Messages in this thread | | | Subject | Re: [PATCH v2 2/5] firmware: add support for ARM System Control and Power Interface(SCPI) protocol | From | "Jon Medhurst (Tixy)" <> | Date | Wed, 20 May 2015 12:17:16 +0100 |
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On Thu, 2015-05-14 at 16:42 +0100, Sudeep Holla wrote: > This patch adds support for System Control and Power Interface (SCPI) > Message Protocol used between the Application Cores(AP) and the System > Control Processor(SCP). The MHU peripheral provides a mechanism for > inter-processor communication between SCP's M3 processor and AP. > > SCP offers control and management of the core/cluster power states, > various power domain DVFS including the core/cluster, certain system > clocks configuration, thermal sensors and many others. > > This protocol driver provides interface for all the client drivers using > SCPI to make use of the features offered by the SCP. > > Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> > CC: Jassi Brar <jassisinghbrar@gmail.com> > Cc: Liviu Dudau <Liviu.Dudau@arm.com> > Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> > Cc: Jon Medhurst (Tixy) <tixy@linaro.org> > ---
Sorry for the delay in looking at this. I have one nitpick below but anyway, here's a
Reviewed-by: Jon Medhurst (Tixy) <tixy@linaro.org>
[...] > +++ b/drivers/firmware/arm_scpi.c [...] > +static void scpi_process_cmd(struct scpi_chan *ch, u32 cmd) > +{ > + unsigned long flags; > + struct scpi_xfer *t, *match = NULL; > + > + spin_lock_irqsave(&ch->rx_lock, flags); > + if (list_empty(&ch->rx_pending)) { > + spin_unlock_irqrestore(&ch->rx_lock, flags); > + return; > + } > + > + list_for_each_entry(t, &ch->rx_pending, node) > + if (CMD_XTRACT_UNIQ(t->cmd) == CMD_XTRACT_UNIQ(cmd)) { > + list_del(&t->node); > + match = t; > + break; > + } > + /* check if wait_for_completion is in progress or timed-out */ > + if (match && !completion_done(&match->done)) { > + struct scpi_shared_mem *mem = ch->rx_payload; > + int len = min(match->rx_len, CMD_SIZE(cmd)); > + > + match->status = le32_to_cpu(mem->status); > + memcpy_fromio(match->rx_buf, mem->payload, len); > + if (match->rx_len > len)
rx_len is unsigned and len is signed and so I had to go refresh my memory from the C standard before I could convince myself that this if statement was OK. Might be clearer if len was unsigned, especially as it's the 'min' of two unsigned values.
-- Tixy
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