diff options
author | David S. Miller <davem@davemloft.net> | 2017-02-23 08:27:30 -0800 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2017-02-23 08:27:30 -0800 |
commit | 0d88b86694e0b176c1b9ca10cee95863065e2471 (patch) | |
tree | 9637fa692398887c369983b5fba391b3c83c199a | |
parent | f41e54616ca1a199f6c17228f26082ccdaaab3de (diff) | |
parent | 4cfe140618b99e653134598de9f18b48743549ec (diff) |
Merge branch 'sparc64-jump-to-boot-prom'
Vijay Kumar says:
====================
sparc64: Jump to boot prom from console on panic
V3 changes:
- patch 02/04: Added SERIAL_SUNHV conditional group for
sunhv_migrate_hvcons_irq in smp_send_stop().
V2 changes:
- Added cover letter patch
Currently Stop-A (L1A) does not make the kernel switch to OBP on panic. This
patchset addresses this issue. Also, now we can cause a jump to OBP by sending
'break' twice from sunhv console. On bare metal, one can send a break by
typing Esc + 'B' + Sysrq (or whatever). On LDOM, press Ctrl + ] in telnet,
and then "send break" at the telnet prompt.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
-rw-r--r-- | Documentation/sparc/console.txt | 9 | ||||
-rw-r--r-- | arch/sparc/include/asm/setup.h | 5 | ||||
-rw-r--r-- | arch/sparc/kernel/smp_64.c | 9 | ||||
-rw-r--r-- | drivers/tty/serial/sunhv.c | 12 | ||||
-rw-r--r-- | kernel/panic.c | 3 |
5 files changed, 34 insertions, 4 deletions
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 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 0ce347f8e4cc..90a02cb64e20 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(); } @@ -1451,9 +1452,15 @@ 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); #ifdef CONFIG_SUN_LDOMS if (ldom_domaining_enabled) { unsigned long hv_err; diff --git a/drivers/tty/serial/sunhv.c b/drivers/tty/serial/sunhv.c index 73abd89c0108..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) @@ -398,6 +402,12 @@ 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 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) |