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46abe13b5e
This transport enables communications with an SCMI platform through virtio; the SCMI platform will be represented by a virtio device. Implement an SCMI virtio driver according to the virtio SCMI device spec [1]. Virtio device id 32 has been reserved for the SCMI device [2]. The virtio transport has one Tx channel (virtio cmdq, A2P channel) and at most one Rx channel (virtio eventq, P2A channel). The following feature bit defined in [1] is not implemented: VIRTIO_SCMI_F_SHARED_MEMORY. The number of messages which can be pending simultaneously is restricted according to the virtqueue capacity negotiated at probing time. As soon as Rx channel message buffers are allocated or have been read out by the arm-scmi driver, feed them back to the virtio device. Since some virtio devices may not have the short response time exhibited by SCMI platforms using other transports, set a generous response timeout. SCMI polling mode is not supported by this virtio transport since deemed meaningless: polling mode operation is offered by the SCMI core to those transports that could not provide a completion interrupt on the TX path, which is never the case for virtio whose core callbacks can easily call into core scmi_rx_callback upon messages reception. [1] https://github.com/oasis-tcs/virtio-spec/blob/master/virtio-scmi.tex [2] https://www.oasis-open.org/committees/ballot.php?id=3496 Link: https://lore.kernel.org/r/20210803131024.40280-16-cristian.marussi@arm.com Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Co-developed-by: Peter Hilber <peter.hilber@opensynergy.com> Co-developed-by: Cristian Marussi <cristian.marussi@arm.com> Signed-off-by: Igor Skalkin <igor.skalkin@opensynergy.com> [ Peter: Adapted patch for submission to upstream. ] Signed-off-by: Peter Hilber <peter.hilber@opensynergy.com> [ Cristian: simplified driver logic, changed link_supplier and channel available/setup logic, removed dummy callbacks ] Signed-off-by: Cristian Marussi <cristian.marussi@arm.com> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> |
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| .. | ||
| arm_ffa | ||
| arm_scmi | ||
| broadcom | ||
| efi | ||
| imx | ||
| meson | ||
| psci | ||
| smccc | ||
| tegra | ||
| xilinx | ||
| arm_scpi.c | ||
| arm_sdei.c | ||
| dmi-id.c | ||
| dmi-sysfs.c | ||
| dmi_scan.c | ||
| edd.c | ||
| iscsi_ibft.c | ||
| iscsi_ibft_find.c | ||
| Kconfig | ||
| Makefile | ||
| memmap.c | ||
| pcdp.c | ||
| pcdp.h | ||
| qcom_scm-legacy.c | ||
| qcom_scm-smc.c | ||
| qcom_scm.c | ||
| qcom_scm.h | ||
| qemu_fw_cfg.c | ||
| raspberrypi.c | ||
| scpi_pm_domain.c | ||
| stratix10-rsu.c | ||
| stratix10-svc.c | ||
| ti_sci.c | ||
| ti_sci.h | ||
| trusted_foundations.c | ||
| turris-mox-rwtm.c | ||