1 files changed, 126 insertions, 0 deletions

diff --git a/arch/arm/mach-omap2/sleep24xx.S b/arch/arm/mach-omap2/sleep24xx.S
new file mode 100644
index 00000000000..43336b93b21
--- /dev/null
+++ b/arch/arm/mach-omap2/sleep24xx.S
@@ -0,0 +1,126 @@
+/*
+ * linux/arch/arm/mach-omap2/sleep.S
+ *
+ * (C) Copyright 2004
+ * Texas Instruments, <www.ti.com>
+ * Richard Woodruff <r-woodruff2@ti.com>
+ *
+ * (C) Copyright 2006 Nokia Corporation
+ * Fixed idle loop sleep
+ * Igor Stoppa <igor.stoppa@nokia.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
+ */
+
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+#include <mach/io.h>
+#include <mach/pm.h>
+
+#include <mach/omap24xx.h>
+
+#include "sdrc.h"
+
+/* First address of reserved address space?  apparently valid for OMAP2 & 3 */
+#define A_SDRC0_V               (0xC0000000)
+
+        .text
+
+/*
+ * Forces OMAP into idle state
+ *
+ * omap24xx_idle_loop_suspend() - This bit of code just executes the WFI
+ * for normal idles.
+ *
+ * Note: This code get's copied to internal SRAM at boot. When the OMAP
+ *       wakes up it continues execution at the point it went to sleep.
+ */
+ENTRY(omap24xx_idle_loop_suspend)
+        stmfd   sp!, {r0, lr}           @ save registers on stack
+        mov     r0, #0                  @ clear for mcr setup
+        mcr     p15, 0, r0, c7, c0, 4   @ wait for interrupt
+        ldmfd   sp!, {r0, pc}           @ restore regs and return
+
+ENTRY(omap24xx_idle_loop_suspend_sz)
+        .word   . - omap24xx_idle_loop_suspend
+
+/*
+ * omap24xx_cpu_suspend() - Forces OMAP into deep sleep state by completing
+ * SDRC shutdown then ARM shutdown.  Upon wake MPU is back on so just restore
+ * SDRC.
+ *
+ * Input:
+ * R0 : DLL ctrl value pre-Sleep
+ * R1 : SDRC_DLLA_CTRL
+ * R2 : SDRC_POWER
+ *
+ * The if the DPLL is going to AutoIdle. It seems like the DPLL may be back on
+ * when we get called, but the DLL probably isn't.  We will wait a bit more in
+ * case the DPLL isn't quite there yet. The code will wait on DLL for DDR even
+ * if in unlocked mode.
+ *
+ * For less than 242x-ES2.2 upon wake from a sleep mode where the external
+ * oscillator was stopped, a timing bug exists where a non-stabilized 12MHz
+ * clock can pass into the PRCM can cause problems at DSP and IVA.
+ * To work around this the code will switch to the 32kHz source prior to sleep.
+ * Post sleep we will shift back to using the DPLL.  Apparently,
+ * CM_IDLEST_CLKGEN does not reflect the full clock change so you need to wait
+ * 3x12MHz + 3x32kHz clocks for a full switch.
+ *
+ * The DLL load value is not kept in RETENTION or OFF.  It needs to be restored
+ * at wake
+ */
+ENTRY(omap24xx_cpu_suspend)
+        stmfd   sp!, {r0 - r12, lr}     @ save registers on stack
+        mov     r3, #0x0                @ clear for mcr call
+        mcr     p15, 0, r3, c7, c10, 4  @ memory barrier, hope SDR/DDR finished
+        nop
+        nop
+        ldr     r4, [r2]                @ read SDRC_POWER
+        orr     r4, r4, #0x40           @ enable self refresh on idle req
+        mov     r5, #0x2000             @ set delay (DPLL relock + DLL relock)
+        str     r4, [r2]                @ make it so
+        mov     r2, #0
+        nop
+        mcr     p15, 0, r2, c7, c0, 4   @ wait for interrupt
+        nop
+loop:
+        subs    r5, r5, #0x1            @ awake, wait just a bit
+        bne     loop
+
+        /* The DPLL has to be on before we take the DDR out of self refresh */
+        bic     r4, r4, #0x40           @ now clear self refresh bit.
+        str     r4, [r2]                @ write to SDRC_POWER
+        ldr     r4, A_SDRC0             @ make a clock happen
+        ldr     r4, [r4]                @ read A_SDRC0
+        nop                             @ start auto refresh only after clk ok
+        movs    r0, r0                  @ see if DDR or SDR
+        strne   r0, [r1]                @ rewrite DLLA to force DLL reload
+        addne   r1, r1, #0x8            @ move to DLLB
+        strne   r0, [r1]                @ rewrite DLLB to force DLL reload
+
+        mov     r5, #0x1000
+loop2:
+        subs    r5, r5, #0x1
+        bne     loop2
+        /* resume*/
+        ldmfd   sp!, {r0 - r12, pc}     @ restore regs and return
+
+A_SDRC0:
+        .word A_SDRC0_V
+
+ENTRY(omap24xx_cpu_suspend_sz)
+        .word   . - omap24xx_cpu_suspend