/* * linux/arch/arm/mach-omap2/sram242x.S * * Omap2 specific functions that need to be run in internal SRAM * * (C) Copyright 2004 * Texas Instruments, * Richard Woodruff * * 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., 59 Temple Place, Suite 330, Boston, * MA 02111-1307 USA * * Richard Woodruff notes that any changes to this code must be carefully * audited and tested to ensure that they don't cause a TLB miss while * the SDRAM is inaccessible. Such a situation will crash the system * since it will cause the ARM MMU to attempt to walk the page tables. * These crashes may be intermittent. */ #include #include #include #include #include "prm2xxx_3xxx.h" #include "cm2xxx_3xxx.h" #include "sdrc.h" .text .align 3 ENTRY(omap242x_sram_ddr_init) stmfd sp!, {r0 - r12, lr} @ save registers on stack mov r12, r2 @ capture CS1 vs CS0 mov r8, r3 @ capture force parameter /* frequency shift down */ ldr r2, omap242x_sdi_cm_clksel2_pll @ get address of dpllout reg mov r3, #0x1 @ value for 1x operation str r3, [r2] @ go to L1-freq operation /* voltage shift down */ mov r9, #0x1 @ set up for L1 voltage call bl voltage_shift @ go drop voltage /* dll lock mode */ ldr r11, omap242x_sdi_sdrc_dlla_ctrl @ addr of dlla ctrl ldr r10, [r11] @ get current val cmp r12, #0x1 @ cs1 base (2422 es2.05/1) addeq r11, r11, #0x8 @ if cs1 base, move to DLLB mvn r9, #0x4 @ mask to get clear bit2 and r10, r10, r9 @ clear bit2 for lock mode. orr r10, r10, #0x8 @ make sure DLL on (es2 bit pos) orr r10, r10, #0x2 @ 90 degree phase for all below 133Mhz str r10, [r11] @ commit to DLLA_CTRL bl i_dll_wait @ wait for dll to lock /* get dll value */ add r11, r11, #0x4 @ get addr of status reg ldr r10, [r11] @ get locked value /* voltage shift up */ mov r9, #0x0 @ shift back to L0-voltage bl voltage_shift @ go raise voltage /* frequency shift up */ mov r3, #0x2 @ value for 2x operation str r3, [r2] @ go to L0-freq operation /* reset entry mode for dllctrl */ sub r11, r11, #0x4 @ move from status to ctrl cmp r12, #0x1 @ normalize if cs1 based subeq r11, r11, #0x8 @ possibly back to DLLA cmp r8, #0x1 @ if forced unlock exit orreq r1, r1, #0x4 @ make sure exit with unlocked value str r1, [r11] @ restore DLLA_CTRL high value add r11, r11, #0x8 @ move to DLLB_CTRL addr str r1, [r11] @ set value DLLB_CTRL bl i_dll_wait @ wait for possible lock /* set up for return, DDR should be good */ str r10, [r0] @ write dll_status and return counter ldmfd sp!, {r0 - r12, pc} @ restore regs and return /* ensure the DLL has relocked */ i_dll_wait: mov r4, #0x800 @ delay DLL relock, min 0x400 L3 clocks i_dll_delay: subs r4, r4, #0x1 bne i_dll_delay mov pc, lr /* * shift up or down voltage, use R9 as input to tell level. * wait for it to finish, use 32k sync counter, 1tick=31uS. */ voltage_shift: ldr r4, omap242x_sdi_prcm_voltctrl @ get addr of volt ctrl. ldr r5, [r4] @ get value. ldr r6, prcm_mask_val @ get value of mask and r5, r5, r6 @ apply mask to clear bits orr r5, r5, r9 @ bulld value for L0/L1-volt operation. str r5, [r4] @ set up for change. mov r3, #0x4000 @ get val for force orr r5, r5, r3 @ build value for force str r5, [r4] @ Force transition to L1 ldr r3, omap242x_sdi_timer_32ksynct_cr @ get addr of counter ldr r5, [r3] @ get value add r5, r5, #0x3 @ give it at most 93uS volt_delay: ldr r7, [r3] @ get timer value cmp r5, r7 @ time up? bhi volt_delay @ not yet->branch mov pc, lr @ back to caller. omap242x_sdi_cm_clksel2_pll: .word OMAP2420_CM_REGADDR(PLL_MOD, CM_CLKSEL2) omap242x_sdi_sdrc_dlla_ctrl: .word OMAP242X_SDRC_REGADDR(SDRC_DLLA_CTRL) omap242x_sdi_prcm_voltctrl: .word OMAP2420_PRCM_VOLTCTRL prcm_mask_val: .word 0xFFFF3FFC omap242x_sdi_timer_32ksynct_cr: .word OMAP2_L4_IO_ADDRESS(OMAP2420_32KSYNCT_BASE + 0x010) ENTRY(omap242x_sram_ddr_init_sz) .word . - omap242x_sram_ddr_init /* * Reprograms memory timings. * r0 = [PRCM_FULL | PRCM_HALF] r1 = SDRC_DLLA_CTRL value r2 = [DDR | SDR] * PRCM_FULL = 2, PRCM_HALF = 1, DDR = 1, SDR = 0 */ .align 3 ENTRY(omap242x_sram_reprogram_sdrc) stmfd sp!, {r0 - r10, lr} @ save registers on stack mov r3, #0x0 @ clear for mrc call mcr p15, 0, r3, c7, c10, 4 @ memory barrier, finish ARM SDR/DDR nop nop ldr r6, omap242x_srs_sdrc_rfr_ctrl @ get addr of refresh reg ldr r5, [r6] @ get value mov r5, r5, lsr #8 @ isolate rfr field and drop burst cmp r0, #0x1 @ going to half speed? movne r9, #0x0 @ if up set flag up for pre up, hi volt blne voltage_shift_c @ adjust voltage cmp r0, #0x1 @ going to half speed (post branch link) moveq r5, r5, lsr #1 @ divide by 2 if to half movne r5, r5, lsl #1 @ mult by 2 if to full mov r5, r5, lsl #8 @ put rfr field back into place add r5, r5, #0x1 @ turn on burst of 1 ldr r4, omap242x_srs_cm_clksel2_pll @ get address of out reg ldr r3, [r4] @ get curr value orr r3, r3, #0x3 bic r3, r3, #0x3 @ clear lower bits orr r3, r3, r0 @ new state value str r3, [r4] @ set new state (pll/x, x=1 or 2) nop nop moveq r9, #0x1 @ if speed down, post down, drop volt bleq voltage_shift_c mcr p15, 0, r3, c7, c10, 4 @ memory barrier str r5, [r6] @ set new RFR_1 value add r6, r6, #0x30 @ get RFR_2 addr str r5, [r6] @ set RFR_2 nop cmp r2, #0x1 @ (SDR or DDR) do we need to adjust DLL bne freq_out @ leave if SDR, no DLL function /* With DDR, we need to take care of the DLL for the frequency change */ ldr r2, omap242x_srs_sdrc_dlla_ctrl @ addr of dlla ctrl str r1, [r2] @ write out new SDRC_DLLA_CTRL add r2, r2, #0x8 @ addr to SDRC_DLLB_CTRL str r1, [r2] @ commit to SDRC_DLLB_CTRL mov r1, #0x2000 @ wait DLL relock, min 0x400 L3 clocks dll_wait: subs r1, r1, #0x1 bne dll_wait freq_out: ldmfd sp!, {r0 - r10, pc} @ restore regs and return /* * shift up or down voltage, use R9 as input to tell level. * wait for it to finish, use 32k sync counter, 1tick=31uS. */ voltage_shift_c: ldr r10, omap242x_srs_prcm_voltctrl @ get addr of volt ctrl ldr r8, [r10] @ get value ldr r7, ddr_prcm_mask_val @ get value of mask and r8, r8, r7 @ apply mask to clear bits orr r8, r8, r9 @ bulld value for L0/L1-volt operation. str r8, [r10] @ set up for change. mov r7, #0x4000 @ get val for force orr r8, r8, r7 @ build value for force str r8, [r10] @ Force transition to L1 ldr r10, omap242x_srs_timer_32ksynct @ get addr of counter ldr r8, [r10] @ get value add r8, r8, #0x2 @ give it at most 62uS (min 31+) volt_delay_c: ldr r7, [r10] @ get timer value cmp r8, r7 @ time up? bhi volt_delay_c @ not yet->branch mov pc, lr @ back to caller omap242x_srs_cm_clksel2_pll: .word OMAP2420_CM_REGADDR(PLL_MOD, CM_CLKSEL2) omap242x_srs_sdrc_dlla_ctrl: .word OMAP242X_SDRC_REGADDR(SDRC_DLLA_CTRL) omap242x_srs_sdrc_rfr_ctrl: .word OMAP242X_SDRC_REGADDR(SDRC_RFR_CTRL_0) omap242x_srs_prcm_voltctrl: .word OMAP2420_PRCM_VOLTCTRL ddr_prcm_mask_val: .word 0xFFFF3FFC omap242x_srs_timer_32ksynct: .word OMAP2_L4_IO_ADDRESS(OMAP2420_32KSYNCT_BASE + 0x010) ENTRY(omap242x_sram_reprogram_sdrc_sz) .word . - omap242x_sram_reprogram_sdrc /* * Set dividers and pll. Also recalculate DLL value for DDR and unlock mode. */ .align 3 ENTRY(omap242x_sram_set_prcm) stmfd sp!, {r0-r12, lr} @ regs to stack adr r4, pbegin @ addr of preload start adr r8, pend @ addr of preload end mcrr p15, 1, r8, r4, c12 @ preload into icache pbegin: /* move into fast relock bypass */ ldr r8, omap242x_ssp_pll_ctl @ get addr ldr r5, [r8] @ get val mvn r6, #0x3 @ clear mask and r5, r5, r6 @ clear field orr r7, r5, #0x2 @ fast relock val str r7, [r8] @ go to fast relock ldr r4, omap242x_ssp_pll_stat @ addr of stat block: /* wait for bypass */ ldr r8, [r4] @ stat value and r8, r8, #0x3 @ mask for stat cmp r8, #0x1 @ there yet bne block @ loop if not /* set new dpll dividers _after_ in bypass */ ldr r4, omap242x_ssp_pll_div @ get addr str r0, [r4] @ set dpll ctrl val ldr r4, omap242x_ssp_set_config @ get addr mov r8, #1 @ valid cfg msk str r8, [r4] @ make dividers take mov r4, #100 @ dead spin a bit wait_a_bit: subs r4, r4, #1 @ dec loop bne wait_a_bit @ delay done? /* check if staying in bypass */ cmp r2, #0x1 @ stay in bypass? beq pend @ jump over dpll relock /* relock DPLL with new vals */ ldr r5, omap242x_ssp_pll_stat @ get addr ldr r4, omap242x_ssp_pll_ctl @ get addr orr r8, r7, #0x3 @ val for lock dpll str r8, [r4] @ set val mov r0, #1000 @ dead spin a bit wait_more: subs r0, r0, #1 @ dec loop bne wait_more @ delay done? wait_lock: ldr r8, [r5] @ get lock val and r8, r8, #3 @ isolate field cmp r8, #2 @ locked? bne wait_lock @ wait if not pend: /* update memory timings & briefly lock dll */ ldr r4, omap242x_ssp_sdrc_rfr @ get addr str r1, [r4] @ update refresh timing ldr r11, omap242x_ssp_dlla_ctrl @ get addr of DLLA ctrl ldr r10, [r11] @ get current val mvn r9, #0x4 @ mask to get clear bit2 and r10, r10, r9 @ clear bit2 for lock mode orr r10, r10, #0x8 @ make sure DLL on (es2 bit pos) str r10, [r11] @ commit to DLLA_CTRL add r11, r11, #0x8 @ move to dllb str r10, [r11] @ hit DLLB also mov r4, #0x800 @ relock time (min 0x400 L3 clocks) wait_dll_lock: subs r4, r4, #0x1 bne wait_dll_lock nop ldmfd sp!, {r0-r12, pc} @ restore regs and return omap242x_ssp_set_config: .word OMAP2420_PRCM_CLKCFG_CTRL omap242x_ssp_pll_ctl: .word OMAP2420_CM_REGADDR(PLL_MOD, CM_CLKEN) omap242x_ssp_pll_stat: .word OMAP2420_CM_REGADDR(PLL_MOD, CM_IDLEST) omap242x_ssp_pll_div: .word OMAP2420_CM_REGADDR(PLL_MOD, CM_CLKSEL1) omap242x_ssp_sdrc_rfr: .word OMAP242X_SDRC_REGADDR(SDRC_RFR_CTRL_0) omap242x_ssp_dlla_ctrl: .word OMAP242X_SDRC_REGADDR(SDRC_DLLA_CTRL) ENTRY(omap242x_sram_set_prcm_sz) .word . - omap242x_sram_set_prcm