ARM: OMAP2: Move sleep.S into sleep24xx.S

Some register offsets are different for 242x and 243x. This
will allow compiling sleep code for both chips into the same
kernel. Pass the addresses for SDRC_DDLA_CTRL and SDRC_POWER to the
omap24xx_cpu_suspend instead of loading the values since the only.

Also fix a bug to call omap2_sram_suspend with the value of SDRC_DLLA_CTRL
instead of the address as that's what omap24xx_cpu_suspend expects to
determine between DDR and SDR. This bug has not been noticed as
the boards seem to have DDR instead of SDR.

Note that some PM patches are still missing. The PM patches will
be added later on once the base files are in sync with linux-omap
tree.

Signed-off-by: Tony Lindgren <tony@atomide.com>

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