As debugger must be totally closed on Sec closed chip, the DBGMCU_IDC register is no more accessible (self hosted debug is disabled with OTP).
This patch adds a function bsec_dbgswenable() to check if the DBGMCU registers are available before to access them: BSEC_DENABLE.DBGSWENABLE = self hosted debug status.
Signed-off-by: Patrick Delaunay patrick.delaunay@st.com ---
arch/arm/mach-stm32mp/bsec.c | 25 +++++++++++++++++++++++ arch/arm/mach-stm32mp/cpu.c | 22 ++++++++++++++++---- arch/arm/mach-stm32mp/include/mach/bsec.h | 7 +++++++ 3 files changed, 50 insertions(+), 4 deletions(-) create mode 100644 arch/arm/mach-stm32mp/include/mach/bsec.h
diff --git a/arch/arm/mach-stm32mp/bsec.c b/arch/arm/mach-stm32mp/bsec.c index fc39230113..c4b33ff241 100644 --- a/arch/arm/mach-stm32mp/bsec.c +++ b/arch/arm/mach-stm32mp/bsec.c @@ -8,6 +8,7 @@ #include <log.h> #include <misc.h> #include <asm/io.h> +#include <asm/arch/bsec.h> #include <asm/arch/stm32mp1_smc.h> #include <linux/arm-smccc.h> #include <linux/iopoll.h> @@ -21,6 +22,7 @@ #define BSEC_OTP_WRDATA_OFF 0x008 #define BSEC_OTP_STATUS_OFF 0x00C #define BSEC_OTP_LOCK_OFF 0x010 +#define BSEC_DENABLE_OFF 0x014 #define BSEC_DISTURBED_OFF 0x01C #define BSEC_ERROR_OFF 0x034 #define BSEC_WRLOCK_OFF 0x04C /* OTP write permananet lock */ @@ -46,6 +48,9 @@ #define BSEC_MODE_PROGFAIL_MASK 0x10 #define BSEC_MODE_PWR_MASK 0x20
+/* DENABLE Register */ +#define BSEC_DENABLE_DBGSWENABLE BIT(10) + /* * OTP Lock services definition * Value must corresponding to the bit number in the register @@ -505,3 +510,23 @@ U_BOOT_DRIVER(stm32mp_bsec) = { .probe = stm32mp_bsec_probe, #endif }; + +bool bsec_dbgswenable(void) +{ + struct udevice *dev; + struct stm32mp_bsec_platdata *plat; + int ret; + + ret = uclass_get_device_by_driver(UCLASS_MISC, + DM_GET_DRIVER(stm32mp_bsec), &dev); + if (ret || !dev) { + pr_debug("bsec driver not available\n"); + return false; + } + + plat = dev_get_platdata(dev); + if (readl(plat->base + BSEC_DENABLE_OFF) & BSEC_DENABLE_DBGSWENABLE) + return true; + + return false; +} diff --git a/arch/arm/mach-stm32mp/cpu.c b/arch/arm/mach-stm32mp/cpu.c index 472b140321..382067190c 100644 --- a/arch/arm/mach-stm32mp/cpu.c +++ b/arch/arm/mach-stm32mp/cpu.c @@ -12,6 +12,7 @@ #include <misc.h> #include <net.h> #include <asm/io.h> +#include <asm/arch/bsec.h> #include <asm/arch/stm32.h> #include <asm/arch/sys_proto.h> #include <dm/device.h> @@ -155,8 +156,13 @@ static void dbgmcu_init(void) { setbits_le32(RCC_DBGCFGR, RCC_DBGCFGR_DBGCKEN);
- /* Freeze IWDG2 if Cortex-A7 is in debug mode */ - setbits_le32(DBGMCU_APB4FZ1, DBGMCU_APB4FZ1_IWDG2); + /* + * Freeze IWDG2 if Cortex-A7 is in debug mode + * done in TF-A for TRUSTED boot and + * DBGMCU access is controlled by BSEC_DENABLE.DBGSWENABLE + */ + if (!IS_ENABLED(CONFIG_TFABOOT) && bsec_dbgswenable()) + setbits_le32(DBGMCU_APB4FZ1, DBGMCU_APB4FZ1_IWDG2); } #endif /* !defined(CONFIG_SPL) || defined(CONFIG_SPL_BUILD) */
@@ -276,9 +282,17 @@ void enable_caches(void)
static u32 read_idc(void) { - setbits_le32(RCC_DBGCFGR, RCC_DBGCFGR_DBGCKEN); + /* DBGMCU access is controlled by BSEC_DENABLE.DBGSWENABLE */ + if (bsec_dbgswenable()) { + setbits_le32(RCC_DBGCFGR, RCC_DBGCFGR_DBGCKEN);
- return readl(DBGMCU_IDC); + return readl(DBGMCU_IDC); + } + + if (CONFIG_IS_ENABLED(STM32MP15x)) + return CPU_DEV_STM32MP15; /* STM32MP15x and unknown revision */ + else + return 0x0; }
u32 get_cpu_dev(void) diff --git a/arch/arm/mach-stm32mp/include/mach/bsec.h b/arch/arm/mach-stm32mp/include/mach/bsec.h new file mode 100644 index 0000000000..252eac3946 --- /dev/null +++ b/arch/arm/mach-stm32mp/include/mach/bsec.h @@ -0,0 +1,7 @@ +/* SPDX-License-Identifier: GPL-2.0+ OR BSD-3-Clause */ +/* + * Copyright (C) 2020, STMicroelectronics - All Rights Reserved + */ + +/* check self hosted debug status = BSEC_DENABLE.DBGSWENABLE */ +bool bsec_dbgswenable(void);