On Thu, Feb 26, 2015 at 09:11:07PM -0600, Michael Roth wrote: > This interface is used to fetch an OF device-tree nodes that describes a > newly-attached device to guest. It is called multiple times to walk the > device-tree node and fetch individual properties into a 'workarea'/buffer > provided by the guest. > > The device-tree is generated by QEMU and passed to an sPAPRDRConnector during > the initial hotplug operation, and the state of these RTAS calls is tracked by > the sPAPRDRConnector. When the last of these properties is successfully > fetched, we report as special return value to the guest and transition > the device to a 'configured' state on the QEMU/DRC side. > > See docs/specs/ppc-spapr-hotplug.txt for a complete description of > this interface. > > Signed-off-by: Michael Roth <mdr...@linux.vnet.ibm.com>
So, actually, here's probably the best place to explain what I had in
mind for changing the internal interface for this stuff. I was
thinking something like this pseudocode:
struct DRCCCState {
void *fdt;
int offset;
int depth;
};
rtas_configure_connector()
{
...
DRCCCState *ccstate;
...
/* check parameters, retrieve drc */
ccstate = drc->ccstate;
if (!ccstate) {
/* Haven't started configuring yet */
ccstate = malloc(...);
/* Retrieve the dt fragment from the backend */
ccstate->fdt = drck->get_dt(...);
ccstate->offset = 0;
}
while (get next tag from fdt) {
switch (tag)
case FDT_PROPERTY:
/* Translate property into rtas return values */
return SPAPR_DR_CC_RESPONSE_NEXT_PROPERTY;
/* other cases ... */
}
/* Fall through only if we've completed streaming out the dt
*/
/* Tell the back end we've finished configuring */
drck->cc_completed(...);
return SPAPR_DR_CC_RESPONSE_SUCCESS;
}
On reset, or anything else which interrupts the configuration process,
just blow away drc->ccstate.
> ---
> hw/ppc/spapr_rtas.c | 88
> +++++++++++++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 88 insertions(+)
>
> diff --git a/hw/ppc/spapr_rtas.c b/hw/ppc/spapr_rtas.c
> index f80beb2..31ad35f 100644
> --- a/hw/ppc/spapr_rtas.c
> +++ b/hw/ppc/spapr_rtas.c
> @@ -418,6 +418,92 @@ static void rtas_get_sensor_state(PowerPCCPU *cpu,
> sPAPREnvironment *spapr,
> rtas_st(rets, 1, entity_sense);
> }
>
> +/* configure-connector work area offsets, int32_t units for field
> + * indexes, bytes for field offset/len values.
> + *
> + * as documented by PAPR+ v2.7, 13.5.3.5
> + */
> +#define CC_IDX_NODE_NAME_OFFSET 2
> +#define CC_IDX_PROP_NAME_OFFSET 2
> +#define CC_IDX_PROP_LEN 3
> +#define CC_IDX_PROP_DATA_OFFSET 4
> +#define CC_VAL_DATA_OFFSET ((CC_IDX_PROP_DATA_OFFSET + 1) * 4)
> +#define CC_WA_LEN 4096
> +
> +static void rtas_ibm_configure_connector(PowerPCCPU *cpu,
> + sPAPREnvironment *spapr,
> + uint32_t token, uint32_t nargs,
> + target_ulong args, uint32_t nret,
> + target_ulong rets)
> +{
> + uint64_t wa_addr;
> + uint64_t wa_offset;
> + uint32_t drc_index;
> + sPAPRDRConnector *drc;
> + sPAPRDRConnectorClass *drck;
> + sPAPRDRCCResponse resp;
> + const struct fdt_property *prop = NULL;
> + char *prop_name = NULL;
> + int prop_len, rc;
> +
> + if (nargs != 2 || nret != 1) {
> + rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR);
> + return;
> + }
> +
> + wa_addr = ((uint64_t)rtas_ld(args, 1) << 32) | rtas_ld(args, 0);
> +
> + drc_index = rtas_ld(wa_addr, 0);
> + drc = spapr_dr_connector_by_index(drc_index);
> + if (!drc) {
> + DPRINTF("rtas_ibm_configure_connector: invalid sensor/DRC index:
> %xh\n",
> + drc_index);
> + rc = RTAS_OUT_PARAM_ERROR;
> + goto out;
> + }
> + drck = SPAPR_DR_CONNECTOR_GET_CLASS(drc);
> + resp = drck->configure_connector(drc, &prop_name, &prop, &prop_len);
> +
> + switch (resp) {
> + case SPAPR_DR_CC_RESPONSE_NEXT_CHILD:
> + /* provide the name of the next OF node */
> + wa_offset = CC_VAL_DATA_OFFSET;
> + rtas_st(wa_addr, CC_IDX_NODE_NAME_OFFSET, wa_offset);
> + rtas_st_buffer_direct(wa_addr + wa_offset, CC_WA_LEN - wa_offset,
> + (uint8_t *)prop_name, strlen(prop_name) + 1);
> + break;
> + case SPAPR_DR_CC_RESPONSE_NEXT_PROPERTY:
> + /* provide the name of the next OF property */
> + wa_offset = CC_VAL_DATA_OFFSET;
> + rtas_st(wa_addr, CC_IDX_PROP_NAME_OFFSET, wa_offset);
> + rtas_st_buffer_direct(wa_addr + wa_offset, CC_WA_LEN - wa_offset,
> + (uint8_t *)prop_name, strlen(prop_name) + 1);
> +
> + /* provide the length and value of the OF property. data gets placed
> + * immediately after NULL terminator of the OF property's name string
> + */
> + wa_offset += strlen(prop_name) + 1,
> + rtas_st(wa_addr, CC_IDX_PROP_LEN, prop_len);
> + rtas_st(wa_addr, CC_IDX_PROP_DATA_OFFSET, wa_offset);
> + rtas_st_buffer_direct(wa_addr + wa_offset, CC_WA_LEN - wa_offset,
> + (uint8_t *)((struct fdt_property *)prop)->data,
> + prop_len);
> + break;
> + case SPAPR_DR_CC_RESPONSE_PREV_PARENT:
> + case SPAPR_DR_CC_RESPONSE_ERROR:
> + case SPAPR_DR_CC_RESPONSE_SUCCESS:
> + break;
> + default:
> + /* drck->configure_connector() should not return anything else */
> + g_assert(false);
> + }
> +
> + rc = resp;
> +out:
> + g_free(prop_name);
> + rtas_st(rets, 0, rc);
> +}
> +
> static struct rtas_call {
> const char *name;
> spapr_rtas_fn fn;
> @@ -551,6 +637,8 @@ static void core_rtas_register_types(void)
> rtas_set_indicator);
> spapr_rtas_register(RTAS_GET_SENSOR_STATE, "get-sensor-state",
> rtas_get_sensor_state);
> + spapr_rtas_register(RTAS_IBM_CONFIGURE_CONNECTOR,
> "ibm,configure-connector",
> + rtas_ibm_configure_connector);
> }
>
> type_init(core_rtas_register_types)
--
David Gibson | I'll have my music baroque, and my code
david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_
| _way_ _around_!
http://www.ozlabs.org/~dgibson
pgp0EkeP7HfP2.pgp
Description: PGP signature
