[PATCH v2 4/4] soc bcm: brcmstb: Add support for S2/S3/S5 suspend states (MIPS)

Florian Fainelli
2017-06-26T22:32:48Z

From: Justin Chen <justinpopo6@gmail.com>

This commit adds support for the Broadcom STB S2/S3/S5 suspend
states on MIPS based SoCs.

This requires quite a lot of code in order to deal with the
different HW blocks that need to be quiesced during suspend:

- DDR PHY
- DDR memory controller and arbiter
- control processor

The final steps of the suspend execute in cache and there is is a little
bit of assembly code in order to shut down the DDR PHY PLL and then go
into a wait loop until a wake-up even occurs. Conversely the resume part
involves waiting for the DDR PHY PLL to come back up and resume
executions where we left.

Signed-off-by: Justin Chen <justinpopo6@gmail.com>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
---
drivers/soc/bcm/brcmstb/Kconfig | 2 +-
drivers/soc/bcm/brcmstb/pm/Makefile | 1 +
drivers/soc/bcm/brcmstb/pm/pm-mips.c | 461 +++++++++++++++++++++++++++++++++++
drivers/soc/bcm/brcmstb/pm/pm.h | 13 +-
drivers/soc/bcm/brcmstb/pm/s2-mips.S | 200 +++++++++++++++
drivers/soc/bcm/brcmstb/pm/s3-mips.S | 146 +++++++++++
6 files changed, 821 insertions(+), 2 deletions(-)
create mode 100644 drivers/soc/bcm/brcmstb/pm/pm-mips.c
create mode 100644 drivers/soc/bcm/brcmstb/pm/s2-mips.S
create mode 100644 drivers/soc/bcm/brcmstb/pm/s3-mips.S

diff --git a/drivers/soc/bcm/brcmstb/Kconfig b/drivers/soc/bcm/brcmstb/Kconfig
index 9b1cc7f86ea2..d05bfce82e71 100644
--- a/drivers/soc/bcm/brcmstb/Kconfig
+++ b/drivers/soc/bcm/brcmstb/Kconfig
@@ -4,6 +4,6 @@ config BRCMSTB_PM
bool "Support suspend/resume for STB platforms"
default y
depends on PM
- depends on ARM
+ depends on ARM || BMIPS_GENERIC

endif # SOC_BRCMSTB
diff --git a/drivers/soc/bcm/brcmstb/pm/Makefile b/drivers/soc/bcm/brcmstb/pm/Makefile
index 7c3d20135b7c..08bbd244ef11 100644
--- a/drivers/soc/bcm/brcmstb/pm/Makefile
+++ b/drivers/soc/bcm/brcmstb/pm/Makefile
@@ -1,2 +1,3 @@
obj-$(CONFIG_ARM) += s2-arm.o pm-arm.o
AFLAGS_s2-arm.o := -march=armv7-a
+obj-$(CONFIG_BMIPS_GENERIC) += s2-mips.o s3-mips.o pm-mips.o
diff --git a/drivers/soc/bcm/brcmstb/pm/pm-mips.c b/drivers/soc/bcm/brcmstb/pm/pm-mips.c
new file mode 100644
index 000000000000..9300b5f62e56
--- /dev/null
+++ b/drivers/soc/bcm/brcmstb/pm/pm-mips.c
@@ -0,0 +1,461 @@
+/*
+ * MIPS-specific support for Broadcom STB S2/S3/S5 power management
+ *
+ * Copyright (C) 2016-2017 Broadcom
+ *
+ * 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.
+ */
+
+#include <linux/kernel.h>
+#include <linux/printk.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/delay.h>
+#include <linux/suspend.h>
+#include <asm/bmips.h>
+#include <asm/tlbflush.h>
+
+#include "pm.h"
+
+#define S2_NUM_PARAMS 6
+#define MAX_NUM_MEMC 3
+
+/* S3 constants */
+#define MAX_GP_REGS 16
+#define MAX_CP0_REGS 32
+#define NUM_MEMC_CLIENTS 128
+#define AON_CTRL_RAM_SIZE 128
+#define BRCMSTB_S3_MAGIC 0x5AFEB007
+
+#define CLEAR_RESET_MASK 0x01
+
+/* Index each CP0 register that needs to be saved */
+#define CONTEXT 0
+#define USER_LOCAL 1
+#define PGMK 2
+#define HWRENA 3
+#define COMPARE 4
+#define STATUS 5
+#define CONFIG 6
+#define MODE 7
+#define EDSP 8
+#define BOOT_VEC 9
+#define EBASE 10
+
+struct brcmstb_memc {
+ void __iomem *ddr_phy_base;
+ void __iomem *arb_base;
+};
+
+struct brcmstb_pm_control {
+ void __iomem *aon_ctrl_base;
+ void __iomem *aon_sram_base;
+ void __iomem *timers_base;
+ struct brcmstb_memc memcs[MAX_NUM_MEMC];
+ int num_memc;
+};
+
+struct brcm_pm_s3_context {
+ u32 cp0_regs[MAX_CP0_REGS];
+ u32 memc0_rts[NUM_MEMC_CLIENTS];
+ u32 sc_boot_vec;
+};
+
+struct brcmstb_mem_transfer;
+
+struct brcmstb_mem_transfer {
+ struct brcmstb_mem_transfer *next;
+ void *src;
+ void *dst;
+ dma_addr_t pa_src;
+ dma_addr_t pa_dst;
+ u32 len;
+ u8 key;
+ u8 mode;
+ u8 src_remapped;
+ u8 dst_remapped;
+ u8 src_dst_remapped;
+};
+
+#define AON_SAVE_SRAM(base, idx, val) \
+ __raw_writel(val, base + (idx << 2))
+
+/* Used for saving registers in asm */
+u32 gp_regs[MAX_GP_REGS];
+
+#define BSP_CLOCK_STOP 0x00
+#define PM_INITIATE 0x01
+
+static struct brcmstb_pm_control ctrl;
+
+static void brcm_pm_save_cp0_context(struct brcm_pm_s3_context *ctx)
+{
+ /* Generic MIPS */
+ ctx->cp0_regs[CONTEXT] = read_c0_context();
+ ctx->cp0_regs[USER_LOCAL] = read_c0_userlocal();
+ ctx->cp0_regs[PGMK] = read_c0_pagemask();
+ ctx->cp0_regs[HWRENA] = read_c0_cache();
+ ctx->cp0_regs[COMPARE] = read_c0_compare();
+ ctx->cp0_regs[STATUS] = read_c0_status();
+
+ /* Broadcom specific */
+ ctx->cp0_regs[CONFIG] = read_c0_brcm_config();
+ ctx->cp0_regs[MODE] = read_c0_brcm_mode();
+ ctx->cp0_regs[EDSP] = read_c0_brcm_edsp();
+ ctx->cp0_regs[BOOT_VEC] = read_c0_brcm_bootvec();
+ ctx->cp0_regs[EBASE] = read_c0_ebase();
+
+ ctx->sc_boot_vec = bmips_read_zscm_reg(0xa0);
+}
+
+static void brcm_pm_restore_cp0_context(struct brcm_pm_s3_context *ctx)
+{
+ /* Restore cp0 state */
+ bmips_write_zscm_reg(0xa0, ctx->sc_boot_vec);
+
+ /* Generic MIPS */
+ write_c0_context(ctx->cp0_regs[CONTEXT]);
+ write_c0_userlocal(ctx->cp0_regs[USER_LOCAL]);
+ write_c0_pagemask(ctx->cp0_regs[PGMK]);
+ write_c0_cache(ctx->cp0_regs[HWRENA]);
+ write_c0_compare(ctx->cp0_regs[COMPARE]);
+ write_c0_status(ctx->cp0_regs[STATUS]);
+
+ /* Broadcom specific */
+ write_c0_brcm_config(ctx->cp0_regs[CONFIG]);
+ write_c0_brcm_mode(ctx->cp0_regs[MODE]);
+ write_c0_brcm_edsp(ctx->cp0_regs[EDSP]);
+ write_c0_brcm_bootvec(ctx->cp0_regs[BOOT_VEC]);
+ write_c0_ebase(ctx->cp0_regs[EBASE]);
+}
+
+static void brcmstb_pm_handshake(void)
+{
+ void __iomem *base = ctrl.aon_ctrl_base;
+ u32 tmp;
+
+ /* BSP power handshake, v1 */
+ tmp = __raw_readl(base + AON_CTRL_HOST_MISC_CMDS);
+ tmp &= ~1UL;
+ __raw_writel(tmp, base + AON_CTRL_HOST_MISC_CMDS);
+ (void)__raw_readl(base + AON_CTRL_HOST_MISC_CMDS);
+
+ __raw_writel(0, base + AON_CTRL_PM_INITIATE);
+ (void)__raw_readl(base + AON_CTRL_PM_INITIATE);
+ __raw_writel(BSP_CLOCK_STOP | PM_INITIATE,
+ base + AON_CTRL_PM_INITIATE);
+ /*
+ * HACK: BSP may have internal race on the CLOCK_STOP command.
+ * Avoid touching the BSP for a few milliseconds.
+ */
+ mdelay(3);
+}
+
+static void brcmstb_pm_s5(void)
+{
+ void __iomem *base = ctrl.aon_ctrl_base;
+
+ brcmstb_pm_handshake();
+
+ /* Clear magic s3 warm-boot value */
+ AON_SAVE_SRAM(ctrl.aon_sram_base, 0, 0);
+
+ /* Set the countdown */
+ __raw_writel(0x10, base + AON_CTRL_PM_CPU_WAIT_COUNT);
+ (void)__raw_readl(base + AON_CTRL_PM_CPU_WAIT_COUNT);
+
+ /* Prepare to S5 cold boot */
+ __raw_writel(PM_COLD_CONFIG, base + AON_CTRL_PM_CTRL);
+ (void)__raw_readl(base + AON_CTRL_PM_CTRL);
+
+ __raw_writel((PM_COLD_CONFIG | PM_PWR_DOWN), base +
+ AON_CTRL_PM_CTRL);
+ (void)__raw_readl(base + AON_CTRL_PM_CTRL);
+
+ __asm__ __volatile__(
+ " wait\n"
+ : : : "memory");
+}
+
+static int brcmstb_pm_s3(void)
+{
+ struct brcm_pm_s3_context s3_context;
+ void __iomem *memc_arb_base;
+ unsigned long flags;
+ u32 tmp;
+ int i;
+
+ /* Prepare for s3 */
+ AON_SAVE_SRAM(ctrl.aon_sram_base, 0, BRCMSTB_S3_MAGIC);
+ AON_SAVE_SRAM(ctrl.aon_sram_base, 1, (u32)&s3_reentry);
+ AON_SAVE_SRAM(ctrl.aon_sram_base, 2, 0);
+
+ /* Clear RESET_HISTORY */
+ tmp = __raw_readl(ctrl.aon_ctrl_base + AON_CTRL_RESET_CTRL);
+ tmp &= ~CLEAR_RESET_MASK;
+ __raw_writel(tmp, ctrl.aon_ctrl_base + AON_CTRL_RESET_CTRL);
+
+ local_irq_save(flags);
+
+ /* Inhibit DDR_RSTb pulse for both MMCs*/
+ for (i = 0; i < ctrl.num_memc; i++) {
+ tmp = __raw_readl(ctrl.memcs[i].ddr_phy_base +
+ DDR40_PHY_CONTROL_REGS_0_STANDBY_CTRL);
+
+ tmp &= ~0x0f;
+ __raw_writel(tmp, ctrl.memcs[i].ddr_phy_base +
+ DDR40_PHY_CONTROL_REGS_0_STANDBY_CTRL);
+ tmp |= (0x05 | BIT(5));
+ __raw_writel(tmp, ctrl.memcs[i].ddr_phy_base +
+ DDR40_PHY_CONTROL_REGS_0_STANDBY_CTRL);
+ }
+
+ /* Save CP0 context */
+ brcm_pm_save_cp0_context(&s3_context);
+
+ /* Save RTS(skip debug register) */
+ memc_arb_base = ctrl.memcs[0].arb_base + 4;
+ for (i = 0; i < NUM_MEMC_CLIENTS; i++) {
+ s3_context.memc0_rts[i] = __raw_readl(memc_arb_base);
+ memc_arb_base += 4;
+ }
+
+ /* Save I/O context */
+ local_flush_tlb_all();
+ _dma_cache_wback_inv(0, ~0);
+
+ brcm_pm_do_s3(ctrl.aon_ctrl_base, current_cpu_data.dcache.linesz);
+
+ /* CPU reconfiguration */
+ local_flush_tlb_all();
+ bmips_cpu_setup();
+ cpumask_clear(&bmips_booted_mask);
+
+ /* Restore RTS (skip debug register) */
+ memc_arb_base = ctrl.memcs[0].arb_base + 4;
+ for (i = 0; i < NUM_MEMC_CLIENTS; i++) {
+ __raw_writel(s3_context.memc0_rts[i], memc_arb_base);
+ memc_arb_base += 4;
+ }
+
+ /* restore CP0 context */
+ brcm_pm_restore_cp0_context(&s3_context);
+
+ local_irq_restore(flags);
+
+ return 0;
+}
+
+static int brcmstb_pm_s2(void)
+{
+ /*
+ * We need to pass 6 arguments to an assembly function. Lets avoid the
+ * stack and pass arguments in a explicit 4 byte array. The assembly
+ * code assumes all arguments are 4 bytes and arguments are ordered
+ * like so:
+ *
+ * 0: AON_CTRl base register
+ * 1: DDR_PHY base register
+ * 2: TIMERS base resgister
+ * 3: I-Cache line size
+ * 4: Restart vector address
+ * 5: Restart vector size
+ */
+ u32 s2_params[6];
+
+ /* Prepare s2 parameters */
+ s2_params[0] = (u32)ctrl.aon_ctrl_base;
+ s2_params[1] = (u32)ctrl.memcs[0].ddr_phy_base;
+ s2_params[2] = (u32)ctrl.timers_base;
+ s2_params[3] = (u32)current_cpu_data.icache.linesz;
+ s2_params[4] = (u32)BMIPS_WARM_RESTART_VEC;
+ s2_params[5] = (u32)(bmips_smp_int_vec_end -
+ bmips_smp_int_vec);
+
+ /* Drop to standby */
+ brcm_pm_do_s2(s2_params);
+
+ return 0;
+}
+
+static int brcmstb_pm_standby(bool deep_standby)
+{
+ brcmstb_pm_handshake();
+
+ /* Send IRQs to BMIPS_WARM_RESTART_VEC */
+ clear_c0_cause(CAUSEF_IV);
+ irq_disable_hazard();
+ set_c0_status(ST0_BEV);
+ irq_disable_hazard();
+
+ if (deep_standby)
+ brcmstb_pm_s3();
+ else
+ brcmstb_pm_s2();
+
+ /* Send IRQs to normal runtime vectors */
+ clear_c0_status(ST0_BEV);
+ irq_disable_hazard();
+ set_c0_cause(CAUSEF_IV);
+ irq_disable_hazard();
+
+ return 0;
+}
+
+static int brcmstb_pm_enter(suspend_state_t state)
+{
+ int ret = -EINVAL;
+
+ switch (state) {
+ case PM_SUSPEND_STANDBY:
+ ret = brcmstb_pm_standby(false);
+ break;
+ case PM_SUSPEND_MEM:
+ ret = brcmstb_pm_standby(true);
+ break;
+ }
+
+ return ret;
+}
+
+static int brcmstb_pm_valid(suspend_state_t state)
+{
+ switch (state) {
+ case PM_SUSPEND_STANDBY:
+ return true;
+ case PM_SUSPEND_MEM:
+ return true;
+ default:
+ return false;
+ }
+}
+
+static const struct platform_suspend_ops brcmstb_pm_ops = {
+ .enter = brcmstb_pm_enter,
+ .valid = brcmstb_pm_valid,
+};
+
+static const struct of_device_id aon_ctrl_dt_ids[] = {
+ { .compatible = "brcm,brcmstb-aon-ctrl" },
+ { /* sentinel */ }
+};
+
+static const struct of_device_id ddr_phy_dt_ids[] = {
+ { .compatible = "brcm,brcmstb-ddr-phy" },
+ { /* sentinel */ }
+};
+
+static const struct of_device_id arb_dt_ids[] = {
+ { .compatible = "brcm,brcmstb-memc-arb" },
+ { /* sentinel */ }
+};
+
+static const struct of_device_id timers_ids[] = {
+ { .compatible = "brcm,brcmstb-timers" },
+ { /* sentinel */ }
+};
+
+static inline void __iomem *brcmstb_ioremap_node(struct device_node *dn,
+ int index)
+{
+ return of_io_request_and_map(dn, index, dn->full_name);
+}
+
+static void __iomem *brcmstb_ioremap_match(const struct of_device_id *matches,
+ int index, const void **ofdata)
+{
+ struct device_node *dn;
+ const struct of_device_id *match;
+
+ dn = of_find_matching_node_and_match(NULL, matches, &match);
+ if (!dn)
+ return ERR_PTR(-EINVAL);
+
+ if (ofdata)
+ *ofdata = match->data;
+
+ return brcmstb_ioremap_node(dn, index);
+}
+
+static int brcmstb_pm_init(void)
+{
+ struct device_node *dn;
+ void __iomem *base;
+ int i;
+
+ /* AON ctrl registers */
+ base = brcmstb_ioremap_match(aon_ctrl_dt_ids, 0, NULL);
+ if (IS_ERR(base)) {
+ pr_err("error mapping AON_CTRL\n");
+ goto aon_err;
+ }
+ ctrl.aon_ctrl_base = base;
+
+ /* AON SRAM registers */
+ base = brcmstb_ioremap_match(aon_ctrl_dt_ids, 1, NULL);
+ if (IS_ERR(base)) {
+ pr_err("error mapping AON_SRAM\n");
+ goto sram_err;
+ }
+ ctrl.aon_sram_base = base;
+
+ ctrl.num_memc = 0;
+ /* Map MEMC DDR PHY registers */
+ for_each_matching_node(dn, ddr_phy_dt_ids) {
+ i = ctrl.num_memc;
+ if (i >= MAX_NUM_MEMC) {
+ pr_warn("Too many MEMCs (max %d)\n", MAX_NUM_MEMC);
+ break;
+ }
+ base = brcmstb_ioremap_node(dn, 0);
+ if (IS_ERR(base))
+ goto ddr_err;
+
+ ctrl.memcs[i].ddr_phy_base = base;
+ ctrl.num_memc++;
+ }
+
+ /* MEMC ARB registers */
+ base = brcmstb_ioremap_match(arb_dt_ids, 0, NULL);
+ if (IS_ERR(base)) {
+ pr_err("error mapping MEMC ARB\n");
+ goto ddr_err;
+ }
+ ctrl.memcs[0].arb_base = base;
+
+ /* Timer registers */
+ base = brcmstb_ioremap_match(timers_ids, 0, NULL);
+ if (IS_ERR(base)) {
+ pr_err("error mapping timers\n");
+ goto tmr_err;
+ }
+ ctrl.timers_base = base;
+
+ /* s3 cold boot aka s5 */
+ pm_power_off = brcmstb_pm_s5;
+
+ suspend_set_ops(&brcmstb_pm_ops);
+
+ return 0;
+
+tmr_err:
+ iounmap(ctrl.memcs[0].arb_base);
+ddr_err:
+ for (i = 0; i < ctrl.num_memc; i++)
+ iounmap(ctrl.memcs[i].ddr_phy_base);
+
+ iounmap(ctrl.aon_sram_base);
+sram_err:
+ iounmap(ctrl.aon_ctrl_base);
+aon_err:
+ return PTR_ERR(base);
+}
+arch_initcall(brcmstb_pm_init);
diff --git a/drivers/soc/bcm/brcmstb/pm/pm.h b/drivers/soc/bcm/brcmstb/pm/pm.h
index 142519fdb8f8..b7d35ac70e60 100644
--- a/drivers/soc/bcm/brcmstb/pm/pm.h
+++ b/drivers/soc/bcm/brcmstb/pm/pm.h
@@ -70,9 +70,20 @@

#ifndef __ASSEMBLY__

+#ifndef CONFIG_MIPS
extern const unsigned long brcmstb_pm_do_s2_sz;
extern asmlinkage int brcmstb_pm_do_s2(void __iomem *aon_ctrl_base,
void __iomem *ddr_phy_pll_status);
-#endif
+#else
+/* s2 asm */
+extern asmlinkage int brcm_pm_do_s2(u32 *s2_params);
+
+/* s3 asm */
+extern asmlinkage int brcm_pm_do_s3(void __iomem *aon_ctrl_base,
+ int dcache_linesz);
+extern int s3_reentry;
+#endif /* CONFIG_MIPS */
+
+#endif

#endif /* __BRCMSTB_PM_H__ */
diff --git a/drivers/soc/bcm/brcmstb/pm/s2-mips.S b/drivers/soc/bcm/brcmstb/pm/s2-mips.S
new file mode 100644
index 000000000000..27a14bc46043
--- /dev/null
+++ b/drivers/soc/bcm/brcmstb/pm/s2-mips.S
@@ -0,0 +1,200 @@
+/*
+ * Copyright (C) 2016 Broadcom Corporation
+ *
+ * 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.
+ */
+
+#include <asm/asm.h>
+#include <asm/regdef.h>
+#include <asm/mipsregs.h>
+#include <asm/stackframe.h>
+
+#include "pm.h"
+
+ .text
+ .set noreorder
+ .align 5
+
+/*
+ * a0: u32 params array
+ */
+LEAF(brcm_pm_do_s2)
+
+ subu sp, 64
+ sw ra, 0(sp)
+ sw s0, 4(sp)
+ sw s1, 8(sp)
+ sw s2, 12(sp)
+ sw s3, 16(sp)
+ sw s4, 20(sp)
+ sw s5, 24(sp)
+ sw s6, 28(sp)
+ sw s7, 32(sp)
+
+ /*
+ * Dereference the params array
+ * s0: AON_CTRL base register
+ * s1: DDR_PHY base register
+ * s2: TIMERS base register
+ * s3: I-Cache line size
+ * s4: Restart vector address
+ * s5: Restart vector size
+ */
+ move t0, a0
+
+ lw s0, 0(t0)
+ lw s1, 4(t0)
+ lw s2, 8(t0)
+ lw s3, 12(t0)
+ lw s4, 16(t0)
+ lw s5, 20(t0)
+
+ /* Lock this asm section into the I-cache */
+ addiu t1, s3, -1
+ not t1
+
+ la t0, brcm_pm_do_s2
+ and t0, t1
+
+ la t2, asm_end
+ and t2, t1
+
+1: cache 0x1c, 0(t0)
+ bne t0, t2, 1b
+ addu t0, s3
+
+ /* Lock the interrupt vector into the I-cache */
+ move t0, zero
+
+2: move t1, s4
+ cache 0x1c, 0(t1)
+ addu t1, s3
+ addu t0, s3
+ ble t0, s5, 2b
+ nop
+
+ sync
+
+ /* Power down request */
+ li t0, PM_S2_COMMAND
+ sw zero, AON_CTRL_PM_CTRL(s0)
+ lw zero, AON_CTRL_PM_CTRL(s0)
+ sw t0, AON_CTRL_PM_CTRL(s0)
+ lw t0, AON_CTRL_PM_CTRL(s0)
+
+ /* Enable CP0 interrupt 2 and wait for interrupt */
+ mfc0 t0, CP0_STATUS
+ /* Save cp0 sr for restoring later */
+ move s6, t0
+
+ li t1, ~(ST0_IM | ST0_IE)
+ and t0, t1
+ ori t0, STATUSF_IP2
+ mtc0 t0, CP0_STATUS
+ nop
+ nop
+ nop
+ ori t0, ST0_IE
+ mtc0 t0, CP0_STATUS
+
+ /* Wait for interrupt */
+ wait
+ nop
+
+ /* Wait for memc0 */
+1: lw t0, DDR40_PHY_CONTROL_REGS_0_PLL_STATUS(s1)
+ andi t0, 1
+ beqz t0, 1b
+ nop
+
+ /* 1ms delay needed for stable recovery */
+ /* Use TIMER1 to count 1 ms */
+ li t0, RESET_TIMER
+ sw t0, TIMER_TIMER1_CTRL(s2)
+ lw t0, TIMER_TIMER1_CTRL(s2)
+
+ li t0, START_TIMER
+ sw t0, TIMER_TIMER1_CTRL(s2)
+ lw t0, TIMER_TIMER1_CTRL(s2)
+
+ /* Prepare delay */
+ li t0, TIMER_MASK
+ lw t1, TIMER_TIMER1_STAT(s2)
+ and t1, t0
+ /* 1ms delay */
+ addi t1, 27000
+
+ /* Wait for the timer value to exceed t1 */
+1: lw t0, TIMER_TIMER1_STAT(s2)
+ sgtu t2, t1, t0
+ bnez t2, 1b
+ nop
+
+ /* Power back up */
+ li t1, 1
+ sw t1, AON_CTRL_HOST_MISC_CMDS(s0)
+ lw t1, AON_CTRL_HOST_MISC_CMDS(s0)
+
+ sw zero, AON_CTRL_PM_CTRL(s0)
+ lw zero, AON_CTRL_PM_CTRL(s0)
+
+ /* Unlock I-cache */
+ addiu t1, s3, -1
+ not t1
+
+ la t0, brcm_pm_do_s2
+ and t0, t1
+
+ la t2, asm_end
+ and t2, t1
+
+1: cache 0x00, 0(t0)
+ bne t0, t2, 1b
+ addu t0, s3
+
+ /* Unlock interrupt vector */
+ move t0, zero
+
+2: move t1, s4
+ cache 0x00, 0(t1)
+ addu t1, s3
+ addu t0, s3
+ ble t0, s5, 2b
+ nop
+
+ /* Restore cp0 sr */
+ sync
+ nop
+ mtc0 s6, CP0_STATUS
+ nop
+
+ /* Set return value to success */
+ li v0, 0
+
+ /* Return to caller */
+ lw s7, 32(sp)
+ lw s6, 28(sp)
+ lw s5, 24(sp)
+ lw s4, 20(sp)
+ lw s3, 16(sp)
+ lw s2, 12(sp)
+ lw s1, 8(sp)
+ lw s0, 4(sp)
+ lw ra, 0(sp)
+ addiu sp, 64
+
+ jr ra
+ nop
+END(brcm_pm_do_s2)
+
+ .globl asm_end
+asm_end:
+ nop
+
diff --git a/drivers/soc/bcm/brcmstb/pm/s3-mips.S b/drivers/soc/bcm/brcmstb/pm/s3-mips.S
new file mode 100644
index 000000000000..1242308a8868
--- /dev/null
+++ b/drivers/soc/bcm/brcmstb/pm/s3-mips.S
@@ -0,0 +1,146 @@
+/*
+ * Copyright (C) 2016 Broadcom Corporation
+ *
+ * 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.
+ */
+
+#include <asm/asm.h>
+#include <asm/regdef.h>
+#include <asm/mipsregs.h>
+#include <asm/bmips.h>
+
+#include "pm.h"
+
+ .text
+ .set noreorder
+ .align 5
+ .global s3_reentry
+
+/*
+ * a0: AON_CTRL base register
+ * a1: D-Cache line size
+ */
+LEAF(brcm_pm_do_s3)
+
+ /* Get the address of s3_context */
+ la t0, gp_regs
+ sw ra, 0(t0)
+ sw s0, 4(t0)
+ sw s1, 8(t0)
+ sw s2, 12(t0)
+ sw s3, 16(t0)
+ sw s4, 20(t0)
+ sw s5, 24(t0)
+ sw s6, 28(t0)
+ sw s7, 32(t0)
+ sw gp, 36(t0)
+ sw sp, 40(t0)
+ sw fp, 44(t0)
+
+ /* Save CP0 Status */
+ mfc0 t1, CP0_STATUS
+ sw t1, 48(t0)
+
+ /* Write-back gp registers - cache will be gone */
+ addiu t1, a1, -1
+ not t1
+ and t0, t1
+
+ /* Flush at least 64 bytes */
+ addiu t2, t0, 64
+ and t2, t1
+
+1: cache 0x17, 0(t0)
+ bne t0, t2, 1b
+ addu t0, a1
+
+ /* Drop to deep standby */
+ li t1, PM_WARM_CONFIG
+ sw zero, AON_CTRL_PM_CTRL(a0)
+ lw zero, AON_CTRL_PM_CTRL(a0)
+ sw t1, AON_CTRL_PM_CTRL(a0)
+ lw t1, AON_CTRL_PM_CTRL(a0)
+
+ li t1, (PM_WARM_CONFIG | PM_PWR_DOWN)
+ sw t1, AON_CTRL_PM_CTRL(a0)
+ lw t1, AON_CTRL_PM_CTRL(a0)
+
+ /* Enable CP0 interrupt 2 and wait for interrupt */
+ mfc0 t0, CP0_STATUS
+
+ li t1, ~(ST0_IM | ST0_IE)
+ and t0, t1
+ ori t0, STATUSF_IP2
+ mtc0 t0, CP0_STATUS
+ nop
+ nop
+ nop
+ ori t0, ST0_IE
+ mtc0 t0, CP0_STATUS
+
+ /* Wait for interrupt */
+ wait
+ nop
+
+s3_reentry:
+
+ /* Clear call/return stack */
+ li t0, (0x06 << 16)
+ mtc0 t0, $22, 2
+ ssnop
+ ssnop
+ ssnop
+
+ /* Clear jump target buffer */
+ li t0, (0x04 << 16)
+ mtc0 t0, $22, 2
+ ssnop
+ ssnop
+ ssnop
+
+ sync
+ nop
+
+ /* Setup mmu defaults */
+ mtc0 zero, CP0_WIRED
+ mtc0 zero, CP0_ENTRYHI
+ li k0, PM_DEFAULT_MASK
+ mtc0 k0, CP0_PAGEMASK
+
+ li sp, BMIPS_WARM_RESTART_VEC
+ la k0, plat_wired_tlb_setup
+ jalr k0
+ nop
+
+ /* Restore general purpose registers */
+ la t0, gp_regs
+ lw fp, 44(t0)
+ lw sp, 40(t0)
+ lw gp, 36(t0)
+ lw s7, 32(t0)
+ lw s6, 28(t0)
+ lw s5, 24(t0)
+ lw s4, 20(t0)
+ lw s3, 16(t0)
+ lw s2, 12(t0)
+ lw s1, 8(t0)
+ lw s0, 4(t0)
+ lw ra, 0(t0)
+
+ /* Restore CP0 status */
+ lw t1, 48(t0)
+ mtc0 t1, CP0_STATUS
+
+ /* Return to caller */
+ li v0, 0
+ jr ra
+ nop
+
+END(brcm_pm_do_s3)
--
2.9.3