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Author	SHA1	Message	Date
Stafford Horne	f5d45dc911	openrisc: Add optimized memcpy routine The generic memcpy routine provided in kernel does only byte copies. Using word copies we can lower boot time and cycles spend in memcpy quite significantly. Booting on my de0 nano I see boot times go from 7.2 to 5.6 seconds. The avg cycles in memcpy during boot go from 6467 to 1887. I tested several algorithms (see code in previous patch mails) The implementations I tested and avg cycles: - Word Copies + Loop Unrolls + Non Aligned 1882 - Word Copies + Loop Unrolls 1887 - Word Copies 2441 - Byte Copies + Loop Unrolls 6467 - Byte Copies 7600 In the end I ended up going with Word Copies + Loop Unrolls as it provides best tradeoff between simplicity and boot speedups. Signed-off-by: Stafford Horne <shorne@gmail.com>	2017-02-25 04:14:36 +09:00
Stafford Horne	266c7fad15	openrisc: Consolidate setup to use memblock instead of bootmem Clearing out one todo item. Use the memblock boot time memory which is the current standard. Tested-by: Guenter Roeck <linux@roeck-us.net> Acked-by: Jonas <jonas@southpole.se> Signed-off-by: Stafford Horne <shorne@gmail.com>	2016-12-12 23:10:00 +09:00
Jonas Bonn	616257669e	OpenRISC: Miscellaneous Adds README file, TODO list, and a couple of other pieces that didn't seem to fit into any other patch. Signed-off-by: Jonas Bonn <jonas@southpole.se> Reviewed-by: Arnd Bergmann <arnd@arndb.de>	2011-07-22 18:46:41 +02:00

Author

SHA1

Message

Date

Stafford Horne

f5d45dc911

openrisc: Add optimized memcpy routine

The generic memcpy routine provided in kernel does only byte copies.
Using word copies we can lower boot time and cycles spend in memcpy
quite significantly.

Booting on my de0 nano I see boot times go from 7.2 to 5.6 seconds.
The avg cycles in memcpy during boot go from 6467 to 1887.

I tested several algorithms (see code in previous patch mails)

The implementations I tested and avg cycles:
  - Word Copies + Loop Unrolls + Non Aligned    1882
  - Word Copies + Loop Unrolls                  1887
  - Word Copies                                 2441
  - Byte Copies + Loop Unrolls                  6467
  - Byte Copies                                 7600

In the end I ended up going with Word Copies + Loop Unrolls as it
provides best tradeoff between simplicity and boot speedups.

Signed-off-by: Stafford Horne <shorne@gmail.com>

2017-02-25 04:14:36 +09:00

Stafford Horne

266c7fad15

openrisc: Consolidate setup to use memblock instead of bootmem

Clearing out one todo item. Use the memblock boot time memory
which is the current standard.

Tested-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Jonas <jonas@southpole.se>
Signed-off-by: Stafford Horne <shorne@gmail.com>

2016-12-12 23:10:00 +09:00

Jonas Bonn

616257669e

OpenRISC: Miscellaneous

Adds README file, TODO list, and a couple of other pieces that didn't seem
to fit into any other patch.

Signed-off-by: Jonas Bonn <jonas@southpole.se>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>

2011-07-22 18:46:41 +02:00

3 Commits