Commit graph

10 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
Ian Martin 274b3dcd0b CC2538: Add hardware flow control (RTS/CTS) support on UART1. 2014-06-03 12:38:24 -04:00
Benoît Thébaudeau d93d129da6 cc2538: uart: Make it possible to use several UARTs simultaneously
This avoids the limitation of having a single UART available at runtime, without
duplicating code.

Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
2014-04-17 18:53:44 +02:00
Ian Martin 336224633a Eliminate UART_CONF_IBRD and UART_CONF_FBRD. 2014-03-22 10:26:03 -04:00
Ian Martin e3c19714d4 cc2538: Support any UART baudrate. 2014-03-14 16:06:24 -04:00
Benoît Thébaudeau d2f3795a30 cc2538: Clean up port and pin definitions
Homogenize port and pin definitions naming:
 - PERIPHERAL_FUNCTION_PORT for the port ID,
 - PERIPHERAL_FUNCTION_PIN for the pin ID,
 - PERIPHERAL_FUNCTION_PORT_BASE for the port base,
 - PERIPHERAL_FUNCTION_PIN_MASK for the pin mask.

Define only PERIPHERAL_FUNCTION_PORT and PERIPHERAL_FUNCTION_PIN in board.h, and
deduce PERIPHERAL_FUNCTION_PORT_BASE and PERIPHERAL_FUNCTION_PIN_MASK in the
driver from the former definitions.

Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
2013-11-25 15:00:41 +01:00
Benoît Thébaudeau b8b54a033c cc2538: uart: Fix crippled output occurring upon lpm_enter()
lpm_enter() must not enter PM1+ if the UART TX FIFO is not empty. Otherwise, the
UART clock gets disabled, and its TX is broken.

Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
2013-11-15 17:24:26 +01:00
George Oikonomou e4a454b284 Set peripheral mode for the correct UART TX/RX pins 2013-09-30 14:50:39 +01:00
George Oikonomou 6c6013b898 Make the CC2538 UART driver more configurable
* We can now very easily switch between UART0 and UART1 through a define
* We can also configure the UART RX and TX port/pin through defines
2013-08-09 12:20:25 +01:00
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