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Diffstat (limited to '')
-rw-r--r-- | arch/arm/mach-omap2/sram243x.S | 331 |
1 files changed, 331 insertions, 0 deletions
diff --git a/arch/arm/mach-omap2/sram243x.S b/arch/arm/mach-omap2/sram243x.S new file mode 100644 index 000000000..b3edd6f7f --- /dev/null +++ b/arch/arm/mach-omap2/sram243x.S @@ -0,0 +1,331 @@ +/* + * linux/arch/arm/mach-omap2/sram243x.S + * + * Omap2 specific functions that need to be run in internal SRAM + * + * (C) Copyright 2004 + * Texas Instruments, <www.ti.com> + * Richard Woodruff <r-woodruff2@ti.com> + * + * 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 <linux/linkage.h> + +#include <asm/assembler.h> + +#include "soc.h" +#include "iomap.h" +#include "prm2xxx.h" +#include "cm2xxx.h" +#include "sdrc.h" + + .text + + .align 3 +ENTRY(omap243x_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, omap243x_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, omap243x_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 + ret 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, omap243x_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, omap243x_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 + ret lr @ back to caller. + +omap243x_sdi_cm_clksel2_pll: + .word OMAP2430_CM_REGADDR(PLL_MOD, CM_CLKSEL2) +omap243x_sdi_sdrc_dlla_ctrl: + .word OMAP243X_SDRC_REGADDR(SDRC_DLLA_CTRL) +omap243x_sdi_prcm_voltctrl: + .word OMAP2430_PRCM_VOLTCTRL +prcm_mask_val: + .word 0xFFFF3FFC +omap243x_sdi_timer_32ksynct_cr: + .word OMAP2_L4_IO_ADDRESS(OMAP2430_32KSYNCT_BASE + 0x010) +ENTRY(omap243x_sram_ddr_init_sz) + .word . - omap243x_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(omap243x_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, omap243x_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, omap243x_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, omap243x_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, omap243x_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, omap243x_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 + ret lr @ back to caller + +omap243x_srs_cm_clksel2_pll: + .word OMAP2430_CM_REGADDR(PLL_MOD, CM_CLKSEL2) +omap243x_srs_sdrc_dlla_ctrl: + .word OMAP243X_SDRC_REGADDR(SDRC_DLLA_CTRL) +omap243x_srs_sdrc_rfr_ctrl: + .word OMAP243X_SDRC_REGADDR(SDRC_RFR_CTRL_0) +omap243x_srs_prcm_voltctrl: + .word OMAP2430_PRCM_VOLTCTRL +ddr_prcm_mask_val: + .word 0xFFFF3FFC +omap243x_srs_timer_32ksynct: + .word OMAP2_L4_IO_ADDRESS(OMAP2430_32KSYNCT_BASE + 0x010) + +ENTRY(omap243x_sram_reprogram_sdrc_sz) + .word . - omap243x_sram_reprogram_sdrc + +/* + * Set dividers and pll. Also recalculate DLL value for DDR and unlock mode. + */ + .align 3 +ENTRY(omap243x_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, omap243x_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, omap243x_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, omap243x_ssp_pll_div @ get addr + str r0, [r4] @ set dpll ctrl val + + ldr r4, omap243x_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, omap243x_ssp_pll_stat @ get addr + ldr r4, omap243x_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, omap243x_ssp_sdrc_rfr @ get addr + str r1, [r4] @ update refresh timing + ldr r11, omap243x_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 + +omap243x_ssp_set_config: + .word OMAP2430_PRCM_CLKCFG_CTRL +omap243x_ssp_pll_ctl: + .word OMAP2430_CM_REGADDR(PLL_MOD, CM_CLKEN) +omap243x_ssp_pll_stat: + .word OMAP2430_CM_REGADDR(PLL_MOD, CM_IDLEST) +omap243x_ssp_pll_div: + .word OMAP2430_CM_REGADDR(PLL_MOD, CM_CLKSEL1) +omap243x_ssp_sdrc_rfr: + .word OMAP243X_SDRC_REGADDR(SDRC_RFR_CTRL_0) +omap243x_ssp_dlla_ctrl: + .word OMAP243X_SDRC_REGADDR(SDRC_DLLA_CTRL) + +ENTRY(omap243x_sram_set_prcm_sz) + .word . - omap243x_sram_set_prcm |