Commit 3348f4fc authored by Ranjani Vaidyanathan's avatar Ranjani Vaidyanathan

ENGR00220696 [MX6SL]-Reduce IDLE mode power consumption.

When ARM enters WFI in low power IDLE state, float the DDR
IO pins to drop the power on the VDDHIGH rail.
Need to run WFI code from IRAM since DDR needs to be
put into self-refresh before changing the IO pins.
Drop AHB to 8MHz and DDR to 1MHz when ARM is in WFI when
in IDLE state.
Set IPG_PERCLK to run at 3MHz, since we want to maintain a
1:2.5 ratio between PERCLK to AHB_CLK.
Signed-off-by: default avatarRanjani Vaidyanathan <ra5478@freescale.com>
parent 5d309473
......@@ -5,7 +5,7 @@
# Object file lists.
obj-y := cpu.o mm.o system.o devices.o dummy_gpio.o irq.o bus_freq.o usb_dr.o usb_h2.o usb_h3.o\
pm.o cpu_op-mx6.o mx6_wfi.o mx6_fec.o mx6_anatop_regulator.o cpu_regulator-mx6.o \
mx6_mmdc.o mx6_ddr_freq.o mx6sl_ddr.o
mx6_mmdc.o mx6_ddr_freq.o mx6sl_ddr.o mx6sl_wfi.o
obj-$(CONFIG_ARCH_MX6) += clock.o mx6_suspend.o clock_mx6sl.o
obj-$(CONFIG_MACH_MX6Q_ARM2) += board-mx6q_arm2.o
......
......@@ -75,6 +75,9 @@ unsigned int ddr_normal_rate;
int low_freq_bus_used(void);
void set_ddr_freq(int ddr_freq);
void *mx6sl_wfi_iram_base;
void (*mx6sl_wfi_iram)(int arm_podf, unsigned long wfi_iram_addr) = NULL;
extern void mx6sl_wait (int arm_podf, unsigned long wfi_iram_addr);
void *mx6sl_ddr_freq_base;
void (*mx6sl_ddr_freq_change_iram)(int ddr_freq) = NULL;
......@@ -84,7 +87,6 @@ extern int init_mmdc_settings(void);
extern struct cpu_op *(*get_cpu_op)(int *op);
extern int update_ddr_freq(int ddr_rate);
extern int chip_rev;
extern bool arm_mem_clked_in_wait;
DEFINE_MUTEX(bus_freq_mutex);
......@@ -153,8 +155,6 @@ static void reduce_bus_freq_handler(struct work_struct *work)
u32 div;
unsigned long flags;
arm_mem_clked_in_wait = true;
spin_lock_irqsave(&freq_lock, flags);
/* Set periph_clk to be sourced from OSC_CLK */
......@@ -177,7 +177,7 @@ static void reduce_bus_freq_handler(struct work_struct *work)
;
clk_set_parent(pll1_sw_clk, pll1);
/* Now change DDR freq in IRAM. */
/* Now change DDR freq while running from IRAM. */
mx6sl_ddr_freq_change_iram(LPAPM_CLK);
low_bus_freq_mode = 1;
......@@ -308,9 +308,6 @@ int set_high_bus_freq(int high_bus_freq)
clk_disable(pll3);
}
if (cpu_is_mx6sl())
arm_mem_clked_in_wait = false;
mutex_unlock(&bus_freq_mutex);
return 0;
}
......@@ -618,7 +615,6 @@ static int __devinit busfreq_probe(struct platform_device *pdev)
if (!cpu_is_mx6sl())
init_mmdc_settings();
else {
#if 1
unsigned long iram_paddr;
/* Allocate IRAM for WFI code when system is
......@@ -628,12 +624,22 @@ static int __devinit busfreq_probe(struct platform_device *pdev)
/* Need to remap the area here since we want
* the memory region to be executable.
*/
mx6sl_wfi_iram_base = __arm_ioremap(iram_paddr,
SZ_4K, MT_MEMORY_NONCACHED);
memcpy(mx6sl_wfi_iram_base, mx6sl_wait, SZ_4K);
mx6sl_wfi_iram = (void *)mx6sl_wfi_iram_base;
/* Allocate IRAM for WFI code when system is
*in low freq mode.
*/
iram_alloc(SZ_4K, &iram_paddr);
/* Need to remap the area here since we want the memory region
to be executable. */
mx6sl_ddr_freq_base = __arm_ioremap(iram_paddr,
SZ_4K, MT_MEMORY_NONCACHED);
memcpy(mx6sl_ddr_freq_base, mx6sl_ddr_iram, SZ_4K);
mx6sl_ddr_freq_change_iram = (void *)mx6sl_ddr_freq_base;
#endif
}
return 0;
......
......@@ -4000,6 +4000,12 @@ int __init mx6sl_clocks_init(unsigned long ckil, unsigned long osc,
* should be from OSC24M */
clk_set_parent(&ipg_perclk, &osc_clk);
/* Need to set IPG_PERCLK to 3MHz, so that we can
* satisfy the 2.5:1 AHB:IPG_PERCLK ratio. Since AHB
* can be dropped to as low as 8MHz in low power mode.
*/
clk_set_rate(&ipg_perclk, 3000000);
gpt_clk[0].parent = &ipg_perclk;
gpt_clk[0].get_rate = NULL;
......
/*
* Copyright (C) 2012 Freescale Semiconductor, Inc. All Rights Reserved.
*
* 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.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include <linux/linkage.h>
#include <mach/hardware.h>
#define IRAM_WAIT_SIZE (1 << 11)
.macro sl_ddr_io_save
ldr r4, [r1, #0x30c] /* DRAM_DQM0 */
ldr r5, [r1, #0x310] /* DRAM_DQM1 */
ldr r6, [r1, #0x314] /* DRAM_DQM2 */
ldr r7, [r1, #0x318] /* DRAM_DQM3 */
stmfd r9!, {r4-r7}
ldr r4, [r1, #0x344] /* DRAM_SDQS0 */
ldr r5, [r1, #0x348] /* DRAM_SDQS1 */
ldr r6, [r1, #0x34c] /* DRAM_SDQS2 */
ldr r7, [r1, #0x350] /* DRAM_SDQS3 */
stmfd r9!, {r4-r7}
ldr r4, [r1, #0x5c4] /* GPR_B0DS */
ldr r5, [r1, #0x5cc] /* GPR_B1DS */
ldr r6, [r1, #0x5d4] /* GPR_B2DS */
ldr r7, [r1, #0x5d8] /* GPR_B3DS */
stmfd r9!, {r4-r7}
ldr r4, [r1, #0x300] /* DRAM_CAS */
ldr r5, [r1, #0x31c] /* DRAM_RAS */
ldr r6, [r1, #0x338] /* DRAM_SDCLK_0 */
ldr r7, [r1, #0x5ac] /* GPR_ADDS*/
stmfd r9!, {r4-r7}
ldr r4, [r1, #0x5b0] /* DDRMODE_CTL */
ldr r5, [r1, #0x5c0] /* DDRMODE */
ldr r6, [r1, #0x33c] /* DRAM_SODT0*/
ldr r7, [r1, #0x340] /* DRAM_SODT1*/
stmfd r9!, {r4-r7}
ldr r4, [r1, #0x330] /* DRAM_SDCKE0 */
ldr r5, [r1, #0x334] /* DRAM_SDCKE1 */
ldr r6, [r1, #0x320] /* DRAM_RESET */
ldr r7, [r1, #0x5c8] /* GPR_CTLDS */
stmfd r9!, {r4-r7}
.endm
.macro sl_ddr_io_restore
ldmea r9!, {r4-r7}
str r4, [r1, #0x30c] /* DRAM_DQM0 */
str r5, [r1, #0x310] /* DRAM_DQM1 */
str r6, [r1, #0x314] /* DRAM_DQM2 */
str r7, [r1, #0x318] /* DRAM_DQM3 */
ldmea r9!, {r4-r7}
str r4, [r1, #0x344] /* DRAM_SDQS0 */
str r5, [r1, #0x348] /* DRAM_SDQS1 */
str r6, [r1, #0x34c] /* DRAM_SDQS2 */
str r7, [r1, #0x350] /* DRAM_SDQS3 */
ldmea r9!, {r4-r7}
str r4, [r1, #0x5c4] /* GPR_B0DS */
str r5, [r1, #0x5cc] /* GPR_B1DS */
str r6, [r1, #0x5d4] /* GPR_B2DS */
str r7, [r1, #0x5d8] /* GPR_B3DS */
ldmea r9!, {r4-r7}
str r4, [r1, #0x300] /* DRAM_CAS */
str r5, [r1, #0x31c] /* DRAM_RAS */
str r6, [r1, #0x338] /* DRAM_SDCLK_0 */
str r7, [r1, #0x5ac] /* GPR_ADDS*/
ldmea r9!, {r4-r7}
str r4, [r1, #0x5b0] /* DDRMODE_CTL */
str r5, [r1, #0x5c0] /* DDRMODE */
str r6, [r1, #0x33c] /* DRAM_SODT0*/
str r7, [r1, #0x340] /* DRAM_SODT1*/
ldmea r9!, {r4-r7}
str r4, [r1, #0x330] /* DRAM_SDCKE0 */
str r5, [r1, #0x334] /* DRAM_SDCKE1 */
str r6, [r1, #0x320] /* DRAM_RESET */
str r7, [r1, #0x5c8] /* GPR_CTLDS */
.endm
.macro sl_ddr_io_set_lpm
mov r4, #0
str r4, [r1, #0x30c] /* DRAM_DQM0 */
str r4, [r1, #0x310] /* DRAM_DQM1 */
str r4, [r1, #0x314] /* DRAM_DQM2 */
str r4, [r1, #0x318] /* DRAM_DQM3 */
str r4, [r1, #0x344] /* DRAM_SDQS0 */
str r4, [r1, #0x348] /* DRAM_SDQS1 */
str r4, [r1, #0x34c] /* DRAM_SDQS2 */
str r4, [r1, #0x350] /* DRAM_SDQS3 */
str r4, [r1, #0x5c4] /* GPR_B0DS */
str r4, [r1, #0x5cc] /* GPR_B1DS */
str r4, [r1, #0x5d4] /* GPR_B2DS */
str r4, [r1, #0x5d8] /* GPR_B3DS */
str r4, [r1, #0x300] /* DRAM_CAS */
str r4, [r1, #0x31c] /* DRAM_RAS */
str r4, [r1, #0x338] /* DRAM_SDCLK_0 */
str r4, [r1, #0x5ac] /* GPR_ADDS*/
str r4, [r1, #0x5b0] /* DDRMODE_CTL */
str r4, [r1, #0x5c0] /* DDRMODE */
str r4, [r1, #0x33c] /* DRAM_SODT0*/
str r4, [r1, #0x340] /* DRAM_SODT1*/
str r4, [r1, #0x5c8] /* GPR_CTLDS */
mov r4, #0x80000
str r4, [r1, #0x320] /* DRAM_RESET */
mov r4, #0x1000
str r4, [r1, #0x330] /* DRAM_SDCKE0 */
str r4, [r1, #0x334] /* DRAM_SDCKE1 */
.endm
/*
* mx6sl_wait
*
* Idle the processor (eg, wait for interrupt).
* Make sure DDR is in self-refresh.
* IRQs are already disabled.
* r0 : arm_podf before WFI is entered
* r1: WFI IRAMcode base address.
*/
ENTRY(mx6sl_wait)
push {r4, r5, r6, r7, r8, r9, r10}
mx6sl_lpm_wfi:
/* Get the IRAM data storage address. */
mov r10, r1
mov r9, r1 /* get suspend_iram_base */
add r9, r9, #IRAM_WAIT_SIZE /* 4K */
ldr r1, =MX6Q_IOMUXC_BASE_ADDR
add r1, r1, #PERIPBASE_VIRT
/* Save the DDR IO state. */
sl_ddr_io_save
ldr r3, =ANATOP_BASE_ADDR
add r3, r3, #PERIPBASE_VIRT
ldr r2, =CCM_BASE_ADDR
add r2, r2, #PERIPBASE_VIRT
ldr r8, =MMDC_P0_BASE_ADDR
add r8, r8, #PERIPBASE_VIRT
/* Prime all TLB entries. */
adr r7, mx6sl_lpm_wfi @Address in this function.
ldr r6, [r7]
ldr r6, [r8]
ldr r6, [r3]
ldr r6, [r2]
ldr r6, [r1]
dsb
/* Disable Automatic power savings. */
ldr r6, [r8, #0x404]
orr r6, r6, #0x01
str r6, [r8, #0x404]
/* Make the DDR explicitly enter self-refresh. */
ldr r6, [r8, #0x404]
orr r6, r6, #0x200000
str r6, [r8, #0x404]
poll_dvfs_set_1:
ldr r6, [r8, #0x404]
and r6, r6, #0x2000000
cmp r6, #0x2000000
bne poll_dvfs_set_1
/* Now set DDR rate to 1MHz. */
/* DDR is from bypassed PLL2 on periph2_clk2 path.
* Set the periph2_clk2_podf to divide by 8.
*/
ldr r6, [r2, #0x14]
orr r6, r6, #0x07
str r6, [r2, #0x14]
/* Now set MMDC PODF to divide by 3. */
ldr r6, [r2, #0x14]
bic r6, r6, #0x38
orr r6, r6, #0x10
str r6, [r2, #0x14]
/* Set the DDR IO in LPM state. */
sl_ddr_io_set_lpm
/* Set AHB to 8MHz., AXI to 3MHz */
/* We want to ensure IPG_PERCLK to AHB
* clk ratio is 1:2.5
*/
/* Store the AXI/AHB podfs. */
ldr r9, [r2, #0x14]
mov r6, r9
bic r6, r6, #0x1c00
orr r6, r6, #0x800
orr r6, r6, #0x70000
str r6, [r2, #0x14]
/* Loop till podf is accepted. */
ahb_podf:
ldr r6, [r2, #0x48]
cmp r6, #0x0
bne podf_loop
/* Now set ARM to 24MHz. */
/* Move ARM to be sourced from STEP_CLK
* after setting STEP_CLK to 24MHz.
*/
ldr r6, [r2, #0xc]
bic r6, r6, #0x100
str r6, [r2, #0x0c]
/* Now PLL1_SW_CLK to step_clk. */
ldr r6, [r2, #0x0c]
orr r6, r6, #0x4
str r6, [r2, #0x0c]
/* Bypass PLL1 and power it down. */
ldr r6, =(1 << 16)
orr r6, r6, #0x1000
str r6, [r3, #0x04]
/* Set the ARM PODF to divide by 8. */
/* IPG is at 4MHz here, we need ARM to
* run at the 12:5 ratio (WAIT mode issue).
*/
ldr r6, =0x7
str r6, [r2, #0x10]
/* Loop till podf is accepted. */
podf_loop:
ldr r6, [r2, #0x48]
cmp r6, #0x0
bne podf_loop
/* Now do WFI. */
dsb
wfi
/* Set original ARM PODF back. */
str r0, [r2, #0x10]
/* Loop till podf is accepted. */
podf_loop1:
ldr r6, [r2, #0x48]
cmp r6, #0x0
bne podf_loop1
/* Power up PLL1 and un-bypass it. */
ldr r6, =(1 << 12)
str r6, [r3, #0x08]
/* Wait for PLL1 to relock. */
wait_for_pll_lock:
ldr r6, [r3, #0x0]
and r6, r6, #0x80000000
cmp r6, #0x80000000
bne wait_for_pll_lock
ldr r6, =(1 << 16)
str r6, [r3, #0x08]
/* Set PLL1_sw_clk back to PLL1. */
ldr r6, [r2, #0x0c]
bic r6, r6, #0x4
str r6, [r2, #0xc]
/* Restore AHB/AXI back. */
str r9, [r2, #0x14]
/* Loop till podf is accepted. */
ahb_podf1:
ldr r6, [r2, #0x48]
cmp r6, #0x0
bne podf_loop1
mov r9, r10 /* get suspend_iram_base */
add r9, r9, #IRAM_WAIT_SIZE /* 4K */
/* Restore the DDR IO before exiting self-refresh. */
sl_ddr_io_restore
/* Set MMDC back to 24MHz. */
/* Set periph2_clk2_podf to divide by 1. */
/* Now set MMDC PODF to divide by 1. */
ldr r6, [r2, #0x14]
bic r6, r6, #0x3f
str r6, [r2, #0x14]
/* clear DVFS - exit from self refresh mode */
ldr r6, [r8, #0x404]
bic r6, r6, #0x200000
str r6, [r8, #0x404]
poll_dvfs_clear_1:
ldr r6, [r8, #0x404]
and r6, r6, #0x2000000
cmp r6, #0x2000000
beq poll_dvfs_clear_1
/* Enable Automatic power savings. */
ldr r6, [r8, #0x404]
bic r6, r6, #0x01
str r6, [r8, #0x404]
pop {r4,r5, r6, r7, r8, r9, r10}
/* Restore registers */
mov pc, lr
.type mx6sl_do_wait, #object
ENTRY(mx6sl_do_wait)
.word mx6sl_wait
.size mx6sl_wait, . - mx6sl_wait
......@@ -57,9 +57,10 @@ volatile unsigned int num_cpu_idle;
volatile unsigned int num_cpu_idle_lock = 0x0;
int wait_mode_arm_podf;
int cur_arm_podf;
bool arm_mem_clked_in_wait;
void arch_idle_with_workaround(int cpu);
extern void *mx6sl_wfi_iram_base;
extern void (*mx6sl_wfi_iram)(int arm_podf, unsigned long wfi_iram_addr);
extern void mx6_wait(void *num_cpu_idle_lock, void *num_cpu_idle, \
int wait_arm_podf, int cur_arm_podf);
extern bool enable_wait_mode;
......@@ -78,6 +79,7 @@ void gpc_set_wakeup(unsigned int irq[4])
return;
}
/* set cpu low power mode before WFI instruction */
void mxc_cpu_lp_set(enum mxc_cpu_pwr_mode mode)
{
......@@ -251,25 +253,34 @@ void arch_idle_single_core(void)
ca9_do_idle();
} else {
/*
* Implement the 12:5 ARM:IPG_CLK ratio
* workaround for the WAIT mode issue.
* We can directly use the divider to drop the ARM
* core freq in a single core environment.
* Set the ARM_PODF to get the max freq possible
* to avoid the WAIT mode issue when IPG is at 66MHz.
*/
if (cpu_is_mx6sl()) {
reg = __raw_readl(MXC_CCM_CGPR);
reg |= MXC_CCM_CGPR_MEM_IPG_STOP_MASK;
__raw_writel(reg, MXC_CCM_CGPR);
}
__raw_writel(wait_mode_arm_podf, MXC_CCM_CACRR);
while (__raw_readl(MXC_CCM_CDHIPR))
;
ca9_do_idle();
if (low_bus_freq_mode && cpu_is_mx6sl()) {
u32 org_arm_podf = __raw_readl(MXC_CCM_CACRR);
__raw_writel(cur_arm_podf - 1, MXC_CCM_CACRR);
/* Need to run WFI code from IRAM so that
* we can lower DDR freq.
*/
mx6sl_wfi_iram(org_arm_podf,
(unsigned long)mx6sl_wfi_iram_base);
/* Clear the chicken bit to allow memories
* to be powered down
*/
} else {
/*
* Implement the 12:5 ARM:IPG_CLK ratio
* workaround for the WAIT mode issue.
* We can directly use the divider to drop the ARM
* core freq in a single core environment.
* Set the ARM_PODF to get the max freq possible
* to avoid the WAIT mode issue when IPG is at 66MHz.
*/
__raw_writel(wait_mode_arm_podf, MXC_CCM_CACRR);
while (__raw_readl(MXC_CCM_CDHIPR))
;
ca9_do_idle();
__raw_writel(cur_arm_podf - 1, MXC_CCM_CACRR);
}
}
}
......@@ -331,7 +342,7 @@ void arch_idle(void)
{
if (enable_wait_mode) {
mxc_cpu_lp_set(WAIT_UNCLOCKED_POWER_OFF);
if ((mem_clk_on_in_wait || arm_mem_clked_in_wait)) {
if (mem_clk_on_in_wait) {
u32 reg;
/*
* MX6SL, MX6Q (TO1.2 or later) and
......
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