summaryrefslogtreecommitdiffstats
path: root/kernel/arch/arm/mach-omap2/sram34xx.S
diff options
context:
space:
mode:
Diffstat (limited to 'kernel/arch/arm/mach-omap2/sram34xx.S')
-rw-r--r--kernel/arch/arm/mach-omap2/sram34xx.S346
1 files changed, 346 insertions, 0 deletions
diff --git a/kernel/arch/arm/mach-omap2/sram34xx.S b/kernel/arch/arm/mach-omap2/sram34xx.S
new file mode 100644
index 000000000..1446331b5
--- /dev/null
+++ b/kernel/arch/arm/mach-omap2/sram34xx.S
@@ -0,0 +1,346 @@
+/*
+ * linux/arch/arm/mach-omap3/sram.S
+ *
+ * Omap3 specific functions that need to be run in internal SRAM
+ *
+ * Copyright (C) 2004, 2007, 2008 Texas Instruments, Inc.
+ * Copyright (C) 2008 Nokia Corporation
+ *
+ * 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
+ * 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
+ */
+#include <linux/linkage.h>
+
+#include <asm/assembler.h>
+
+#include "soc.h"
+#include "iomap.h"
+#include "sdrc.h"
+#include "cm3xxx.h"
+
+/*
+ * This file needs be built unconditionally as ARM to interoperate correctly
+ * with non-Thumb-2-capable firmware.
+ */
+ .arm
+
+ .text
+
+/* r1 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
+
+/* 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
+
+/*
+ * omap3_sram_configure_core_dpll - change DPLL3 M2 divider
+ *
+ * Params passed in registers:
+ * r0 = new M2 divider setting (only 1 and 2 supported right now)
+ * r1 = unlock SDRC DLL? (1 = yes, 0 = no). Only unlock DLL for
+ * SDRC rates < 83MHz
+ * r2 = number of MPU cycles to wait for SDRC to stabilize after
+ * reprogramming the SDRC when switching to a slower MPU speed
+ * r3 = increasing SDRC rate? (1 = yes, 0 = no)
+ *
+ * Params passed via the stack. The needed params will be copied in SRAM
+ * before use by the code in SRAM (SDRAM is not accessible during SDRC
+ * reconfiguration):
+ * new SDRC_RFR_CTRL_0 register contents
+ * new SDRC_ACTIM_CTRL_A_0 register contents
+ * new SDRC_ACTIM_CTRL_B_0 register contents
+ * new SDRC_MR_0 register value
+ * new SDRC_RFR_CTRL_1 register contents
+ * new SDRC_ACTIM_CTRL_A_1 register contents
+ * new SDRC_ACTIM_CTRL_B_1 register contents
+ * new SDRC_MR_1 register value
+ *
+ * If the param SDRC_RFR_CTRL_1 is 0, the parameters are not programmed into
+ * the SDRC CS1 registers
+ *
+ * NOTE: This code no longer attempts to program the SDRC AC timing and MR
+ * registers. This is because the code currently cannot ensure that all
+ * L3 initiators (e.g., sDMA, IVA, DSS DISPC, etc.) are not accessing the
+ * SDRAM when the registers are written. If the registers are changed while
+ * an initiator is accessing SDRAM, memory can be corrupted and/or the SDRC
+ * may enter an unpredictable state. In the future, the intent is to
+ * re-enable this code in cases where we can ensure that no initiators are
+ * touching the SDRAM. Until that time, users who know that their use case
+ * can satisfy the above requirement can enable the CONFIG_OMAP3_SDRC_AC_TIMING
+ * option.
+ *
+ * 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.
+ */
+ .align 3
+ENTRY(omap3_sram_configure_core_dpll)
+ stmfd sp!, {r1-r12, lr} @ store regs to stack
+
+ @ pull the extra args off the stack
+ @ and store them in SRAM
+
+/*
+ * PC-relative stores are deprecated in ARMv7 and lead to undefined behaviour
+ * in Thumb-2: use a r7 as a base instead.
+ * Be careful not to clobber r7 when maintaing this file.
+ */
+ THUMB( adr r7, omap3_sram_configure_core_dpll )
+ .macro strtext Rt:req, label:req
+ ARM( str \Rt, \label )
+ THUMB( str \Rt, [r7, \label - omap3_sram_configure_core_dpll] )
+ .endm
+
+ ldr r4, [sp, #52]
+ strtext r4, omap_sdrc_rfr_ctrl_0_val
+ ldr r4, [sp, #56]
+ strtext r4, omap_sdrc_actim_ctrl_a_0_val
+ ldr r4, [sp, #60]
+ strtext r4, omap_sdrc_actim_ctrl_b_0_val
+ ldr r4, [sp, #64]
+ strtext r4, omap_sdrc_mr_0_val
+ ldr r4, [sp, #68]
+ strtext r4, omap_sdrc_rfr_ctrl_1_val
+ cmp r4, #0 @ if SDRC_RFR_CTRL_1 is 0,
+ beq skip_cs1_params @ do not use cs1 params
+ ldr r4, [sp, #72]
+ strtext r4, omap_sdrc_actim_ctrl_a_1_val
+ ldr r4, [sp, #76]
+ strtext r4, omap_sdrc_actim_ctrl_b_1_val
+ ldr r4, [sp, #80]
+ strtext r4, omap_sdrc_mr_1_val
+skip_cs1_params:
+ mrc p15, 0, r8, c1, c0, 0 @ read ctrl register
+ bic r10, r8, #0x800 @ clear Z-bit, disable branch prediction
+ mcr p15, 0, r10, c1, c0, 0 @ write ctrl register
+ dsb @ flush buffered writes to interconnect
+ isb @ prevent speculative exec past here
+ cmp r3, #1 @ if increasing SDRC clk rate,
+ bleq configure_sdrc @ program the SDRC regs early (for RFR)
+ cmp r1, #SDRC_UNLOCK_DLL @ set the intended DLL state
+ bleq unlock_dll
+ blne lock_dll
+ bl sdram_in_selfrefresh @ put SDRAM in self refresh, idle SDRC
+ bl configure_core_dpll @ change the DPLL3 M2 divider
+ mov r12, r2
+ bl wait_clk_stable @ wait for SDRC to stabilize
+ bl enable_sdrc @ take SDRC out of idle
+ cmp r1, #SDRC_UNLOCK_DLL @ wait for DLL status to change
+ bleq wait_dll_unlock
+ blne wait_dll_lock
+ cmp r3, #1 @ if increasing SDRC clk rate,
+ beq return_to_sdram @ return to SDRAM code, otherwise,
+ bl configure_sdrc @ reprogram SDRC regs now
+return_to_sdram:
+ mcr p15, 0, r8, c1, c0, 0 @ restore ctrl register
+ isb @ prevent speculative exec past here
+ mov r0, #0 @ return value
+ ldmfd sp!, {r1-r12, pc} @ restore regs and return
+unlock_dll:
+ ldr r11, omap3_sdrc_dlla_ctrl
+ ldr r12, [r11]
+ bic 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 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:
+ 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
+ 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 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 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, r0, lsl #CORE_DPLL_CLKOUT_DIV_SHIFT
+ str r12, [r11]
+ ldr r12, [r11] @ posted-write barrier for CM
+ bx lr
+wait_clk_stable:
+ subs r12, r12, #1
+ bne wait_clk_stable
+ bx lr
+enable_sdrc:
+ 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 r11, omap3_cm_idlest1_core
+ ldr r12, [r11]
+ and r12, r12, #ST_SDRC_MASK
+ cmp r12, #0
+ bne wait_sdrc_idle1
+restore_sdrc_power_val:
+ ldr r11, omap3_sdrc_power
+ str r9, [r11] @ restore SDRC_POWER, no barrier needed
+ bx lr
+wait_dll_lock:
+ 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 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 r12, omap_sdrc_rfr_ctrl_0_val @ fetch value from SRAM
+ ldr r11, omap3_sdrc_rfr_ctrl_0 @ fetch addr from SRAM
+ str r12, [r11] @ store
+#ifdef CONFIG_OMAP3_SDRC_AC_TIMING
+ ldr r12, omap_sdrc_actim_ctrl_a_0_val
+ ldr r11, omap3_sdrc_actim_ctrl_a_0
+ str r12, [r11]
+ ldr r12, omap_sdrc_actim_ctrl_b_0_val
+ ldr r11, omap3_sdrc_actim_ctrl_b_0
+ str r12, [r11]
+ ldr r12, omap_sdrc_mr_0_val
+ ldr r11, omap3_sdrc_mr_0
+ str r12, [r11]
+#endif
+ ldr r12, omap_sdrc_rfr_ctrl_1_val
+ cmp r12, #0 @ if SDRC_RFR_CTRL_1 is 0,
+ beq skip_cs1_prog @ do not program cs1 params
+ ldr r11, omap3_sdrc_rfr_ctrl_1
+ str r12, [r11]
+#ifdef CONFIG_OMAP3_SDRC_AC_TIMING
+ ldr r12, omap_sdrc_actim_ctrl_a_1_val
+ ldr r11, omap3_sdrc_actim_ctrl_a_1
+ str r12, [r11]
+ ldr r12, omap_sdrc_actim_ctrl_b_1_val
+ ldr r11, omap3_sdrc_actim_ctrl_b_1
+ str r12, [r11]
+ ldr r12, omap_sdrc_mr_1_val
+ ldr r11, omap3_sdrc_mr_1
+ str r12, [r11]
+#endif
+skip_cs1_prog:
+ ldr r12, [r11] @ posted-write barrier for SDRC
+ bx lr
+
+ .align
+omap3_sdrc_power:
+ .word OMAP34XX_SDRC_REGADDR(SDRC_POWER)
+omap3_cm_clksel1_pll:
+ .word OMAP34XX_CM_REGADDR(PLL_MOD, CM_CLKSEL1)
+omap3_cm_idlest1_core:
+ .word OMAP34XX_CM_REGADDR(CORE_MOD, CM_IDLEST)
+omap3_cm_iclken1_core:
+ .word OMAP34XX_CM_REGADDR(CORE_MOD, CM_ICLKEN1)
+
+omap3_sdrc_rfr_ctrl_0:
+ .word OMAP34XX_SDRC_REGADDR(SDRC_RFR_CTRL_0)
+omap3_sdrc_rfr_ctrl_1:
+ .word OMAP34XX_SDRC_REGADDR(SDRC_RFR_CTRL_1)
+omap3_sdrc_actim_ctrl_a_0:
+ .word OMAP34XX_SDRC_REGADDR(SDRC_ACTIM_CTRL_A_0)
+omap3_sdrc_actim_ctrl_a_1:
+ .word OMAP34XX_SDRC_REGADDR(SDRC_ACTIM_CTRL_A_1)
+omap3_sdrc_actim_ctrl_b_0:
+ .word OMAP34XX_SDRC_REGADDR(SDRC_ACTIM_CTRL_B_0)
+omap3_sdrc_actim_ctrl_b_1:
+ .word OMAP34XX_SDRC_REGADDR(SDRC_ACTIM_CTRL_B_1)
+omap3_sdrc_mr_0:
+ .word OMAP34XX_SDRC_REGADDR(SDRC_MR_0)
+omap3_sdrc_mr_1:
+ .word OMAP34XX_SDRC_REGADDR(SDRC_MR_1)
+omap_sdrc_rfr_ctrl_0_val:
+ .word 0xDEADBEEF
+omap_sdrc_rfr_ctrl_1_val:
+ .word 0xDEADBEEF
+omap_sdrc_actim_ctrl_a_0_val:
+ .word 0xDEADBEEF
+omap_sdrc_actim_ctrl_a_1_val:
+ .word 0xDEADBEEF
+omap_sdrc_actim_ctrl_b_0_val:
+ .word 0xDEADBEEF
+omap_sdrc_actim_ctrl_b_1_val:
+ .word 0xDEADBEEF
+omap_sdrc_mr_0_val:
+ .word 0xDEADBEEF
+omap_sdrc_mr_1_val:
+ .word 0xDEADBEEF
+
+omap3_sdrc_dlla_status:
+ .word OMAP34XX_SDRC_REGADDR(SDRC_DLLA_STATUS)
+omap3_sdrc_dlla_ctrl:
+ .word OMAP34XX_SDRC_REGADDR(SDRC_DLLA_CTRL)
+core_m2_mask_val:
+ .word 0x07FFFFFF
+ENDPROC(omap3_sram_configure_core_dpll)
+
+ENTRY(omap3_sram_configure_core_dpll_sz)
+ .word . - omap3_sram_configure_core_dpll
+