On AMD-Xilinx platforms cortex-A and cortex-R can be configured as separate subsystems. In this case, both cores can boot independent of each other. If Linux went through uncontrolled reboot during active rpmsg communication, then during next boot it can find rpmsg virtio status not in the reset state. In such case it is important to reset the virtio status during attach callback and wait for sometime for the remote to handle virtio driver reset.
Signed-off-by: Tanmay Shah <[email protected]> --- drivers/remoteproc/xlnx_r5_remoteproc.c | 46 +++++++++++++++++++++++++ 1 file changed, 46 insertions(+) diff --git a/drivers/remoteproc/xlnx_r5_remoteproc.c b/drivers/remoteproc/xlnx_r5_remoteproc.c index 50a9974f3202..f08806f13800 100644 --- a/drivers/remoteproc/xlnx_r5_remoteproc.c +++ b/drivers/remoteproc/xlnx_r5_remoteproc.c @@ -5,6 +5,7 @@ */ #include <dt-bindings/power/xlnx-zynqmp-power.h> +#include <linux/delay.h> #include <linux/dma-mapping.h> #include <linux/firmware/xlnx-zynqmp.h> #include <linux/kernel.h> @@ -29,6 +30,8 @@ #define RSC_TBL_XLNX_MAGIC ((uint32_t)'x' << 24 | (uint32_t)'a' << 16 | \ (uint32_t)'m' << 8 | (uint32_t)'p') +#define RPROC_ATTACH_TIMEOUT_US (100 * 1000) + /* * settings for RPU cluster mode which * reflects possible values of xlnx,cluster-mode dt-property @@ -865,6 +868,49 @@ static int zynqmp_r5_get_rsc_table_va(struct zynqmp_r5_core *r5_core) static int zynqmp_r5_attach(struct rproc *rproc) { + struct device *dev = &rproc->dev; + bool wait_for_remote = false; + struct fw_rsc_vdev *rsc; + struct fw_rsc_hdr *hdr; + int i, offset, avail; + + if (!rproc->table_ptr) + goto attach_success; + + for (i = 0; i < rproc->table_ptr->num; i++) { + offset = rproc->table_ptr->offset[i]; + hdr = (void *)rproc->table_ptr + offset; + avail = rproc->table_sz - offset - sizeof(*hdr); + rsc = (void *)hdr + sizeof(*hdr); + + /* make sure table isn't truncated */ + if (avail < 0) { + dev_err(dev, "rsc table is truncated\n"); + return -EINVAL; + } + + if (hdr->type != RSC_VDEV) + continue; + + /* + * reset vdev status, in case previous run didn't leave it in + * a clean state. + */ + if (rsc->status) { + rsc->status = 0; + wait_for_remote = true; + break; + } + } + + /* kick remote to notify about attach */ + rproc->ops->kick(rproc, 0); + + /* wait for sometime until remote is ready */ + if (wait_for_remote) + usleep_range(100, RPROC_ATTACH_TIMEOUT_US); + +attach_success: dev_dbg(&rproc->dev, "rproc %d attached\n", rproc->index); return 0; base-commit: d4ef36fbd57e610d4c334123ce706a2a71187cae -- 2.34.1
