[U-Boot] [PATCH 3/3] ARM: rmobile: Add possibility to debug main PSCI commands
Oleksandr
olekstysh at gmail.com
Fri Feb 8 12:47:14 UTC 2019
On 05.02.19 20:56, Marek Vasut wrote:
Hi Marek
> On 1/31/19 6:38 PM, Oleksandr Tyshchenko wrote:
>> From: Oleksandr Tyshchenko <oleksandr_tyshchenko at epam.com>
>>
>> Also take care of the fact that Lager and Stout boards use
>> different serial interface for console.
> This describes something else than $subject , please split the patchset
> such that one patch does one thing and describes that one thing in the
> commit message.
Yes, make sense. Will split.
>> Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko at epam.com>
>> ---
>> arch/arm/mach-rmobile/debug.h | 91 +++++++++++++++++++++++++++++++++++++++++++
>> arch/arm/mach-rmobile/psci.c | 23 +++++++++++
>> 2 files changed, 114 insertions(+)
>> create mode 100644 arch/arm/mach-rmobile/debug.h
>>
>> diff --git a/arch/arm/mach-rmobile/debug.h b/arch/arm/mach-rmobile/debug.h
>> new file mode 100644
>> index 0000000..5d4ec77
>> --- /dev/null
>> +++ b/arch/arm/mach-rmobile/debug.h
>> @@ -0,0 +1,91 @@
>> +/* SPDX-License-Identifier: GPL-2.0 */
>> +/*
>> + * Contains functions used for PSCI debug.
>> + *
>> + * Copyright (C) 2018 EPAM Systems Inc.
>> + *
>> + * Based on arch/arm/mach-uniphier/debug.h
>> + */
>> +
>> +#ifndef __DEBUG_H__
>> +#define __DEBUG_H__
>> +
>> +#include <asm/io.h>
>> +
>> +/* SCIFA definitions */
>> +#define SCIFA_BASE 0xe6c40000
> Should come from DT
I have just found that rcar-base.h already contains #define-s for all
SCIF(A)s.
>
>> +#define SCIFA_SCASSR 0x14 /* Serial status register */
>> +#define SCIFA_SCAFTDR 0x20 /* Transmit FIFO data register */
>> +
>> +/* SCIF definitions */
>> +#define SCIF_BASE 0xe6e60000
>> +
>> +#define SCIF_SCFSR 0x10 /* Serial status register */
>> +#define SCIF_SCFTDR 0x0c /* Transmit FIFO data register */
>> +
>> +/* Common for both interfaces definitions */
>> +#define SCFSR_TDFE BIT(5) /* Transmit FIFO Data Empty */
>> +#define SCFSR_TEND BIT(6) /* Transmission End */
>> +
>> +#ifdef CONFIG_SCIF_A
>> +#define UART_BASE SCIFA_BASE
>> +#define UART_STATUS_REG SCIFA_SCASSR
>> +#define UART_TX_FIFO_REG SCIFA_SCAFTDR
>> +#else
>> +#define UART_BASE SCIF_BASE
>> +#define UART_STATUS_REG SCIF_SCFSR
>> +#define UART_TX_FIFO_REG SCIF_SCFTDR
>> +#endif
>> +
>> +/* All functions are inline so that they can be called from .secure section. */
>> +
>> +#ifdef DEBUG
>> +static inline void debug_putc(int c)
>> +{
>> + void __iomem *base = (void __iomem *)UART_BASE;
>> +
>> + while (!(readw(base + UART_STATUS_REG) & SCFSR_TDFE))
>> + ;
>> +
>> + writeb(c, base + UART_TX_FIFO_REG);
>> + writew(readw(base + UART_STATUS_REG) & ~(SCFSR_TEND | SCFSR_TDFE),
>> + base + UART_STATUS_REG);
> Is this some implementation of debug uart API or is this a
> reimplementation of the serial driver ?
I would say it is some implementation of debug uart API.
Let me explain why it is needed. We need something very simple to be
called from the PSCI backend
in order to have possibility for debugging it. Actually the only thing
we need is a simple function to write a char into uart TX register.
Actually I borrowed that idea from the implementation for mach-uniphier
and modified according to the SCIF(A) usage.
These are examples, how it looks like:
1.
[ 3.193974] psci_checker: Trying to turn off and on again group 1
(CPUs 4-7)
[U-Boot PSCI] cpu_off: cpu=00000004
[ 3.233648] Retrying again to check for CPU kill
[ 3.238269] CPU4 killed.
[U-Boot PSCI] cpu_off: cpu=00000005
[ 3.263678] Retrying again to check for CPU kill
[ 3.268298] CPU5 killed.
[U-Boot PSCI] cpu_off: cpu=00000006
[ 3.293648] Retrying again to check for CPU kill
[ 3.298268] CPU6 killed.
[U-Boot PSCI] cpu_off: cpu=00000007
[ 3.323691] Retrying again to check for CPU kill
[ 3.328310] CPU7 killed.
[U-Boot PSCI] cpu_on: cpu=00000001, target_cpu=00000100,
entry_point=48102440, context_id=00000000
[U-Boot PSCI] cpu_on: cpu=00000002, target_cpu=00000101,
entry_point=48102440, context_id=00000000
[U-Boot PSCI] cpu_on: cpu=00000001, target_cpu=00000102,
entry_point=48102440, context_id=00000000
[U-Boot PSCI] cpu_on: cpu=00000001, target_cpu=00000103,
entry_point=48102440, context_id=00000000
2.
(XEN) Bringing up CPU4
[U-Boot PSCI] cpu_on: cpu=00000000, target_cpu=00000100,
entry_point=4800004c, context_id=0030e208
- CPU 00000100 booting -
- Xen starting in Hyp mode -
- Setting up control registers -
- Turning on paging -
- Ready -
(XEN) Adding cpu 4 to runqueue 0
(XEN) CPU 4 booted.
(XEN) Bringing up CPU5
[U-Boot PSCI] cpu_on: cpu=00000000, target_cpu=00000101,
entry_point=4800004c, context_id=0030e208
- CPU 00000101 booting -
- Xen starting in Hyp mode -
- Setting up control registers -
- Turning on paging -
- Ready -
(XEN) Adding cpu 5 to runqueue 0
(XEN) CPU 5 booted.
(XEN) Bringing up CPU6
[U-Boot PSCI] cpu_on: cpu=00000000, target_cpu=00000102,
entry_point=4800004c, context_id=0030e208
- CPU 00000102 booting -
- Xen starting in Hyp mode -
- Setting up control registers -
- Turning on paging -
- Ready -
(XEN) Adding cpu 6 to runqueue 0
(XEN) CPU 6 booted.
(XEN) Bringing up CPU7
[U-Boot PSCI] cpu_on: cpu=00000000, target_cpu=00000103,
entry_point=4800004c, context_id=0030e208
- CPU 00000103 booting -
- Xen starting in Hyp mode -
- Setting up control registers -
- Turning on paging -
- Ready -
(XEN) Adding cpu 7 to runqueue 0
(XEN) Brought up 8 CPUs
(XEN) CPU 7 booted.
>> +}
>> +
>> +static inline void debug_puts(const char *s)
>> +{
>> + while (*s) {
>> + if (*s == '\n')
>> + debug_putc('\r');
>> +
>> + debug_putc(*s++);
>> + }
>> +}
>> +
>> +static inline void debug_puth(unsigned long val)
>> +{
>> + int i;
>> + unsigned char c;
>> +
>> + for (i = 8; i--; ) {
>> + c = ((val >> (i * 4)) & 0xf);
>> + c += (c >= 10) ? 'a' - 10 : '0';
>> + debug_putc(c);
>> + }
>> +}
>> +#else
>> +static inline void debug_putc(int c)
>> +{
>> +}
>> +
>> +static inline void debug_puts(const char *s)
>> +{
>> +}
>> +
>> +static inline void debug_puth(unsigned long val)
>> +{
>> +}
>> +#endif
>> +
>> +#endif /* __DEBUG_H__ */
>> diff --git a/arch/arm/mach-rmobile/psci.c b/arch/arm/mach-rmobile/psci.c
>> index 95850b8..4d78b0f 100644
>> --- a/arch/arm/mach-rmobile/psci.c
>> +++ b/arch/arm/mach-rmobile/psci.c
>> @@ -14,6 +14,7 @@
>> #include <asm/secure.h>
>>
>> #include "pm-r8a7790.h"
>> +#include "debug.h"
>>
>> #define R8A7790_PSCI_NR_CPUS 8
>> #if R8A7790_PSCI_NR_CPUS > CONFIG_ARMV7_PSCI_NR_CPUS
>> @@ -105,6 +106,16 @@ int __secure psci_cpu_on(u32 function_id, u32 target_cpu, u32 entry_point,
>> {
>> int cpu;
>>
>> + debug_puts("[U-Boot PSCI] cpu_on: cpu=");
>> + debug_puth(get_current_cpu());
>> + debug_puts(", target_cpu=");
>> + debug_puth(target_cpu);
>> + debug_puts(", entry_point=");
>> + debug_puth(entry_point);
>> + debug_puts(", context_id=");
>> + debug_puth(context_id);
>> + debug_puts("\n");
>> +
>> cpu = mpidr_to_cpu_index(target_cpu);
>> if (cpu == -1)
>> return ARM_PSCI_RET_INVAL;
>> @@ -130,6 +141,10 @@ int __secure psci_cpu_off(void)
>> {
>> int cpu = get_current_cpu();
>>
>> + debug_puts("[U-Boot PSCI] cpu_off: cpu=");
>> + debug_puth(cpu);
>> + debug_puts("\n");
>> +
>> /*
>> * Place the CPU interface in a state where it can never make a CPU
>> * exit WFI as result of an asserted interrupt.
>> @@ -154,6 +169,10 @@ int __secure psci_cpu_off(void)
>>
>> void __secure psci_system_reset(u32 function_id)
>> {
>> + debug_puts("[U-Boot PSCI] system_reset: cpu=");
>> + debug_puth(get_current_cpu());
>> + debug_puts("\n");
>> +
>> r8a7790_system_reset();
>>
>> /* Drain the WB before WFI */
>> @@ -166,6 +185,10 @@ void __secure psci_system_reset(u32 function_id)
>>
>> void __secure psci_system_off(u32 function_id)
>> {
>> + debug_puts("[U-Boot PSCI] system_off: cpu=");
>> + debug_puth(get_current_cpu());
>> + debug_puts("\n");
>> +
>> /* Drain the WB before WFI */
>> dsb();
>>
>>
>
--
Regards,
Oleksandr Tyshchenko
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