ctrl + ldr r12, [r11] + orr r12, r12, #0x4 + str r12, [r11] @ (no OCP barrier needed) bx lr lock_dll: - ldr r4, omap3_sdrc_dlla_ctrl - ldr r5, [r4] - bic r5, r5, #0x4 - str r5, [r4] + ldr r11, omap3_sdrc_dlla_ctrl + ldr r12, [r11] + bic r12, r12, #0x4 + str r12, [r11] @ (no OCP barrier needed) bx lr sdram_in_selfrefresh: - mov r5, #0x0 @ Move 0 to R5 - mcr p15, 0, r5, c7, c10, 5 @ memory barrier - ldr r4, omap3_sdrc_power @ read the SDRC_POWER register - ldr r5, [r4] @ read the contents of SDRC_POWER - orr r5, r5, #0x40 @ enable self refresh on idle req - str r5, [r4] @ write back to SDRC_POWER register - ldr r4, omap3_cm_iclken1_core @ read the CM_ICLKEN1_CORE reg - ldr r5, [r4] - bic r5, r5, #0x2 @ disable iclk bit for SRDC - str r5, [r4] + ldr r11, omap3_sdrc_power @ read the SDRC_POWER register + ldr r12, [r11] @ read the contents of SDRC_POWER + mov r9, r12 @ keep a copy of SDRC_POWER bits + orr r12, r12, #0x40 @ enable self refresh on idle req + bic r12, r12, #0x4 @ clear PWDENA + str r12, [r11] @ write back to SDRC_POWER register + ldr r12, [r11] @ posted-write barrier for SDRC + ldr r11, omap3_cm_iclken1_core @ read the CM_ICLKEN1_CORE reg + ldr r12, [r11] + bic r12, r12, #0x2 @ disable iclk bit for SDRC + str r12, [r11] wait_sdrc_idle: - ldr r4, omap3_cm_idlest1_core - ldr r5, [r4] - and r5, r5, #0x2 @ check for SDRC idle - cmp r5, #2 + ldr r11, omap3_cm_idlest1_core + ldr r12, [r11] + and r12, r12, #0x2 @ check for SDRC idle + cmp r12, #2 bne wait_sdrc_idle bx lr configure_core_dpll: - ldr r4, omap3_cm_clksel1_pll - ldr r5, [r4] - ldr r6, core_m2_mask_val @ modify m2 for core dpll - and r5, r5, r6 - orr r5, r5, r3, lsl #0x1B @ r3 contains the M2 val - str r5, [r4] - mov r5, #0x800 @ wait for the clock to stabilise + ldr r11, omap3_cm_clksel1_pll + ldr r12, [r11] + ldr r10, core_m2_mask_val @ modify m2 for core dpll + and r12, r12, r10 + orr r12, r12, r3, lsl #0x1B @ r3 contains the M2 val + str r12, [r11] + ldr r12, [r11] @ posted-write barrier for CM + mov r12, #0x800 @ wait for the clock to stabilise cmp r3, #2 bne wait_clk_stable bx lr wait_clk_stable: - subs r5, r5, #1 + subs r12, r12, #1 bne wait_clk_stable nop nop @@ -116,42 +121,42 @@ wait_clk_stable: nop bx lr enable_sdrc: - ldr r4, omap3_cm_iclken1_core - ldr r5, [r4] - orr r5, r5, #0x2 @ enable iclk bit for SDRC - str r5, [r4] + ldr r11, omap3_cm_iclken1_core + ldr r12, [r11] + orr r12, r12, #0x2 @ enable iclk bit for SDRC + str r12, [r11] wait_sdrc_idle1: - ldr r4, omap3_cm_idlest1_core - ldr r5, [r4] - and r5, r5, #0x2 - cmp r5, #0 + ldr r11, omap3_cm_idlest1_core + ldr r12, [r11] + and r12, r12, #0x2 + cmp r12, #0 bne wait_sdrc_idle1 - ldr r4, omap3_sdrc_power - ldr r5, [r4] - bic r5, r5, #0x40 - str r5, [r4] +restore_sdrc_power_val: + ldr r11, omap3_sdrc_power + str r9, [r11] @ restore SDRC_POWER, no barrier needed bx lr wait_dll_lock: - ldr r4, omap3_sdrc_dlla_status - ldr r5, [r4] - and r5, r5, #0x4 - cmp r5, #0x4 + ldr r11, omap3_sdrc_dlla_status + ldr r12, [r11] + and r12, r12, #0x4 + cmp r12, #0x4 bne wait_dll_lock bx lr wait_dll_unlock: - ldr r4, omap3_sdrc_dlla_status - ldr r5, [r4] - and r5, r5, #0x4 - cmp r5, #0x0 + ldr r11, omap3_sdrc_dlla_status + ldr r12, [r11] + and r12, r12, #0x4 + cmp r12, #0x0 bne wait_dll_unlock bx lr configure_sdrc: - ldr r4, omap3_sdrc_rfr_ctrl - str r0, [r4] - ldr r4, omap3_sdrc_actim_ctrla - str r1, [r4] - ldr r4, omap3_sdrc_actim_ctrlb - str r2, [r4] + ldr r11, omap3_sdrc_rfr_ctrl + str r0, [r11] + ldr r11, omap3_sdrc_actim_ctrla + str r1, [r11] + ldr r11, omap3_sdrc_actim_ctrlb + str r2, [r11] + ldr r2, [r11] @ posted-write barrier for SDRC bx lr omap3_sdrc_power: |