> Subject: Re: [PATCH v5 2/2] mailbox: introduce ARM SMC based mailbox > > On Wed, Aug 28, 2019 at 03:03:02AM +0000, Peng Fan wrote: > > From: Peng Fan <peng....@nxp.com> > > > > 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://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Flore > > .kernel.org%2Fpatchwork%2Fpatch%2F812999%2F&data=02%7C01%7 > Cpeng.fa > > > n%40nxp.com%7Ca1e96c6b782d43b2cfb208d72bc05898%7C686ea1d3bc2b > 4c6fa92cd > > > 99c5c301635%7C0%7C0%7C637025977487779923&sdata=rzC%2B4Y1c > q9Y3tSDFR > > %2Fsvf5ktk7INP2rwXN%2BXdWCVjNs%3D&reserved=0 > > > > Cc: Andre Przywara <andre.przyw...@arm.com> > > Signed-off-by: Peng Fan <peng....@nxp.com> > > --- > > 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 ?
Not sure Jassi is fine with it being a required property, but I could convert it to a required property in V6. Thanks, Peng. > > -- > Regards, > Sudeep
