Commit graph

9 commits

Author SHA1 Message Date
Benoît Thébaudeau 19fd7a3551 Use additive offsets
OR-ing an offset to a base address instead of adding it is dangerous
because it can only work if the base address is aligned enough for the
offset.

Moreover, if the base address or the offset has a value unknown at
compile time, then the assembly instructions dedicated to 'base +
offset' addressing on most CPUs can't be emitted by the compiler because
this would require the alignment of the base address against the offset
to be known in order to optimize 'base | offset' into 'base + offset'.
In that case, the compiler has to emit more instructions in order to
compute 'base | offset' on most CPUs, e.g. on ARM, which means larger
binary size and slower execution.

Hence, replace all occurrences of 'base | offset' with 'base + offset'.
This must become a coding rule.

Here are the results for the cc2538-demo example:
 - Compilation of uart_init():
    * before:
        REG(regs->base | UART_CC) = 0;
        200b78:	f446 637c 	orr.w	r3, r6, #4032	; 0xfc0
        200b7c:	f043 0308 	orr.w	r3, r3, #8
        200b80:	2200      	movs	r2, #0
        200b82:	601a      	str	r2, [r3, #0]

    * now:
        REG(regs->base + UART_CC) = 0;
        200b7a:	2300      	movs	r3, #0
        200b7c:	f8c4 3fc8 	str.w	r3, [r4, #4040]	; 0xfc8

 - Size of the .text section:
    * before:	0x4c7c
    * now:	0x4c28
    * saved:	84 bytes

Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau.dev@gmail.com>
2015-03-28 17:28:15 +01:00
George Oikonomou a93a8912c2 Clarify GPIO read and write macros 2015-02-16 10:17:57 +01:00
Benoît Thébaudeau 44a5c76884 cc2538: gpio: Add macros to use GPIO power-up interrupts
The GPIO power-up interrupts have to be configured and enabled in order to be
able to wake-up the SoC from PM1+ upon a signal edge occurring on a GPIO input
pin.

This set of macros allows to:
 - configure the signal edge triggering a power-up interrupt,
 - enable and disable a power-up interrupt,
 - clear a power-up interrupt flag.

Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
2013-11-26 22:10:47 +01:00
Benoît Thébaudeau 923f161b7b cc2538: gpio: Add pin read / write and interrupt clear macros
Introduce new useful GPIO macros to:
 - read the levels of some port pins,
 - write the levels of some port pins (pass bit-field value to be set),
 - clear the interrupt flags for some port pins.

These macros are cleaner and less error prone than raw register access code
copied all over the place.

Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
2013-11-15 19:48:24 +01:00
Benoît Thébaudeau 300d2d79ae cc2538: gpio: Fix usage of parameters in macros
The parameters in the GPIO macros were used without being parenthesized. This
could generate wrong values for register assignments in the case of expressions
passed as arguments to these macros.

Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
2013-11-15 19:43:06 +01:00
George Oikonomou 2957d44ff8 Merge pull request #352 from lab11/cc2538-spi-driver
Added SPI driver for CC2538
2013-09-28 13:25:17 -07:00
Brad Campbell e2af903d05 Added SPI driver for CC2538
This uses the core/dev/spi.h header and implements the spi_init()
function and the various macros for SPI operation. ssi.h contains all of
the register locations and information.

This implementation is not very versatile, mostly because I don't how to
make it flexible in the contiki system. It supports pin muxing for the
four spi pins, but other than that picks sensible defaults.

The SPI macros (like SPI_READ()) are defined in
cpu/cc2538/spi-arch.h. In order to use the SPI driver, add the following
includes to your project:

    #include "spi-arch.h
    #include "dev/spi.h"
2013-09-27 17:46:15 -04:00
Brad Campbell 982ca0fb46 Updates CC2538 GPIO
1. Fixes two of the comments to GPIO macros. They were copied but not
updated.
2. Adds SET and CLR macros for controlling GPIO pins.
2013-09-11 21:39:56 -04:00
George Oikonomou 40f49948e6 New Platform: TI CC2538 Development Kit
This commit adds cpu, platform and example files,
providing support for running Contiki on TI's cc2538 DK
2013-04-06 21:07:31 +01:00