xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

powerpc/powernv: Support for OPAL console

Browse Source 
This adds a udbg and an hvc console backend for supporting a console
using the OPAL console interfaces.

On OPAL v1 we have hvc0 mapped to whatever console the system was
configured for (network or hvsi serial port) via the service
processor.

On OPAL v2 we have hvcN mapped to the Nth console provided by OPAL
which generally corresponds to:

	hvc0 : network console (raw protocol)
	hvc1 : serial port S1 (hvsi)
	hvc2 : serial port S2 (hvsi)

Note: At this point, early debug console only works with OPAL v1
and shouldn't be enabled in a normal kernel.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This commit is contained in:
Benjamin Herrenschmidt
2011-09-19 17:44:59 +00:00
parent 6e35d5dac0
commit daea1175a9
11 changed files with 517 additions and 22 deletions
Download Patch File Download Diff File Expand all files Collapse all files

31
arch/powerpc/platforms/powernv/opal.c
View File

@@ -67,7 +67,7 @@ int opal_get_chars(uint32_t vtermno, char *buf, int count)
u64 evt;
if (!opal.entry)
return 0;
return -ENODEV;
opal_poll_events(&evt);
if ((evt & OPAL_EVENT_CONSOLE_INPUT) == 0)
return 0;
@@ -81,31 +81,38 @@ int opal_get_chars(uint32_t vtermno, char *buf, int count)
int opal_put_chars(uint32_t vtermno, const char *data, int total_len)
{
int written = 0;
s64 len, rc = OPAL_BUSY;
s64 len, rc;
unsigned long flags;
u64 evt;
if (!opal.entry)
return 0;
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
* -EAGAIN if there isn't enough.
*
* Unfortunately, opal_console_write_buffer_space() doesn't
* appear to work on opal v1, so we just assume there is
* enough room and be done with it
*/
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;
if (firmware_has_feature(FW_FEATURE_OPALv2)) {
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.
*/
rc = OPAL_BUSY;
while(total_len > 0 && (rc == OPAL_BUSY ||
rc == OPAL_BUSY_EVENT || rc == OPAL_SUCCESS)) {
len = total_len;