stm32mp: psci: Implement PSCI system suspend and DRAM SSR
authorMarek Vasut <marex@denx.de>
Fri, 25 Feb 2022 01:15:59 +0000 (02:15 +0100)
committerPatrice Chotard <patrice.chotard@foss.st.com>
Tue, 15 Mar 2022 08:16:55 +0000 (09:16 +0100)
Implement PSCI system suspend and placement of DRAM into SSR while the
CPUs are in suspend. This saves non-trivial amount of power in suspend,
on 2x W632GU6NB-15 ~710mW.

Reviewed-by: Patrice Chotard <patrice.chotard@foss.st.com>
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Patrick Delaunay <patrick.delaunay@foss.st.com>
Cc: Patrice Chotard <patrice.chotard@foss.st.com>
arch/arm/mach-stm32mp/include/mach/stm32.h
arch/arm/mach-stm32mp/psci.c

index c11a990..47e88fc 100644 (file)
  */
 #define STM32_RCC_BASE                 0x50000000
 #define STM32_PWR_BASE                 0x50001000
+#define STM32_SYSCFG_BASE              0x50020000
 #define STM32_DBGMCU_BASE              0x50081000
 #define STM32_FMC2_BASE                        0x58002000
+#define STM32_DDRCTRL_BASE             0x5A003000
+#define STM32_DDRPHYC_BASE             0x5A004000
 #define STM32_TZC_BASE                 0x5C006000
 #define STM32_ETZPC_BASE               0x5C007000
 #define STM32_STGEN_BASE               0x5C008000
index 155aa79..86c1609 100644 (file)
 #include <asm/io.h>
 #include <asm/psci.h>
 #include <asm/secure.h>
+#include <hang.h>
 #include <linux/bitops.h>
 
-#define BOOT_API_A7_CORE0_MAGIC_NUMBER 0xCA7FACE0
-#define BOOT_API_A7_CORE1_MAGIC_NUMBER 0xCA7FACE1
-
-#define MPIDR_AFF0                     GENMASK(7, 0)
-
-#define RCC_MP_GRSTCSETR               (STM32_RCC_BASE + 0x0404)
-#define RCC_MP_GRSTCSETR_MPUP1RST      BIT(5)
-#define RCC_MP_GRSTCSETR_MPUP0RST      BIT(4)
-#define RCC_MP_GRSTCSETR_MPSYSRST      BIT(0)
-
-#define STM32MP1_PSCI_NR_CPUS          2
+/* PWR */
+#define PWR_CR3                                        0x0c
+#define PWR_MPUCR                              0x10
+
+#define PWR_CR3_DDRSREN                                BIT(10)
+#define PWR_CR3_DDRRETEN                       BIT(12)
+
+#define PWR_MPUCR_PDDS                         BIT(0)
+#define PWR_MPUCR_CSTDBYDIS                    BIT(3)
+#define PWR_MPUCR_CSSF                         BIT(9)
+
+/* RCC */
+#define RCC_DDRITFCR                           0xd8
+
+#define RCC_DDRITFCR_DDRC1EN                   BIT(0)
+#define RCC_DDRITFCR_DDRC1LPEN                 BIT(1)
+#define RCC_DDRITFCR_DDRC2EN                   BIT(2)
+#define RCC_DDRITFCR_DDRC2LPEN                 BIT(3)
+#define RCC_DDRITFCR_DDRPHYCEN                 BIT(4)
+#define RCC_DDRITFCR_DDRPHYCLPEN               BIT(5)
+#define RCC_DDRITFCR_DDRCAPBEN                 BIT(6)
+#define RCC_DDRITFCR_DDRCAPBLPEN               BIT(7)
+#define RCC_DDRITFCR_AXIDCGEN                  BIT(8)
+#define RCC_DDRITFCR_DDRPHYCAPBEN              BIT(9)
+#define RCC_DDRITFCR_DDRPHYCAPBLPEN            BIT(10)
+#define RCC_DDRITFCR_DDRCKMOD_MASK             GENMASK(22, 20)
+#define RCC_DDRITFCR_GSKPCTRL                  BIT(24)
+
+#define RCC_MP_SREQSETR                                0x104
+#define RCC_MP_SREQCLRR                                0x108
+
+#define RCC_MP_CIER                            0x414
+#define RCC_MP_CIFR                            0x418
+#define RCC_MP_CIFR_WKUPF                      BIT(20)
+
+/* SYSCFG */
+#define SYSCFG_CMPCR                           0x20
+#define SYSCFG_CMPCR_SW_CTRL                   BIT(2)
+#define SYSCFG_CMPENSETR                       0x24
+#define SYSCFG_CMPENCLRR                       0x28
+#define SYSCFG_CMPENR_MPUEN                    BIT(0)
+
+/* DDR Controller registers offsets */
+#define DDRCTRL_STAT                           0x004
+#define DDRCTRL_PWRCTL                         0x030
+#define DDRCTRL_PWRTMG                         0x034
+#define DDRCTRL_HWLPCTL                                0x038
+#define DDRCTRL_DFIMISC                                0x1b0
+#define DDRCTRL_SWCTL                          0x320
+#define DDRCTRL_SWSTAT                         0x324
+#define DDRCTRL_PSTAT                          0x3fc
+#define DDRCTRL_PCTRL_0                                0x490
+#define DDRCTRL_PCTRL_1                                0x540
+
+/* DDR Controller Register fields */
+#define DDRCTRL_STAT_OPERATING_MODE_MASK       GENMASK(2, 0)
+#define DDRCTRL_STAT_OPERATING_MODE_NORMAL     0x1
+#define DDRCTRL_STAT_OPERATING_MODE_SR         0x3
+#define DDRCTRL_STAT_SELFREF_TYPE_MASK         GENMASK(5, 4)
+#define DDRCTRL_STAT_SELFREF_TYPE_ASR          (0x3 << 4)
+#define DDRCTRL_STAT_SELFREF_TYPE_SR           (0x2 << 4)
+
+#define DDRCTRL_PWRCTL_SELFREF_EN              BIT(0)
+#define DDRCTRL_PWRCTL_EN_DFI_DRAM_CLK_DISABLE BIT(3)
+#define DDRCTRL_PWRCTL_SELFREF_SW              BIT(5)
+
+#define DDRCTRL_PWRTMG_SELFREF_TO_X32_MASK     GENMASK(23, 16)
+#define DDRCTRL_PWRTMG_SELFREF_TO_X32_0                BIT(16)
+
+#define DDRCTRL_HWLPCTL_HW_LP_EN               BIT(0)
+
+#define DDRCTRL_DFIMISC_DFI_INIT_COMPLETE_EN   BIT(0)
+
+#define DDRCTRL_SWCTL_SW_DONE                  BIT(0)
+
+#define DDRCTRL_SWSTAT_SW_DONE_ACK             BIT(0)
+
+#define DDRCTRL_PSTAT_RD_PORT_BUSY_0           BIT(0)
+#define DDRCTRL_PSTAT_RD_PORT_BUSY_1           BIT(1)
+#define DDRCTRL_PSTAT_WR_PORT_BUSY_0           BIT(16)
+#define DDRCTRL_PSTAT_WR_PORT_BUSY_1           BIT(17)
+
+#define DDRCTRL_PCTRL_N_PORT_EN                        BIT(0)
+
+/* DDR PHY registers offsets */
+#define DDRPHYC_PIR                            0x004
+#define DDRPHYC_PGSR                           0x00c
+#define DDRPHYC_ACDLLCR                                0x014
+#define DDRPHYC_ACIOCR                         0x024
+#define DDRPHYC_DXCCR                          0x028
+#define DDRPHYC_DSGCR                          0x02c
+#define DDRPHYC_ZQ0CR0                         0x180
+#define DDRPHYC_DX0DLLCR                       0x1cc
+#define DDRPHYC_DX1DLLCR                       0x20c
+#define DDRPHYC_DX2DLLCR                       0x24c
+#define DDRPHYC_DX3DLLCR                       0x28c
+
+/* DDR PHY Register fields */
+#define DDRPHYC_PIR_INIT                       BIT(0)
+#define DDRPHYC_PIR_DLLSRST                    BIT(1)
+#define DDRPHYC_PIR_DLLLOCK                    BIT(2)
+#define DDRPHYC_PIR_ITMSRST                    BIT(4)
+
+#define DDRPHYC_PGSR_IDONE                     BIT(0)
+
+#define DDRPHYC_ACDLLCR_DLLSRST                        BIT(30)
+#define DDRPHYC_ACDLLCR_DLLDIS                 BIT(31)
+
+#define DDRPHYC_ACIOCR_ACOE                    BIT(1)
+#define DDRPHYC_ACIOCR_ACPDD                   BIT(3)
+#define DDRPHYC_ACIOCR_ACPDR                   BIT(4)
+#define DDRPHYC_ACIOCR_CKPDD_MASK              GENMASK(10, 8)
+#define DDRPHYC_ACIOCR_CKPDD_0                 BIT(8)
+#define DDRPHYC_ACIOCR_CKPDR_MASK              GENMASK(13, 11)
+#define DDRPHYC_ACIOCR_CKPDR_0                 BIT(11)
+#define DDRPHYC_ACIOCR_CSPDD_MASK              GENMASK(20, 18)
+#define DDRPHYC_ACIOCR_CSPDD_0                 BIT(18)
+
+#define DDRPHYC_DXCCR_DXPDD                    BIT(2)
+#define DDRPHYC_DXCCR_DXPDR                    BIT(3)
+
+#define DDRPHYC_DSGCR_CKEPDD_MASK              GENMASK(19, 16)
+#define DDRPHYC_DSGCR_CKEPDD_0                 BIT(16)
+#define DDRPHYC_DSGCR_ODTPDD_MASK              GENMASK(23, 20)
+#define DDRPHYC_DSGCR_ODTPDD_0                 BIT(20)
+#define DDRPHYC_DSGCR_NL2PD                    BIT(24)
+#define DDRPHYC_DSGCR_CKOE                     BIT(28)
+
+#define DDRPHYC_ZQ0CRN_ZQPD                    BIT(31)
+
+#define DDRPHYC_DXNDLLCR_DLLDIS                        BIT(31)
+
+#define BOOT_API_A7_CORE0_MAGIC_NUMBER         0xca7face0
+#define BOOT_API_A7_CORE1_MAGIC_NUMBER         0xca7face1
+
+#define MPIDR_AFF0                             GENMASK(7, 0)
+
+#define RCC_MP_GRSTCSETR                       (STM32_RCC_BASE + 0x0404)
+#define RCC_MP_GRSTCSETR_MPSYSRST              BIT(0)
+#define RCC_MP_GRSTCSETR_MPUP0RST              BIT(4)
+#define RCC_MP_GRSTCSETR_MPUP1RST              BIT(5)
+
+#define STM32MP1_PSCI_NR_CPUS                  2
 #if STM32MP1_PSCI_NR_CPUS > CONFIG_ARMV7_PSCI_NR_CPUS
 #error "invalid value for CONFIG_ARMV7_PSCI_NR_CPUS"
 #endif
@@ -98,6 +231,7 @@ s32 __secure psci_features(u32 function_id, u32 psci_fid)
        case ARM_PSCI_0_2_FN_MIGRATE_INFO_TYPE:
        case ARM_PSCI_0_2_FN_SYSTEM_OFF:
        case ARM_PSCI_0_2_FN_SYSTEM_RESET:
+       case ARM_PSCI_1_0_FN_SYSTEM_SUSPEND:
                return 0x0;
        }
        return ARM_PSCI_RET_NI;
@@ -222,3 +356,374 @@ void __secure psci_system_off(void)
        while (1)
                wfi();
 }
+
+static void __secure secure_udelay(unsigned int delay)
+{
+       u32 freq = cp15_read_cntfrq() / 1000000;
+       u64 start, end;
+
+       delay *= freq;
+
+       asm volatile("mrrc p15, 0, %Q0, %R0, c14" : "=r" (start));
+       for (;;) {
+               asm volatile("mrrc p15, 0, %Q0, %R0, c14" : "=r" (end));
+               if ((end - start) > delay)
+                       break;
+       }
+}
+
+static int __secure secure_waitbits(u32 reg, u32 mask, u32 val)
+{
+       u32 freq = cp15_read_cntfrq() / 1000000;
+       u32 delay = 500 * freq; /* 500 us */
+       u64 start, end;
+       u32 tmp;
+
+       asm volatile("mrrc p15, 0, %Q0, %R0, c14" : "=r" (start));
+       for (;;) {
+               tmp = readl(reg);
+               tmp &= mask;
+               if ((tmp & val) == val)
+                       return 0;
+               asm volatile("mrrc p15, 0, %Q0, %R0, c14" : "=r" (end));
+               if ((end - start) > delay)
+                       return -ETIMEDOUT;
+       }
+}
+
+static void __secure ddr_sr_mode_ssr(u32 *saved_pwrctl)
+{
+       setbits_le32(STM32_RCC_BASE + RCC_DDRITFCR,
+                    RCC_DDRITFCR_DDRC1LPEN | RCC_DDRITFCR_DDRC1EN |
+                    RCC_DDRITFCR_DDRC2LPEN | RCC_DDRITFCR_DDRC2EN |
+                    RCC_DDRITFCR_DDRCAPBLPEN | RCC_DDRITFCR_DDRPHYCAPBLPEN |
+                    RCC_DDRITFCR_DDRCAPBEN | RCC_DDRITFCR_DDRPHYCAPBEN |
+                    RCC_DDRITFCR_DDRPHYCEN);
+
+       clrbits_le32(STM32_RCC_BASE + RCC_DDRITFCR,
+                    RCC_DDRITFCR_AXIDCGEN | RCC_DDRITFCR_DDRCKMOD_MASK);
+
+       /* Disable HW LP interface of uMCTL2 */
+       clrbits_le32(STM32_DDRCTRL_BASE + DDRCTRL_HWLPCTL,
+                    DDRCTRL_HWLPCTL_HW_LP_EN);
+
+       /* Configure Automatic LP modes of uMCTL2 */
+       clrsetbits_le32(STM32_DDRCTRL_BASE + DDRCTRL_PWRTMG,
+                       DDRCTRL_PWRTMG_SELFREF_TO_X32_MASK,
+                       DDRCTRL_PWRTMG_SELFREF_TO_X32_0);
+
+       /* Save PWRCTL register to restart ASR after suspend (if applicable) */
+       *saved_pwrctl = readl(STM32_DDRCTRL_BASE + DDRCTRL_PWRCTL);
+
+       /*
+        * Disable Clock disable with LP modes
+        * (used in RUN mode for LPDDR2 with specific timing).
+        */
+       clrbits_le32(STM32_DDRCTRL_BASE + DDRCTRL_PWRCTL,
+                    DDRCTRL_PWRCTL_EN_DFI_DRAM_CLK_DISABLE);
+
+       /* Disable automatic Self-Refresh mode */
+       clrbits_le32(STM32_DDRCTRL_BASE + DDRCTRL_PWRCTL,
+                    DDRCTRL_PWRCTL_SELFREF_EN);
+}
+
+static void __secure ddr_sr_mode_restore(u32 saved_pwrctl)
+{
+       saved_pwrctl &= DDRCTRL_PWRCTL_EN_DFI_DRAM_CLK_DISABLE |
+                       DDRCTRL_PWRCTL_SELFREF_EN;
+
+       /* Restore ASR mode in case it was enabled before suspend. */
+       setbits_le32(STM32_DDRCTRL_BASE + DDRCTRL_PWRCTL, saved_pwrctl);
+}
+
+static int __secure ddr_sw_self_refresh_in(void)
+{
+       int ret;
+
+       clrbits_le32(STM32_RCC_BASE + RCC_DDRITFCR, RCC_DDRITFCR_AXIDCGEN);
+
+       /* Blocks AXI ports from taking anymore transactions */
+       clrbits_le32(STM32_DDRCTRL_BASE + DDRCTRL_PCTRL_0,
+                    DDRCTRL_PCTRL_N_PORT_EN);
+       clrbits_le32(STM32_DDRCTRL_BASE + DDRCTRL_PCTRL_1,
+                    DDRCTRL_PCTRL_N_PORT_EN);
+
+       /*
+        * Waits unit all AXI ports are idle
+        * Poll PSTAT.rd_port_busy_n = 0
+        * Poll PSTAT.wr_port_busy_n = 0
+        */
+       ret = secure_waitbits(STM32_DDRCTRL_BASE + DDRCTRL_PSTAT,
+                             DDRCTRL_PSTAT_RD_PORT_BUSY_0 |
+                             DDRCTRL_PSTAT_RD_PORT_BUSY_1 |
+                             DDRCTRL_PSTAT_WR_PORT_BUSY_0 |
+                             DDRCTRL_PSTAT_WR_PORT_BUSY_1, 0);
+       if (ret)
+               goto pstat_failed;
+
+       /* SW Self-Refresh entry */
+       setbits_le32(STM32_DDRCTRL_BASE + DDRCTRL_PWRCTL, DDRCTRL_PWRCTL_SELFREF_SW);
+
+       /*
+        * Wait operating mode change in self-refresh mode
+        * with STAT.operating_mode[1:0]==11.
+        * Ensure transition to self-refresh was due to software
+        * by checking also that STAT.selfref_type[1:0]=2.
+        */
+       ret = secure_waitbits(STM32_DDRCTRL_BASE + DDRCTRL_STAT,
+                             DDRCTRL_STAT_OPERATING_MODE_MASK |
+                             DDRCTRL_STAT_SELFREF_TYPE_MASK,
+                             DDRCTRL_STAT_OPERATING_MODE_SR |
+                             DDRCTRL_STAT_SELFREF_TYPE_SR);
+       if (ret)
+               goto selfref_sw_failed;
+
+       /* IOs powering down (PUBL registers) */
+       setbits_le32(STM32_DDRPHYC_BASE + DDRPHYC_ACIOCR, DDRPHYC_ACIOCR_ACPDD);
+       setbits_le32(STM32_DDRPHYC_BASE + DDRPHYC_ACIOCR, DDRPHYC_ACIOCR_ACPDR);
+
+       clrsetbits_le32(STM32_DDRPHYC_BASE + DDRPHYC_ACIOCR,
+                       DDRPHYC_ACIOCR_CKPDD_MASK,
+                       DDRPHYC_ACIOCR_CKPDD_0);
+
+       clrsetbits_le32(STM32_DDRPHYC_BASE + DDRPHYC_ACIOCR,
+                       DDRPHYC_ACIOCR_CKPDR_MASK,
+                       DDRPHYC_ACIOCR_CKPDR_0);
+
+       clrsetbits_le32(STM32_DDRPHYC_BASE + DDRPHYC_ACIOCR,
+                       DDRPHYC_ACIOCR_CSPDD_MASK,
+                       DDRPHYC_ACIOCR_CSPDD_0);
+
+       /* Disable command/address output driver */
+       clrbits_le32(STM32_DDRPHYC_BASE + DDRPHYC_ACIOCR, DDRPHYC_ACIOCR_ACOE);
+
+       setbits_le32(STM32_DDRPHYC_BASE + DDRPHYC_DXCCR, DDRPHYC_DXCCR_DXPDD);
+
+       setbits_le32(STM32_DDRPHYC_BASE + DDRPHYC_DXCCR, DDRPHYC_DXCCR_DXPDR);
+
+       clrsetbits_le32(STM32_DDRPHYC_BASE + DDRPHYC_DSGCR,
+                       DDRPHYC_DSGCR_ODTPDD_MASK,
+                       DDRPHYC_DSGCR_ODTPDD_0);
+
+       setbits_le32(STM32_DDRPHYC_BASE + DDRPHYC_DSGCR, DDRPHYC_DSGCR_NL2PD);
+
+       clrsetbits_le32(STM32_DDRPHYC_BASE + DDRPHYC_DSGCR,
+                       DDRPHYC_DSGCR_CKEPDD_MASK,
+                       DDRPHYC_DSGCR_CKEPDD_0);
+
+       /* Disable PZQ cell (PUBL register) */
+       setbits_le32(STM32_DDRPHYC_BASE + DDRPHYC_ZQ0CR0, DDRPHYC_ZQ0CRN_ZQPD);
+
+       /* Set latch */
+       clrbits_le32(STM32_DDRPHYC_BASE + DDRPHYC_DSGCR, DDRPHYC_DSGCR_CKOE);
+
+       /* Additional delay to avoid early latch */
+       secure_udelay(10);
+
+       /* Activate sw retention in PWRCTRL */
+       setbits_le32(STM32_PWR_BASE + PWR_CR3, PWR_CR3_DDRRETEN);
+
+       /* Switch controller clocks (uMCTL2/PUBL) to DLL ref clock */
+       setbits_le32(STM32_RCC_BASE + RCC_DDRITFCR, RCC_DDRITFCR_GSKPCTRL);
+
+       /* Disable all DLLs: GLITCH window */
+       setbits_le32(STM32_DDRPHYC_BASE + DDRPHYC_ACDLLCR, DDRPHYC_ACDLLCR_DLLDIS);
+
+       setbits_le32(STM32_DDRPHYC_BASE + DDRPHYC_DX0DLLCR, DDRPHYC_DXNDLLCR_DLLDIS);
+
+       setbits_le32(STM32_DDRPHYC_BASE + DDRPHYC_DX1DLLCR, DDRPHYC_DXNDLLCR_DLLDIS);
+
+       setbits_le32(STM32_DDRPHYC_BASE + DDRPHYC_DX2DLLCR, DDRPHYC_DXNDLLCR_DLLDIS);
+
+       setbits_le32(STM32_DDRPHYC_BASE + DDRPHYC_DX3DLLCR, DDRPHYC_DXNDLLCR_DLLDIS);
+
+       /* Switch controller clocks (uMCTL2/PUBL) to DLL output clock */
+       clrbits_le32(STM32_RCC_BASE + RCC_DDRITFCR, RCC_DDRITFCR_GSKPCTRL);
+
+       /* Deactivate all DDR clocks */
+       clrbits_le32(STM32_RCC_BASE + RCC_DDRITFCR,
+                    RCC_DDRITFCR_DDRC1EN | RCC_DDRITFCR_DDRC2EN |
+                    RCC_DDRITFCR_DDRCAPBEN | RCC_DDRITFCR_DDRPHYCAPBEN);
+
+       return 0;
+
+selfref_sw_failed:
+       /* This bit should be cleared to restore DDR in its previous state */
+       clrbits_le32(STM32_DDRCTRL_BASE + DDRCTRL_PWRCTL,
+                    DDRCTRL_PWRCTL_SELFREF_SW);
+
+pstat_failed:
+       setbits_le32(STM32_DDRCTRL_BASE + DDRCTRL_PCTRL_0,
+                    DDRCTRL_PCTRL_N_PORT_EN);
+       setbits_le32(STM32_DDRCTRL_BASE + DDRCTRL_PCTRL_1,
+                    DDRCTRL_PCTRL_N_PORT_EN);
+
+       return -EINVAL;
+};
+
+static void __secure ddr_sw_self_refresh_exit(void)
+{
+       int ret;
+
+       /* Enable all clocks */
+       setbits_le32(STM32_RCC_BASE + RCC_DDRITFCR,
+                    RCC_DDRITFCR_DDRC1EN | RCC_DDRITFCR_DDRC2EN |
+                    RCC_DDRITFCR_DDRPHYCEN | RCC_DDRITFCR_DDRPHYCAPBEN |
+                    RCC_DDRITFCR_DDRCAPBEN);
+
+       /* Handshake */
+       clrbits_le32(STM32_DDRCTRL_BASE + DDRCTRL_SWCTL, DDRCTRL_SWCTL_SW_DONE);
+
+       /* Mask dfi_init_complete_en */
+       clrbits_le32(STM32_DDRCTRL_BASE + DDRCTRL_DFIMISC,
+                    DDRCTRL_DFIMISC_DFI_INIT_COMPLETE_EN);
+
+       /* Ack */
+       setbits_le32(STM32_DDRCTRL_BASE + DDRCTRL_SWCTL, DDRCTRL_SWCTL_SW_DONE);
+       ret = secure_waitbits(STM32_DDRCTRL_BASE + DDRCTRL_SWSTAT,
+                             DDRCTRL_SWSTAT_SW_DONE_ACK,
+                             DDRCTRL_SWSTAT_SW_DONE_ACK);
+       if (ret)
+               hang();
+
+       /* Switch controller clocks (uMCTL2/PUBL) to DLL ref clock */
+       setbits_le32(STM32_RCC_BASE + RCC_DDRITFCR, RCC_DDRITFCR_GSKPCTRL);
+
+       /* Enable all DLLs: GLITCH window */
+       clrbits_le32(STM32_DDRPHYC_BASE + DDRPHYC_ACDLLCR,
+                    DDRPHYC_ACDLLCR_DLLDIS);
+
+       clrbits_le32(STM32_DDRPHYC_BASE + DDRPHYC_DX0DLLCR, DDRPHYC_DXNDLLCR_DLLDIS);
+
+       clrbits_le32(STM32_DDRPHYC_BASE + DDRPHYC_DX1DLLCR, DDRPHYC_DXNDLLCR_DLLDIS);
+
+       clrbits_le32(STM32_DDRPHYC_BASE + DDRPHYC_DX2DLLCR, DDRPHYC_DXNDLLCR_DLLDIS);
+
+       clrbits_le32(STM32_DDRPHYC_BASE + DDRPHYC_DX3DLLCR, DDRPHYC_DXNDLLCR_DLLDIS);
+
+       /* Additional delay to avoid early DLL clock switch */
+       secure_udelay(50);
+
+       /* Switch controller clocks (uMCTL2/PUBL) to DLL ref clock */
+       clrbits_le32(STM32_RCC_BASE + RCC_DDRITFCR, RCC_DDRITFCR_GSKPCTRL);
+
+       clrbits_le32(STM32_DDRPHYC_BASE + DDRPHYC_ACDLLCR, DDRPHYC_ACDLLCR_DLLSRST);
+
+       secure_udelay(10);
+
+       setbits_le32(STM32_DDRPHYC_BASE + DDRPHYC_ACDLLCR, DDRPHYC_ACDLLCR_DLLSRST);
+
+       /* PHY partial init: (DLL lock and ITM reset) */
+       writel(DDRPHYC_PIR_DLLSRST | DDRPHYC_PIR_DLLLOCK |
+              DDRPHYC_PIR_ITMSRST | DDRPHYC_PIR_INIT,
+              STM32_DDRPHYC_BASE + DDRPHYC_PIR);
+
+       /* Need to wait at least 10 clock cycles before accessing PGSR */
+       secure_udelay(1);
+
+       /* Pool end of init */
+       ret = secure_waitbits(STM32_DDRPHYC_BASE + DDRPHYC_PGSR,
+                             DDRPHYC_PGSR_IDONE, DDRPHYC_PGSR_IDONE);
+       if (ret)
+               hang();
+
+       /* Handshake */
+       clrbits_le32(STM32_DDRCTRL_BASE + DDRCTRL_SWCTL, DDRCTRL_SWCTL_SW_DONE);
+
+       /* Unmask dfi_init_complete_en to uMCTL2 */
+       setbits_le32(STM32_DDRCTRL_BASE + DDRCTRL_DFIMISC, DDRCTRL_DFIMISC_DFI_INIT_COMPLETE_EN);
+
+       /* Ack */
+       setbits_le32(STM32_DDRCTRL_BASE + DDRCTRL_SWCTL, DDRCTRL_SWCTL_SW_DONE);
+       ret = secure_waitbits(STM32_DDRCTRL_BASE + DDRCTRL_SWSTAT,
+                             DDRCTRL_SWSTAT_SW_DONE_ACK,
+                             DDRCTRL_SWSTAT_SW_DONE_ACK);
+       if (ret)
+               hang();
+
+       /* Deactivate sw retention in PWR */
+       clrbits_le32(STM32_PWR_BASE + PWR_CR3, PWR_CR3_DDRRETEN);
+
+       /* Enable PZQ cell (PUBL register) */
+       clrbits_le32(STM32_DDRPHYC_BASE + DDRPHYC_ZQ0CR0, DDRPHYC_ZQ0CRN_ZQPD);
+
+       /* Enable pad drivers */
+       clrbits_le32(STM32_DDRPHYC_BASE + DDRPHYC_ACIOCR, DDRPHYC_ACIOCR_ACPDD);
+
+       /* Enable command/address output driver */
+       setbits_le32(STM32_DDRPHYC_BASE + DDRPHYC_ACIOCR, DDRPHYC_ACIOCR_ACOE);
+
+       clrbits_le32(STM32_DDRPHYC_BASE + DDRPHYC_ACIOCR, DDRPHYC_ACIOCR_CKPDD_MASK);
+
+       clrbits_le32(STM32_DDRPHYC_BASE + DDRPHYC_ACIOCR, DDRPHYC_ACIOCR_CSPDD_MASK);
+
+       clrbits_le32(STM32_DDRPHYC_BASE + DDRPHYC_DXCCR, DDRPHYC_DXCCR_DXPDD);
+
+       clrbits_le32(STM32_DDRPHYC_BASE + DDRPHYC_DXCCR, DDRPHYC_DXCCR_DXPDR);
+
+       /* Release latch */
+       setbits_le32(STM32_DDRPHYC_BASE + DDRPHYC_DSGCR, DDRPHYC_DSGCR_CKOE);
+
+       clrbits_le32(STM32_DDRPHYC_BASE + DDRPHYC_DSGCR, DDRPHYC_DSGCR_ODTPDD_MASK);
+
+       clrbits_le32(STM32_DDRPHYC_BASE + DDRPHYC_DSGCR, DDRPHYC_DSGCR_NL2PD);
+
+       clrbits_le32(STM32_DDRPHYC_BASE + DDRPHYC_DSGCR, DDRPHYC_DSGCR_CKEPDD_MASK);
+
+       /* Remove selfrefresh */
+       clrbits_le32(STM32_DDRCTRL_BASE + DDRCTRL_PWRCTL, DDRCTRL_PWRCTL_SELFREF_SW);
+
+       /* Wait operating_mode == normal */
+       ret = secure_waitbits(STM32_DDRCTRL_BASE + DDRCTRL_STAT,
+                             DDRCTRL_STAT_OPERATING_MODE_MASK,
+                             DDRCTRL_STAT_OPERATING_MODE_NORMAL);
+       if (ret)
+               hang();
+
+       /* AXI ports are no longer blocked from taking transactions */
+       setbits_le32(STM32_DDRCTRL_BASE + DDRCTRL_PCTRL_0, DDRCTRL_PCTRL_N_PORT_EN);
+       setbits_le32(STM32_DDRCTRL_BASE + DDRCTRL_PCTRL_1, DDRCTRL_PCTRL_N_PORT_EN);
+
+       setbits_le32(STM32_RCC_BASE + RCC_DDRITFCR, RCC_DDRITFCR_AXIDCGEN);
+}
+
+void __secure psci_system_suspend(u32 __always_unused function_id,
+                                 u32 ep, u32 context_id)
+{
+       u32 saved_pwrctl, reg;
+
+       /* Disable IO compensation */
+
+       /* Place current APSRC/ANSRC into RAPSRC/RANSRC */
+       reg = readl(STM32_SYSCFG_BASE + SYSCFG_CMPCR);
+       reg >>= 8;
+       reg &= 0xff << 16;
+       reg |= SYSCFG_CMPCR_SW_CTRL;
+       writel(reg, STM32_SYSCFG_BASE + SYSCFG_CMPCR);
+       writel(SYSCFG_CMPENR_MPUEN, STM32_SYSCFG_BASE + SYSCFG_CMPENCLRR);
+
+       writel(RCC_MP_CIFR_WKUPF, STM32_RCC_BASE + RCC_MP_CIFR);
+       setbits_le32(STM32_RCC_BASE + RCC_MP_CIER, RCC_MP_CIFR_WKUPF);
+
+       setbits_le32(STM32_PWR_BASE + PWR_MPUCR,
+                    PWR_MPUCR_CSSF | PWR_MPUCR_CSTDBYDIS | PWR_MPUCR_PDDS);
+
+       psci_v7_flush_dcache_all();
+       ddr_sr_mode_ssr(&saved_pwrctl);
+       ddr_sw_self_refresh_in();
+       setbits_le32(STM32_PWR_BASE + PWR_CR3, PWR_CR3_DDRSREN);
+       writel(0x3, STM32_RCC_BASE + RCC_MP_SREQSETR);
+
+       /* Zzz, enter stop mode */
+       asm volatile(
+               "isb\n"
+               "dsb\n"
+               "wfi\n");
+
+       writel(0x3, STM32_RCC_BASE + RCC_MP_SREQCLRR);
+       ddr_sw_self_refresh_exit();
+       ddr_sr_mode_restore(saved_pwrctl);
+
+       writel(SYSCFG_CMPENR_MPUEN, STM32_SYSCFG_BASE + SYSCFG_CMPENSETR);
+       clrbits_le32(STM32_SYSCFG_BASE + SYSCFG_CMPCR, SYSCFG_CMPCR_SW_CTRL);
+}