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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /arch/arm/mach-omap2/sram242x.S
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/arm/mach-omap2/sram242x.S')
-rw-r--r--arch/arm/mach-omap2/sram242x.S317
1 files changed, 317 insertions, 0 deletions
diff --git a/arch/arm/mach-omap2/sram242x.S b/arch/arm/mach-omap2/sram242x.S
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+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * linux/arch/arm/mach-omap2/sram242x.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>
+ *
+ * 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(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
+ 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, 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
+ ret 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
+ ret 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