| Message ID | 20191018043000.21033-1-oohall@gmail.com |
|---|---|
| State | Accepted |
| Headers | show |
| Series | hw/port80: Squash No SYNC error | expand |
| Context | Check | Description |
|---|---|---|
| snowpatch_ozlabs/apply_patch | success | Successfully applied on branch master (d75e82dbfbb9443efeb3f9a5921ac23605aab469) |
| snowpatch_ozlabs/snowpatch_job_snowpatch-skiboot | fail | Test snowpatch/job/snowpatch-skiboot on branch master |
| snowpatch_ozlabs/snowpatch_job_snowpatch-skiboot-dco | success | Signed-off-by present |
On Fri, 18 Oct 2019, at 15:00, Oliver O'Halloran wrote: > On Aspeed BMCs can be configured to route LPC IO address 0x80 to a GPIO > port. Some systems use this to implement a boot progress indicator, but > not all of them. > > There's no easy way to tell if this has been setup or not and if it > hasn't we get an LPC SYNC no-response error from out LPC master. When we > reach Linux and enable interrupts this results in this spurious error > being printed: > > LPC[000]: Got SYNC no-response error. Error address reg: 0xd0010082 > > lpc_probe_write() is intended to catch situations where the peripherial > being written to might not be configured, so use that instead of > lpc_outb() to squash the error. > > Cc: Ranga <stewart@flamingspork.com> > Cc: Andrew Jeffery <andrew@aj.id.au> > Signed-off-by: Oliver O'Halloran <oohall@gmail.com> > --- > Stewart, do you know what systems actually implment this feature? > Seem like you added op_display_lpc() to add the BMC systems, but > I'm guessing only a few of them actually support it. At least the Raptor systems as far as I'm aware, they needed some way to observe boot progress. Anyway, patch seems reasonable to me. Acked-by: Andrew Jeffery <andrew@aj.id.au>
> On 17 Oct 2019, at 21:30, Oliver O'Halloran <oohall@gmail.com> wrote: > > On Aspeed BMCs can be configured to route LPC IO address 0x80 to a GPIO > port. Some systems use this to implement a boot progress indicator, but > not all of them. > > There's no easy way to tell if this has been setup or not and if it > hasn't we get an LPC SYNC no-response error from out LPC master. When we > reach Linux and enable interrupts this results in this spurious error > being printed: > > LPC[000]: Got SYNC no-response error. Error address reg: 0xd0010082 > > lpc_probe_write() is intended to catch situations where the peripherial > being written to might not be configured, so use that instead of > lpc_outb() to squash the error. > > Cc: Ranga <stewart@flamingspork.com> > Cc: Andrew Jeffery <andrew@aj.id.au> > Signed-off-by: Oliver O'Halloran <oohall@gmail.com> > --- > Stewart, do you know what systems actually implment this feature? > Seem like you added op_display_lpc() to add the BMC systems, but > I'm guessing only a few of them actually support it. All the Raptor systems do, and the code has (IIRC) headed upstream to OpenBMC. Maybe should just silence the error on other systems? That was the original thought, nothing there listening = silence any error
diff --git a/hw/lpc-port80h.c b/hw/lpc-port80h.c index eb1378c8ad2b..b373af7bcc8f 100644 --- a/hw/lpc-port80h.c +++ b/hw/lpc-port80h.c @@ -164,9 +164,10 @@ void op_display_lpc(enum op_severity s, enum op_module m, uint16_t c) return; port80_val = op_display_to_port80(port80_val, s, m, c); - lpc_outb(port80_val, 0x80); port8x_val = op_display_to_port8x(port8x_val, s, m, c); - lpc_outb(port8x_val >> 8, 0x81); - lpc_outb(port8x_val & 0xFF, 0x82); + + lpc_probe_write(OPAL_LPC_IO, 0x80, port80_val, 1); + lpc_probe_write(OPAL_LPC_IO, 0x81, port8x_val >> 8, 1); + lpc_probe_write(OPAL_LPC_IO, 0x82, port8x_val & 0xff, 1); } diff --git a/hw/test/run-port80h.c b/hw/test/run-port80h.c index 85e8d8721244..4964f4836ba8 100644 --- a/hw/test/run-port80h.c +++ b/hw/test/run-port80h.c @@ -15,15 +15,18 @@ uint8_t port80; uint16_t port8x; -static inline void lpc_outb(uint8_t data, uint32_t addr) +static int64_t lpc_probe_write(int addr_type __unused, uint32_t addr, + uint32_t data, uint32_t sz) { assert((addr - 0x80) <= 2); + assert(sz == 1); if (addr == 0x80) port80 = data; if (addr == 0x81) port8x = data << 8 | (port8x & 0xff); if (addr == 0x82) port8x = (port8x & 0xff00) | data; + return 0; } #include "op-panel.h"
On Aspeed BMCs can be configured to route LPC IO address 0x80 to a GPIO port. Some systems use this to implement a boot progress indicator, but not all of them. There's no easy way to tell if this has been setup or not and if it hasn't we get an LPC SYNC no-response error from out LPC master. When we reach Linux and enable interrupts this results in this spurious error being printed: LPC[000]: Got SYNC no-response error. Error address reg: 0xd0010082 lpc_probe_write() is intended to catch situations where the peripherial being written to might not be configured, so use that instead of lpc_outb() to squash the error. Cc: Ranga <stewart@flamingspork.com> Cc: Andrew Jeffery <andrew@aj.id.au> Signed-off-by: Oliver O'Halloran <oohall@gmail.com> --- Stewart, do you know what systems actually implment this feature? Seem like you added op_display_lpc() to add the BMC systems, but I'm guessing only a few of them actually support it. --- hw/lpc-port80h.c | 7 ++++--- hw/test/run-port80h.c | 5 ++++- 2 files changed, 8 insertions(+), 4 deletions(-)