usbdebug: Block recursive calls of printk

When we create low-level debugging of EHCI controller registers,
we call printk() within printk(). In ramstage this would leave us
with deadlock waiting on the console spinlock.

Change-Id: Idbe029af9af76de27094bb2964c60d9ccfdd96e6
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: http://review.coreboot.org/3860
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
This commit is contained in:
Kyösti Mälkki 2013-08-12 16:11:34 +03:00
parent 8ff3d68e93
commit d79914008a
1 changed files with 44 additions and 10 deletions

View File

@ -33,6 +33,7 @@
#define DBGP_EP_VALID (1<<0)
#define DBGP_EP_ENABLED (1<<1)
#define DBGP_EP_BUSY (1<<2)
#define DBGP_EP_STATMASK (DBGP_EP_VALID | DBGP_EP_ENABLED)
struct dbgp_pipe
@ -44,8 +45,9 @@ struct dbgp_pipe
};
#define DBGP_MAX_ENDPOINTS 4
#define DBGP_CONSOLE_EPOUT 0
#define DBGP_CONSOLE_EPIN 1
#define DBGP_SETUP_EP0 0 /* Compulsory endpoint 0. */
#define DBGP_CONSOLE_EPOUT 1
#define DBGP_CONSOLE_EPIN 2
struct ehci_debug_info {
u8 devnum;
@ -58,7 +60,9 @@ struct ehci_debug_info {
};
#if CONFIG_DEBUG_USBDEBUG
# define dprintk(LEVEL, args...) printk(LEVEL, args)
static int dbgp_enabled(void);
# define dprintk(LEVEL, args...) \
do { if (!dbgp_enabled()) printk(LEVEL, ##args); } while (0)
#else
# define dprintk(LEVEL, args...) do {} while(0)
#endif
@ -580,6 +584,7 @@ try_next_port:
info->ep_pipe[DBGP_CONSOLE_EPOUT].endpoint = dbgp_desc.bDebugOutEndpoint;
info->ep_pipe[DBGP_CONSOLE_EPIN].endpoint = dbgp_desc.bDebugInEndpoint;
info->ep_pipe[DBGP_SETUP_EP0].status |= DBGP_EP_ENABLED | DBGP_EP_VALID;
info->ep_pipe[DBGP_CONSOLE_EPOUT].status |= DBGP_EP_ENABLED | DBGP_EP_VALID;
info->ep_pipe[DBGP_CONSOLE_EPIN].status |= DBGP_EP_ENABLED | DBGP_EP_VALID;
return 0;
@ -606,23 +611,52 @@ next_debug_port:
return -10;
}
#if CONFIG_DEBUG_USBDEBUG
static int dbgp_enabled(void)
{
struct dbgp_pipe *globals = &dbgp_ehci_info()->ep_pipe[DBGP_SETUP_EP0];
return (globals->status & DBGP_EP_ENABLED);
}
#endif
static int dbgp_try_get(struct dbgp_pipe *pipe)
{
struct dbgp_pipe *globals = &dbgp_ehci_info()->ep_pipe[DBGP_SETUP_EP0];
if (!dbgp_ep_is_active(pipe) || (globals->status & DBGP_EP_BUSY))
return 0;
globals->status |= DBGP_EP_BUSY;
pipe->status |= DBGP_EP_BUSY;
return 1;
}
static void dbgp_put(struct dbgp_pipe *pipe)
{
struct dbgp_pipe *globals = &dbgp_ehci_info()->ep_pipe[DBGP_SETUP_EP0];
globals->status &= ~DBGP_EP_BUSY;
pipe->status &= ~DBGP_EP_BUSY;
}
void usbdebug_tx_byte(struct dbgp_pipe *pipe, unsigned char data)
{
if (dbgp_ep_is_active(pipe)) {
pipe->buf[pipe->bufidx++] = data;
if (pipe->bufidx >= 8) {
dbgp_bulk_write_x(pipe, pipe->buf, pipe->bufidx);
pipe->bufidx = 0;
}
if (!dbgp_try_get(pipe))
return;
pipe->buf[pipe->bufidx++] = data;
if (pipe->bufidx >= 8) {
dbgp_bulk_write_x(pipe, pipe->buf, pipe->bufidx);
pipe->bufidx = 0;
}
dbgp_put(pipe);
}
void usbdebug_tx_flush(struct dbgp_pipe *pipe)
{
if (dbgp_ep_is_active(pipe) && pipe->bufidx > 0) {
if (!dbgp_try_get(pipe))
return;
if (pipe->bufidx > 0) {
dbgp_bulk_write_x(pipe, pipe->buf, pipe->bufidx);
pipe->bufidx = 0;
}
dbgp_put(pipe);
}
#if !defined(__PRE_RAM__) && !defined(__SMM__)