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-rw-r--r--arch/arm/mach-omap2/sram34xx.S222
1 files changed, 134 insertions, 88 deletions
diff --git a/arch/arm/mach-omap2/sram34xx.S b/arch/arm/mach-omap2/sram34xx.S
index 2c7146136342..f41f8d96ddba 100644
--- a/arch/arm/mach-omap2/sram34xx.S
+++ b/arch/arm/mach-omap2/sram34xx.S
@@ -3,13 +3,12 @@
*
* Omap3 specific functions that need to be run in internal SRAM
*
- * (C) Copyright 2007
- * Texas Instruments Inc.
- * Rajendra Nayak <rnayak@ti.com>
+ * Copyright (C) 2004, 2007, 2008 Texas Instruments, Inc.
+ * Copyright (C) 2008 Nokia Corporation
*
- * (C) Copyright 2004
- * Texas Instruments, <www.ti.com>
+ * Rajendra Nayak <rnayak@ti.com>
* Richard Woodruff <r-woodruff2@ti.com>
+ * Paul Walmsley
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
@@ -37,121 +36,166 @@
.text
+/* r4 parameters */
+#define SDRC_NO_UNLOCK_DLL 0x0
+#define SDRC_UNLOCK_DLL 0x1
+
+/* SDRC_DLLA_CTRL bit settings */
+#define FIXEDDELAY_SHIFT 24
+#define FIXEDDELAY_MASK (0xff << FIXEDDELAY_SHIFT)
+#define DLLIDLE_MASK 0x4
+
+/*
+ * SDRC_DLLA_CTRL default values: TI hardware team indicates that
+ * FIXEDDELAY should be initialized to 0xf. This apparently was
+ * empirically determined during process testing, so no derivation
+ * was provided.
+ */
+#define FIXEDDELAY_DEFAULT (0x0f << FIXEDDELAY_SHIFT)
+
+/* SDRC_DLLA_STATUS bit settings */
+#define LOCKSTATUS_MASK 0x4
+
+/* SDRC_POWER bit settings */
+#define SRFRONIDLEREQ_MASK 0x40
+#define PWDENA_MASK 0x4
+
+/* CM_IDLEST1_CORE bit settings */
+#define ST_SDRC_MASK 0x2
+
+/* CM_ICLKEN1_CORE bit settings */
+#define EN_SDRC_MASK 0x2
+
+/* CM_CLKSEL1_PLL bit settings */
+#define CORE_DPLL_CLKOUT_DIV_SHIFT 0x1b
+
/*
- * Change frequency of core dpll
- * r0 = sdrc_rfr_ctrl r1 = sdrc_actim_ctrla r2 = sdrc_actim_ctrlb r3 = M2
+ * omap3_sram_configure_core_dpll - change DPLL3 M2 divider
+ * r0 = new SDRC_RFR_CTRL register contents
+ * r1 = new SDRC_ACTIM_CTRLA register contents
+ * r2 = new SDRC_ACTIM_CTRLB register contents
+ * r3 = new M2 divider setting (only 1 and 2 supported right now)
+ * r4 = unlock SDRC DLL? (1 = yes, 0 = no). Only unlock DLL for
+ * SDRC rates < 83MHz
+ * r5 = number of MPU cycles to wait for SDRC to stabilize after
+ * reprogramming the SDRC when switching to a slower MPU speed
+ * r6 = new SDRC_MR_0 register value
+ * r7 = increasing SDRC rate? (1 = yes, 0 = no)
+ *
*/
ENTRY(omap3_sram_configure_core_dpll)
stmfd sp!, {r1-r12, lr} @ store regs to stack
- cmp r3, #0x2
- blne configure_sdrc
- cmp r3, #0x2
+ ldr r4, [sp, #52] @ pull extra args off the stack
+ ldr r5, [sp, #56] @ load extra args from the stack
+ ldr r6, [sp, #60] @ load extra args from the stack
+ ldr r7, [sp, #64] @ load extra args from the stack
+ dsb @ flush buffered writes to interconnect
+ cmp r7, #1 @ if increasing SDRC clk rate,
+ bleq configure_sdrc @ program the SDRC regs early (for RFR)
+ cmp r4, #SDRC_UNLOCK_DLL @ set the intended DLL state
+ 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
+ bl sdram_in_selfrefresh @ put SDRAM in self refresh, idle SDRC
+ bl configure_core_dpll @ change the DPLL3 M2 divider
+ bl enable_sdrc @ take SDRC out of idle
+ cmp r4, #SDRC_UNLOCK_DLL @ wait for DLL status to change
+ bleq wait_dll_unlock
blne wait_dll_lock
- cmp r3, #0x1
- blne configure_sdrc
+ cmp r7, #1 @ if increasing SDRC clk rate,
+ beq return_to_sdram @ return to SDRAM code, otherwise,
+ bl configure_sdrc @ reprogram SDRC regs now
+ mov r12, r5
+ bl wait_clk_stable @ wait for SDRC to stabilize
+return_to_sdram:
+ 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]
+ and r12, r12, #FIXEDDELAY_MASK
+ orr r12, r12, #FIXEDDELAY_DEFAULT
+ orr r12, r12, #DLLIDLE_MASK
+ 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, #DLLIDLE_MASK
+ 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, #SRFRONIDLEREQ_MASK @ enable self refresh on idle
+ bic r12, r12, #PWDENA_MASK @ clear PWDENA
+ str r12, [r11] @ write back to SDRC_POWER register
+ ldr r12, [r11] @ posted-write barrier for SDRC
+idle_sdrc:
+ ldr r11, omap3_cm_iclken1_core @ read the CM_ICLKEN1_CORE reg
+ ldr r12, [r11]
+ bic r12, r12, #EN_SDRC_MASK @ 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, #ST_SDRC_MASK @ check for SDRC idle
+ cmp r12, #ST_SDRC_MASK
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
- cmp r3, #2
- bne wait_clk_stable
+ 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 #CORE_DPLL_CLKOUT_DIV_SHIFT
+ str r12, [r11]
+ ldr r12, [r11] @ posted-write barrier for CM
bx lr
wait_clk_stable:
- subs r5, r5, #1
+ subs r12, r12, #1
bne wait_clk_stable
- nop
- nop
- nop
- nop
- nop
- nop
- nop
- nop
- nop
- 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, #EN_SDRC_MASK @ 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, #ST_SDRC_MASK
+ 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, #LOCKSTATUS_MASK
+ cmp r12, #LOCKSTATUS_MASK
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, #LOCKSTATUS_MASK
+ 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 r11, omap3_sdrc_mr_0
+ str r6, [r11]
+ ldr r6, [r11] @ posted-write barrier for SDRC
bx lr
omap3_sdrc_power:
@@ -168,6 +212,8 @@ omap3_sdrc_actim_ctrla:
.word OMAP34XX_SDRC_REGADDR(SDRC_ACTIM_CTRL_A_0)
omap3_sdrc_actim_ctrlb:
.word OMAP34XX_SDRC_REGADDR(SDRC_ACTIM_CTRL_B_0)
+omap3_sdrc_mr_0:
+ .word OMAP34XX_SDRC_REGADDR(SDRC_MR_0)
omap3_sdrc_dlla_status:
.word OMAP34XX_SDRC_REGADDR(SDRC_DLLA_STATUS)
omap3_sdrc_dlla_ctrl: