diff options
Diffstat (limited to 'arch/powerpc/platforms/powernv/opal.c')
-rw-r--r-- | arch/powerpc/platforms/powernv/opal.c | 154 |
1 files changed, 154 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/powernv/opal.c b/arch/powerpc/platforms/powernv/opal.c new file mode 100644 index 00000000000..8d5510784cc --- /dev/null +++ b/arch/powerpc/platforms/powernv/opal.c @@ -0,0 +1,154 @@ +/* + * PowerNV OPAL high level interfaces + * + * Copyright 2011 IBM Corp. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + +#undef DEBUG + +#include <linux/types.h> +#include <linux/of.h> +#include <linux/of_platform.h> +#include <asm/opal.h> +#include <asm/firmware.h> + +#include "powernv.h" + +struct opal { + u64 base; + u64 entry; +} opal; + +static struct device_node *opal_node; +static DEFINE_SPINLOCK(opal_write_lock); + +int __init early_init_dt_scan_opal(unsigned long node, + const char *uname, int depth, void *data) +{ + const void *basep, *entryp; + unsigned long basesz, entrysz; + + if (depth != 1 || strcmp(uname, "ibm,opal") != 0) + return 0; + + basep = of_get_flat_dt_prop(node, "opal-base-address", &basesz); + entryp = of_get_flat_dt_prop(node, "opal-entry-address", &entrysz); + + if (!basep || !entryp) + return 1; + + opal.base = of_read_number(basep, basesz/4); + opal.entry = of_read_number(entryp, entrysz/4); + + pr_debug("OPAL Base = 0x%llx (basep=%p basesz=%ld)\n", + opal.base, basep, basesz); + pr_debug("OPAL Entry = 0x%llx (entryp=%p basesz=%ld)\n", + opal.entry, entryp, entrysz); + + powerpc_firmware_features |= FW_FEATURE_OPAL; + if (of_flat_dt_is_compatible(node, "ibm,opal-v2")) { + powerpc_firmware_features |= FW_FEATURE_OPALv2; + printk("OPAL V2 detected !\n"); + } else { + printk("OPAL V1 detected !\n"); + } + + return 1; +} + +int opal_get_chars(uint32_t vtermno, char *buf, int count) +{ + s64 len, rc; + u64 evt; + + if (!opal.entry) + return 0; + opal_poll_events(&evt); + if ((evt & OPAL_EVENT_CONSOLE_INPUT) == 0) + return 0; + len = count; + rc = opal_console_read(vtermno, &len, buf); + if (rc == OPAL_SUCCESS) + return len; + return 0; +} + +int opal_put_chars(uint32_t vtermno, const char *data, int total_len) +{ + int written = 0; + s64 len, rc = OPAL_BUSY; + unsigned long flags; + u64 evt; + + if (!opal.entry) + return 0; + + /* 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); + rc = opal_console_write_buffer_space(vtermno, &len); + if (rc || len < total_len) { + spin_unlock_irqrestore(&opal_write_lock, flags); + /* Closed -> drop characters */ + if (rc) + return total_len; + opal_poll_events(&evt); + return -EAGAIN; + } + + /* We still try to handle partial completions, though they + * should no longer happen. + */ + while(total_len > 0 && (rc == OPAL_BUSY || + rc == OPAL_BUSY_EVENT || rc == OPAL_SUCCESS)) { + len = total_len; + rc = opal_console_write(vtermno, &len, data); + if (rc == OPAL_SUCCESS) { + total_len -= len; + data += len; + written += len; + } + /* This is a bit nasty but we need that for the console to + * flush when there aren't any interrupts. We will clean + * things a bit later to limit that to synchronous path + * such as the kernel console and xmon/udbg + */ + do + opal_poll_events(&evt); + while(rc == OPAL_SUCCESS && (evt & OPAL_EVENT_CONSOLE_OUTPUT)); + } + spin_unlock_irqrestore(&opal_write_lock, flags); + return written; +} + +static int __init opal_init(void) +{ + struct device_node *np, *consoles; + + opal_node = of_find_node_by_path("/ibm,opal"); + if (!opal_node) { + pr_warn("opal: Node not found\n"); + return -ENODEV; + } + if (firmware_has_feature(FW_FEATURE_OPALv2)) + consoles = of_find_node_by_path("/ibm,opal/consoles"); + else + consoles = of_node_get(opal_node); + + /* Register serial ports */ + for_each_child_of_node(consoles, np) { + if (strcmp(np->name, "serial")) + continue; + of_platform_device_create(np, NULL, NULL); + } + of_node_put(consoles); + return 0; +} +subsys_initcall(opal_init); |