Hello!

On 31.05.2020 21:07, Vladimir Oltean wrote:

From: Vladimir Oltean <vladimir.olt...@nxp.com>

Sometimes debugging a device is easiest using devmem on its register
map, and that can be seen with /proc/iomem. But some device drivers have
many memory regions. Take for example a networking switch. Its memory
map used to look like this in /proc/iomem:

1fc000000-1fc3fffff : pcie@1f0000000
   1fc000000-1fc3fffff : 0000:00:00.5
     1fc010000-1fc01ffff : sys
     1fc030000-1fc03ffff : rew
     1fc060000-1fc0603ff : s2
     1fc070000-1fc0701ff : devcpu_gcb
     1fc080000-1fc0800ff : qs
     1fc090000-1fc0900cb : ptp
     1fc100000-1fc10ffff : port0
     1fc110000-1fc11ffff : port1
     1fc120000-1fc12ffff : port2
     1fc130000-1fc13ffff : port3
     1fc140000-1fc14ffff : port4
     1fc150000-1fc15ffff : port5
     1fc200000-1fc21ffff : qsys
     1fc280000-1fc28ffff : ana

But after the patch in Fixes: was applied, the information is now
presented in a much more opaque way:

1fc000000-1fc3fffff : pcie@1f0000000
   1fc000000-1fc3fffff : 0000:00:00.5
     1fc010000-1fc01ffff : 0000:00:00.5
     1fc030000-1fc03ffff : 0000:00:00.5
     1fc060000-1fc0603ff : 0000:00:00.5
     1fc070000-1fc0701ff : 0000:00:00.5
     1fc080000-1fc0800ff : 0000:00:00.5
     1fc090000-1fc0900cb : 0000:00:00.5
     1fc100000-1fc10ffff : 0000:00:00.5
     1fc110000-1fc11ffff : 0000:00:00.5
     1fc120000-1fc12ffff : 0000:00:00.5
     1fc130000-1fc13ffff : 0000:00:00.5
     1fc140000-1fc14ffff : 0000:00:00.5
     1fc150000-1fc15ffff : 0000:00:00.5
     1fc200000-1fc21ffff : 0000:00:00.5
     1fc280000-1fc28ffff : 0000:00:00.5

That patch made a fair comment that /proc/iomem might be confusing when
it shows resources without an associated device, but we can do better
than just hide the resource name altogether. Namely, we can print the
device name _and_ the resource name. Like this:

1fc000000-1fc3fffff : pcie@1f0000000
   1fc000000-1fc3fffff : 0000:00:00.5
     1fc010000-1fc01ffff : 0000:00:00.5 sys
     1fc030000-1fc03ffff : 0000:00:00.5 rew
     1fc060000-1fc0603ff : 0000:00:00.5 s2
     1fc070000-1fc0701ff : 0000:00:00.5 devcpu_gcb
     1fc080000-1fc0800ff : 0000:00:00.5 qs
     1fc090000-1fc0900cb : 0000:00:00.5 ptp
     1fc100000-1fc10ffff : 0000:00:00.5 port0
     1fc110000-1fc11ffff : 0000:00:00.5 port1
     1fc120000-1fc12ffff : 0000:00:00.5 port2
     1fc130000-1fc13ffff : 0000:00:00.5 port3
     1fc140000-1fc14ffff : 0000:00:00.5 port4
     1fc150000-1fc15ffff : 0000:00:00.5 port5
     1fc200000-1fc21ffff : 0000:00:00.5 qsys
     1fc280000-1fc28ffff : 0000:00:00.5 ana

Fixes: 8d84b18f5678 ("devres: always use dev_name() in devm_ioremap_resource()")
Signed-off-by: Vladimir Oltean <vladimir.olt...@nxp.com>
[...]

   You didn't write the version log -- what changed since v1?

MBR, Sergei

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