Messages in this thread | | | Date | Wed, 23 Sep 2015 09:59:35 -0700 | From | David Daney <> | Subject | Re: [PATCH v2 2/3] of/irq: Add new function of_msi_map_rid() |
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On 09/23/2015 09:52 AM, Marc Zyngier wrote: > On Tue, 22 Sep 2015 17:00:05 -0700 > David Daney <ddaney.cavm@gmail.com> wrote: > >> From: David Daney <david.daney@cavium.com> >> >> The device tree property "msi-map" specifies how to create the PCI >> requester id used in some MSI controllers. Add a new function >> of_msi_map_rid() that finds the msi-map property and applies its >> translation to a given requester id. >> >> Signed-off-by: David Daney <david.daney@cavium.com> >> --- >> drivers/of/irq.c | 86 ++++++++++++++++++++++++++++++++++++++++++++++++++ >> include/linux/of_irq.h | 7 ++++ >> 2 files changed, 93 insertions(+) >> >> diff --git a/drivers/of/irq.c b/drivers/of/irq.c >> index 55317fa..3f64d2e 100644 >> --- a/drivers/of/irq.c >> +++ b/drivers/of/irq.c >> @@ -598,3 +598,89 @@ void of_msi_configure(struct device *dev, struct device_node *np) [...] >> + while (!matched && msi_map_len >= 4 * sizeof(__be32)) { >> + rid_base = be32_to_cpup(msi_map + 0); >> + phandle = be32_to_cpup(msi_map + 1); >> + msi_base = be32_to_cpup(msi_map + 2); >> + rid_len = be32_to_cpup(msi_map + 3); > > Rob did suggest to use of_property_read_u32_index() instead of these > be32_to_cpup(). Not sure if that'd be a major improvement though. >
I did think about that, but the micro-optimizer in me didn't feel comfortable with the overhead of rerunning of_find_property() for each value. I decided to run of_find_property() once, and then iterate through the individual values within the property.
If there are strong objections to doing it this way, we can change it.
David Daney
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