diff options
Diffstat (limited to 'drivers/misc/cbmem_console.c')
-rw-r--r-- | drivers/misc/cbmem_console.c | 43 |
1 files changed, 26 insertions, 17 deletions
diff --git a/drivers/misc/cbmem_console.c b/drivers/misc/cbmem_console.c index 8bbe33d414..ba3a599c4a 100644 --- a/drivers/misc/cbmem_console.c +++ b/drivers/misc/cbmem_console.c @@ -5,27 +5,37 @@ #include <common.h> #include <console.h> -#ifndef CONFIG_SYS_COREBOOT -#error This driver requires coreboot -#endif - #include <asm/cb_sysinfo.h> -struct cbmem_console { - u32 buffer_size; - u32 buffer_cursor; - u8 buffer_body[0]; -} __attribute__ ((__packed__)); - -static struct cbmem_console *cbmem_console_p; - void cbmemc_putc(struct stdio_dev *dev, char data) { - int cursor; + const struct sysinfo_t *sysinfo = cb_get_sysinfo(); + struct cbmem_console *cons; + uint pos, flags; + + if (!sysinfo) + return; + cons = sysinfo->cbmem_cons; + if (!cons) + return; + + pos = cons->cursor & CBMC_CURSOR_MASK; + + /* preserve the overflow flag if present */ + flags = cons->cursor & ~CBMC_CURSOR_MASK; + + cons->body[pos++] = data; + + /* + * Deal with overflow - the flag may be cleared by another program which + * reads the buffer out later, e.g. Linux + */ + if (pos >= cons->size) { + pos = 0; + flags |= CBMC_OVERFLOW; + } - cursor = cbmem_console_p->buffer_cursor++; - if (cursor < cbmem_console_p->buffer_size) - cbmem_console_p->buffer_body[cursor] = data; + cons->cursor = flags | pos; } void cbmemc_puts(struct stdio_dev *dev, const char *str) @@ -40,7 +50,6 @@ int cbmemc_init(void) { int rc; struct stdio_dev cons_dev; - cbmem_console_p = lib_sysinfo.cbmem_cons; memset(&cons_dev, 0, sizeof(cons_dev)); |