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-rw-r--r--kernel/arch/arm/mach-davinci/sleep.S228
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diff --git a/kernel/arch/arm/mach-davinci/sleep.S b/kernel/arch/arm/mach-davinci/sleep.S
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index 000000000..a5336a5e2
--- /dev/null
+++ b/kernel/arch/arm/mach-davinci/sleep.S
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+/*
+ * (C) Copyright 2009, Texas Instruments, Inc. http://www.ti.com/
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ *
+ * 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
+ */
+
+/* replicated define because linux/bitops.h cannot be included in assembly */
+#define BIT(nr) (1 << (nr))
+
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+#include <mach/psc.h>
+#include <mach/ddr2.h>
+
+#include "clock.h"
+
+/* Arbitrary, hardware currently does not update PHYRDY correctly */
+#define PHYRDY_CYCLES 0x1000
+
+/* Assume 25 MHz speed for the cycle conversions since PLLs are bypassed */
+#define PLL_BYPASS_CYCLES (PLL_BYPASS_TIME * 25)
+#define PLL_RESET_CYCLES (PLL_RESET_TIME * 25)
+#define PLL_LOCK_CYCLES (PLL_LOCK_TIME * 25)
+
+#define DEEPSLEEP_SLEEPENABLE_BIT BIT(31)
+
+ .text
+/*
+ * Move DaVinci into deep sleep state
+ *
+ * Note: This code is copied to internal SRAM by PM code. When the DaVinci
+ * wakes up it continues execution at the point it went to sleep.
+ * Register Usage:
+ * r0: contains virtual base for DDR2 controller
+ * r1: contains virtual base for DDR2 Power and Sleep controller (PSC)
+ * r2: contains PSC number for DDR2
+ * r3: contains virtual base DDR2 PLL controller
+ * r4: contains virtual address of the DEEPSLEEP register
+ */
+ENTRY(davinci_cpu_suspend)
+ stmfd sp!, {r0-r12, lr} @ save registers on stack
+
+ ldr ip, CACHE_FLUSH
+ blx ip
+
+ ldmia r0, {r0-r4}
+
+ /*
+ * Switch DDR to self-refresh mode.
+ */
+
+ /* calculate SDRCR address */
+ ldr ip, [r0, #DDR2_SDRCR_OFFSET]
+ bic ip, ip, #DDR2_SRPD_BIT
+ orr ip, ip, #DDR2_LPMODEN_BIT
+ str ip, [r0, #DDR2_SDRCR_OFFSET]
+
+ ldr ip, [r0, #DDR2_SDRCR_OFFSET]
+ orr ip, ip, #DDR2_MCLKSTOPEN_BIT
+ str ip, [r0, #DDR2_SDRCR_OFFSET]
+
+ mov ip, #PHYRDY_CYCLES
+1: subs ip, ip, #0x1
+ bne 1b
+
+ /* Disable DDR2 LPSC */
+ mov r7, r0
+ mov r0, #0x2
+ bl davinci_ddr_psc_config
+ mov r0, r7
+
+ /* Disable clock to DDR PHY */
+ ldr ip, [r3, #PLLDIV1]
+ bic ip, ip, #PLLDIV_EN
+ str ip, [r3, #PLLDIV1]
+
+ /* Put the DDR PLL in bypass and power down */
+ ldr ip, [r3, #PLLCTL]
+ bic ip, ip, #PLLCTL_PLLENSRC
+ bic ip, ip, #PLLCTL_PLLEN
+ str ip, [r3, #PLLCTL]
+
+ /* Wait for PLL to switch to bypass */
+ mov ip, #PLL_BYPASS_CYCLES
+2: subs ip, ip, #0x1
+ bne 2b
+
+ /* Power down the PLL */
+ ldr ip, [r3, #PLLCTL]
+ orr ip, ip, #PLLCTL_PLLPWRDN
+ str ip, [r3, #PLLCTL]
+
+ /* Go to deep sleep */
+ ldr ip, [r4]
+ orr ip, ip, #DEEPSLEEP_SLEEPENABLE_BIT
+ /* System goes to sleep beyond after this instruction */
+ str ip, [r4]
+
+ /* Wake up from sleep */
+
+ /* Clear sleep enable */
+ ldr ip, [r4]
+ bic ip, ip, #DEEPSLEEP_SLEEPENABLE_BIT
+ str ip, [r4]
+
+ /* initialize the DDR PLL controller */
+
+ /* Put PLL in reset */
+ ldr ip, [r3, #PLLCTL]
+ bic ip, ip, #PLLCTL_PLLRST
+ str ip, [r3, #PLLCTL]
+
+ /* Clear PLL power down */
+ ldr ip, [r3, #PLLCTL]
+ bic ip, ip, #PLLCTL_PLLPWRDN
+ str ip, [r3, #PLLCTL]
+
+ mov ip, #PLL_RESET_CYCLES
+3: subs ip, ip, #0x1
+ bne 3b
+
+ /* Bring PLL out of reset */
+ ldr ip, [r3, #PLLCTL]
+ orr ip, ip, #PLLCTL_PLLRST
+ str ip, [r3, #PLLCTL]
+
+ /* Wait for PLL to lock (assume prediv = 1, 25MHz OSCIN) */
+ mov ip, #PLL_LOCK_CYCLES
+4: subs ip, ip, #0x1
+ bne 4b
+
+ /* Remove PLL from bypass mode */
+ ldr ip, [r3, #PLLCTL]
+ bic ip, ip, #PLLCTL_PLLENSRC
+ orr ip, ip, #PLLCTL_PLLEN
+ str ip, [r3, #PLLCTL]
+
+ /* Start 2x clock to DDR2 */
+
+ ldr ip, [r3, #PLLDIV1]
+ orr ip, ip, #PLLDIV_EN
+ str ip, [r3, #PLLDIV1]
+
+ /* Enable VCLK */
+
+ /* Enable DDR2 LPSC */
+ mov r7, r0
+ mov r0, #0x3
+ bl davinci_ddr_psc_config
+ mov r0, r7
+
+ /* clear MCLKSTOPEN */
+
+ ldr ip, [r0, #DDR2_SDRCR_OFFSET]
+ bic ip, ip, #DDR2_MCLKSTOPEN_BIT
+ str ip, [r0, #DDR2_SDRCR_OFFSET]
+
+ ldr ip, [r0, #DDR2_SDRCR_OFFSET]
+ bic ip, ip, #DDR2_LPMODEN_BIT
+ str ip, [r0, #DDR2_SDRCR_OFFSET]
+
+ /* Restore registers and return */
+ ldmfd sp!, {r0-r12, pc}
+
+ENDPROC(davinci_cpu_suspend)
+
+/*
+ * Disables or Enables DDR2 LPSC
+ * Register Usage:
+ * r0: Enable or Disable LPSC r0 = 0x3 => Enable, r0 = 0x2 => Disable LPSC
+ * r1: contains virtual base for DDR2 Power and Sleep controller (PSC)
+ * r2: contains PSC number for DDR2
+ */
+ENTRY(davinci_ddr_psc_config)
+ /* Set next state in mdctl for DDR2 */
+ mov r6, #MDCTL
+ add r6, r6, r2, lsl #2
+ ldr ip, [r1, r6]
+ bic ip, ip, #MDSTAT_STATE_MASK
+ orr ip, ip, r0
+ str ip, [r1, r6]
+
+ /* Enable the Power Domain Transition Command */
+ ldr ip, [r1, #PTCMD]
+ orr ip, ip, #0x1
+ str ip, [r1, #PTCMD]
+
+ /* Check for Transition Complete (PTSTAT) */
+ptstat_done:
+ ldr ip, [r1, #PTSTAT]
+ and ip, ip, #0x1
+ cmp ip, #0x0
+ bne ptstat_done
+
+ /* Check for DDR2 clock disable completion; */
+ mov r6, #MDSTAT
+ add r6, r6, r2, lsl #2
+ddr2clk_stop_done:
+ ldr ip, [r1, r6]
+ and ip, ip, #MDSTAT_STATE_MASK
+ cmp ip, r0
+ bne ddr2clk_stop_done
+
+ ret lr
+ENDPROC(davinci_ddr_psc_config)
+
+CACHE_FLUSH:
+#ifdef CONFIG_CPU_V6
+ .word v6_flush_kern_cache_all
+#else
+ .word arm926_flush_kern_cache_all
+#endif
+
+ENTRY(davinci_cpu_suspend_sz)
+ .word . - davinci_cpu_suspend
+ENDPROC(davinci_cpu_suspend_sz)