On Wed, Aug 28, 2019 at 03:03:02AM +0000, Peng Fan wrote: > From: Peng Fan <peng.fan@xxxxxxx> > > This mailbox driver implements a mailbox which signals transmitted data > via an ARM smc (secure monitor call) instruction. The mailbox receiver > is implemented in firmware and can synchronously return data when it > returns execution to the non-secure world again. > An asynchronous receive path is not implemented. > This allows the usage of a mailbox to trigger firmware actions on SoCs > which either don't have a separate management processor or on which such > a core is not available. A user of this mailbox could be the SCP > interface. > > Modified from Andre Przywara's v2 patch > https://lore.kernel.org/patchwork/patch/812999/ > > Cc: Andre Przywara <andre.przywara@xxxxxxx> > Signed-off-by: Peng Fan <peng.fan@xxxxxxx> > --- > drivers/mailbox/Kconfig | 7 ++ > drivers/mailbox/Makefile | 2 + > drivers/mailbox/arm-smc-mailbox.c | 215 ++++++++++++++++++++++++++++++++++++++ > 3 files changed, 224 insertions(+) > create mode 100644 drivers/mailbox/arm-smc-mailbox.c > [...] > +static int arm_smc_mbox_probe(struct platform_device *pdev) > +{ > + struct device *dev = &pdev->dev; > + struct mbox_controller *mbox; > + struct arm_smc_chan_data *chan_data; > + const char *method; > + bool mem_trans = false; > + int ret, i; > + u32 val; > + > + if (!of_property_read_u32(dev->of_node, "arm,num-chans", &val)) { > + if (!val) { > + dev_err(dev, "invalid arm,num-chans value %u\n", val); > + return -EINVAL; > + } > + } else { > + return -EINVAL; > + } > + > + if (!of_property_read_string(dev->of_node, "transports", &method)) { > + if (!strcmp("mem", method)) { > + mem_trans = true; > + } else if (!strcmp("reg", method)) { > + mem_trans = false; > + } else { > + dev_warn(dev, "invalid \"transports\" property: %s\n", > + method); > + > + return -EINVAL; > + } > + } else { > + return -EINVAL; > + } > + > + if (!of_property_read_string(dev->of_node, "method", &method)) { > + if (!strcmp("hvc", method)) { > + invoke_smc_mbox_fn = __invoke_fn_hvc; > + } else if (!strcmp("smc", method)) { > + invoke_smc_mbox_fn = __invoke_fn_smc; > + } else { > + dev_warn(dev, "invalid \"method\" property: %s\n", > + method); > + > + return -EINVAL; > + } > + } else { > + return -EINVAL; > + } > + > + mbox = devm_kzalloc(dev, sizeof(*mbox), GFP_KERNEL); > + if (!mbox) > + return -ENOMEM; > + > + mbox->num_chans = val; > + mbox->chans = devm_kcalloc(dev, mbox->num_chans, sizeof(*mbox->chans), > + GFP_KERNEL); > + if (!mbox->chans) > + return -ENOMEM; > + > + chan_data = devm_kcalloc(dev, mbox->num_chans, sizeof(*chan_data), > + GFP_KERNEL); > + if (!chan_data) > + return -ENOMEM; > + > + for (i = 0; i < mbox->num_chans; i++) { > + u32 function_id; > + > + ret = of_property_read_u32_index(dev->of_node, > + "arm,func-ids", i, > + &function_id); I missed it in binding but I thought we agreed to make this "arm,func-ids" a required property and not optional ? -- Regards, Sudeep