diff options
| -rw-r--r-- | arch/powerpc/include/asm/opal.h | 1 | ||||
| -rw-r--r-- | arch/powerpc/platforms/powernv/opal.c | 37 | ||||
| -rw-r--r-- | drivers/tty/hvc/hvc_opal.c | 18 |
3 files changed, 41 insertions, 15 deletions
diff --git a/arch/powerpc/include/asm/opal.h b/arch/powerpc/include/asm/opal.h index 33ab95a4ac0f..cd1acc8be8ee 100644 --- a/arch/powerpc/include/asm/opal.h +++ b/arch/powerpc/include/asm/opal.h @@ -305,6 +305,7 @@ extern void opal_configure_cores(void); extern int opal_get_chars(uint32_t vtermno, char *buf, int count); extern int opal_put_chars(uint32_t vtermno, const char *buf, int total_len); +extern int opal_put_chars_atomic(uint32_t vtermno, const char *buf, int total_len); extern int opal_flush_console(uint32_t vtermno); extern void hvc_opal_init_early(void); diff --git a/arch/powerpc/platforms/powernv/opal.c b/arch/powerpc/platforms/powernv/opal.c index cf02e602237a..6405b6f20193 100644 --- a/arch/powerpc/platforms/powernv/opal.c +++ b/arch/powerpc/platforms/powernv/opal.c @@ -344,9 +344,9 @@ int opal_get_chars(uint32_t vtermno, char *buf, int count) return 0; } -int opal_put_chars(uint32_t vtermno, const char *data, int total_len) +static int __opal_put_chars(uint32_t vtermno, const char *data, int total_len, bool atomic) { - unsigned long flags; + unsigned long flags = 0 /* shut up gcc */; int written; __be64 olen; s64 rc; @@ -354,11 +354,8 @@ int opal_put_chars(uint32_t vtermno, const char *data, int total_len) if (!opal.entry) return -ENODEV; - /* We want put_chars to be atomic to avoid mangling of hvsi - * packets. To do that, we first test for room and return - * -EAGAIN if there isn't enough. - */ - spin_lock_irqsave(&opal_write_lock, flags); + if (atomic) + spin_lock_irqsave(&opal_write_lock, flags); rc = opal_console_write_buffer_space(vtermno, &olen); if (rc || be64_to_cpu(olen) < total_len) { /* Closed -> drop characters */ @@ -391,14 +388,18 @@ int opal_put_chars(uint32_t vtermno, const char *data, int total_len) written = be64_to_cpu(olen); if (written < total_len) { - /* Should not happen */ - pr_warn("atomic console write returned partial len=%d written=%d\n", total_len, written); + if (atomic) { + /* Should not happen */ + pr_warn("atomic console write returned partial " + "len=%d written=%d\n", total_len, written); + } if (!written) written = -EAGAIN; } out: - spin_unlock_irqrestore(&opal_write_lock, flags); + if (atomic) + spin_unlock_irqrestore(&opal_write_lock, flags); /* In the -EAGAIN case, callers loop, so we have to flush the console * here in case they have interrupts off (and we don't want to wait @@ -412,6 +413,22 @@ out: return written; } +int opal_put_chars(uint32_t vtermno, const char *data, int total_len) +{ + return __opal_put_chars(vtermno, data, total_len, false); +} + +/* + * opal_put_chars_atomic will not perform partial-writes. Data will be + * atomically written to the terminal or not at all. This is not strictly + * true at the moment because console space can race with OPAL's console + * writes. + */ +int opal_put_chars_atomic(uint32_t vtermno, const char *data, int total_len) +{ + return __opal_put_chars(vtermno, data, total_len, true); +} + int opal_flush_console(uint32_t vtermno) { s64 rc; diff --git a/drivers/tty/hvc/hvc_opal.c b/drivers/tty/hvc/hvc_opal.c index 958c61c8f35a..810fd42904c3 100644 --- a/drivers/tty/hvc/hvc_opal.c +++ b/drivers/tty/hvc/hvc_opal.c @@ -183,9 +183,15 @@ static int hvc_opal_probe(struct platform_device *dev) return -ENOMEM; pv->proto = proto; hvc_opal_privs[termno] = pv; - if (proto == HV_PROTOCOL_HVSI) - hvsilib_init(&pv->hvsi, opal_get_chars, opal_put_chars, + if (proto == HV_PROTOCOL_HVSI) { + /* + * We want put_chars to be atomic to avoid mangling of + * hvsi packets. + */ + hvsilib_init(&pv->hvsi, + opal_get_chars, opal_put_chars_atomic, termno, 0); + } /* Instanciate now to establish a mapping index==vtermno */ hvc_instantiate(termno, termno, ops); @@ -375,8 +381,9 @@ void __init hvc_opal_init_early(void) else if (of_device_is_compatible(stdout_node,"ibm,opal-console-hvsi")) { hvc_opal_boot_priv.proto = HV_PROTOCOL_HVSI; ops = &hvc_opal_hvsi_ops; - hvsilib_init(&hvc_opal_boot_priv.hvsi, opal_get_chars, - opal_put_chars, index, 1); + hvsilib_init(&hvc_opal_boot_priv.hvsi, + opal_get_chars, opal_put_chars_atomic, + index, 1); /* HVSI, perform the handshake now */ hvsilib_establish(&hvc_opal_boot_priv.hvsi); pr_devel("hvc_opal: Found HVSI console\n"); @@ -408,7 +415,8 @@ void __init udbg_init_debug_opal_hvsi(void) hvc_opal_privs[index] = &hvc_opal_boot_priv; hvc_opal_boot_termno = index; udbg_init_opal_common(); - hvsilib_init(&hvc_opal_boot_priv.hvsi, opal_get_chars, opal_put_chars, + hvsilib_init(&hvc_opal_boot_priv.hvsi, + opal_get_chars, opal_put_chars_atomic, index, 1); hvsilib_establish(&hvc_opal_boot_priv.hvsi); } |