From cffb3e76818fee4763a2ce5f2b1eca2d7885e2cf Mon Sep 17 00:00:00 2001 From: Vijay Kumar Date: Wed, 1 Feb 2017 11:34:37 -0800 Subject: sparc64: Set cpu state to offline when stopped CPU needs to be marked offline before stopping it. When not marked offline, the xcall receives HV_EWOULDBLOCK and so assumes that not all CPUs received the message, and retries. After 10000 retries, it finally fails with fatal mondo timeout. Signed-off-by: Vijay Kumar Signed-off-by: David S. Miller --- arch/sparc/kernel/smp_64.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/sparc/kernel/smp_64.c b/arch/sparc/kernel/smp_64.c index 0ce347f8e4cc..712bf1b7f630 100644 --- a/arch/sparc/kernel/smp_64.c +++ b/arch/sparc/kernel/smp_64.c @@ -1443,6 +1443,7 @@ void __irq_entry smp_receive_signal_client(int irq, struct pt_regs *regs) static void stop_this_cpu(void *dummy) { + set_cpu_online(smp_processor_id(), false); prom_stopself(); } @@ -1454,6 +1455,8 @@ void smp_send_stop(void) for_each_online_cpu(cpu) { if (cpu == smp_processor_id()) continue; + + set_cpu_online(cpu, false); #ifdef CONFIG_SUN_LDOMS if (ldom_domaining_enabled) { unsigned long hv_err; -- cgit v1.2.3-70-g09d2 From 7dd4fcf5b70694dc961eb6b954673e4fc9730dbd Mon Sep 17 00:00:00 2001 From: Vijay Kumar Date: Wed, 1 Feb 2017 11:34:38 -0800 Subject: sparc64: Migrate hvcons irq to panicked cpu On panic, all other CPUs are stopped except the one which had hit panic. To keep console alive, we need to migrate hvcons irq to panicked CPU. Signed-off-by: Vijay Kumar Signed-off-by: David S. Miller --- arch/sparc/include/asm/setup.h | 5 ++++- arch/sparc/kernel/smp_64.c | 6 +++++- drivers/tty/serial/sunhv.c | 6 ++++++ 3 files changed, 15 insertions(+), 2 deletions(-) diff --git a/arch/sparc/include/asm/setup.h b/arch/sparc/include/asm/setup.h index 29d64b1758ed..478bf6bb4598 100644 --- a/arch/sparc/include/asm/setup.h +++ b/arch/sparc/include/asm/setup.h @@ -59,8 +59,11 @@ extern atomic_t dcpage_flushes; extern atomic_t dcpage_flushes_xcall; extern int sysctl_tsb_ratio; -#endif +#ifdef CONFIG_SERIAL_SUNHV +void sunhv_migrate_hvcons_irq(int cpu); +#endif +#endif void sun_do_break(void); extern int stop_a_enabled; extern int scons_pwroff; diff --git a/arch/sparc/kernel/smp_64.c b/arch/sparc/kernel/smp_64.c index 712bf1b7f630..90a02cb64e20 100644 --- a/arch/sparc/kernel/smp_64.c +++ b/arch/sparc/kernel/smp_64.c @@ -1452,8 +1452,12 @@ void smp_send_stop(void) int cpu; if (tlb_type == hypervisor) { + int this_cpu = smp_processor_id(); +#ifdef CONFIG_SERIAL_SUNHV + sunhv_migrate_hvcons_irq(this_cpu); +#endif for_each_online_cpu(cpu) { - if (cpu == smp_processor_id()) + if (cpu == this_cpu) continue; set_cpu_online(cpu, false); diff --git a/drivers/tty/serial/sunhv.c b/drivers/tty/serial/sunhv.c index 73abd89c0108..c5ebdc8bed6a 100644 --- a/drivers/tty/serial/sunhv.c +++ b/drivers/tty/serial/sunhv.c @@ -398,6 +398,12 @@ static struct uart_driver sunhv_reg = { static struct uart_port *sunhv_port; +void sunhv_migrate_hvcons_irq(int cpu) +{ + /* Migrate hvcons irq to param cpu */ + irq_force_affinity(sunhv_port->irq, cpumask_of(cpu)); +} + /* Copy 's' into the con_write_page, decoding "\n" into * "\r\n" along the way. We have to return two lengths * because the caller needs to know how much to advance -- cgit v1.2.3-70-g09d2 From 7db60d05e5ccc0a473fa2275f90f2fca0002ab21 Mon Sep 17 00:00:00 2001 From: Vijay Kumar Date: Wed, 1 Feb 2017 11:34:39 -0800 Subject: sparc64: Send break twice from console to return to boot prom Now we can also jump to boot prom from sunhv console by sending break twice on console for both running and panicked kernel cases. Signed-off-by: Vijay Kumar Signed-off-by: David S. Miller --- drivers/tty/serial/sunhv.c | 6 +++++- kernel/panic.c | 3 ++- 2 files changed, 7 insertions(+), 2 deletions(-) diff --git a/drivers/tty/serial/sunhv.c b/drivers/tty/serial/sunhv.c index c5ebdc8bed6a..46e46894e918 100644 --- a/drivers/tty/serial/sunhv.c +++ b/drivers/tty/serial/sunhv.c @@ -116,7 +116,7 @@ static int receive_chars_getchar(struct uart_port *port) static int receive_chars_read(struct uart_port *port) { - int saw_console_brk = 0; + static int saw_console_brk; int limit = 10000; while (limit-- > 0) { @@ -128,6 +128,9 @@ static int receive_chars_read(struct uart_port *port) bytes_read = 0; if (stat == CON_BREAK) { + if (saw_console_brk) + sun_do_break(); + if (uart_handle_break(port)) continue; saw_console_brk = 1; @@ -151,6 +154,7 @@ static int receive_chars_read(struct uart_port *port) if (port->sysrq != 0 && *con_read_page) { for (i = 0; i < bytes_read; i++) uart_handle_sysrq_char(port, con_read_page[i]); + saw_console_brk = 0; } if (port->state == NULL) diff --git a/kernel/panic.c b/kernel/panic.c index b95959733ce0..3ec16e603e88 100644 --- a/kernel/panic.c +++ b/kernel/panic.c @@ -273,7 +273,8 @@ void panic(const char *fmt, ...) extern int stop_a_enabled; /* Make sure the user can actually press Stop-A (L1-A) */ stop_a_enabled = 1; - pr_emerg("Press Stop-A (L1-A) to return to the boot prom\n"); + pr_emerg("Press Stop-A (L1-A) from sun keyboard or send break\n" + "twice on console to return to the boot prom\n"); } #endif #if defined(CONFIG_S390) -- cgit v1.2.3-70-g09d2 From 4cfe140618b99e653134598de9f18b48743549ec Mon Sep 17 00:00:00 2001 From: Vijay Kumar Date: Wed, 1 Feb 2017 11:34:40 -0800 Subject: Documentation/sparc: Steps for sending break on sunhv console Documented the steps for sending break on sunhv console. Signed-off-by: Vijay Kumar Signed-off-by: David S. Miller --- Documentation/sparc/console.txt | 9 +++++++++ 1 file changed, 9 insertions(+) create mode 100644 Documentation/sparc/console.txt diff --git a/Documentation/sparc/console.txt b/Documentation/sparc/console.txt new file mode 100644 index 000000000000..5aa735a44e02 --- /dev/null +++ b/Documentation/sparc/console.txt @@ -0,0 +1,9 @@ +Steps for sending 'break' on sunhv console: +=========================================== + +On Baremetal: + 1. press Esc + 'B' + +On LDOM: + 1. press Ctrl + ']' + 2. telnet> send break -- cgit v1.2.3-70-g09d2