luchianmihai/walnux
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

SAMD20: Increase FLASH waitstates to 2

Browse source
This commit is contained in:
Gregory Nutt 2014-02-18 10:37:42 -06:00
parent 7bcf29c72a
commit 1fcd2bfd10
4 changed files with 91 additions and 16 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

37
arch/arm/src/samd/sam_clockconfig.c
View file

@ -691,11 +691,40 @@ static inline void sam_dfll_reference(void)
regval |= GCLK_CLKCTRL_CLKEN;
putreg16(regval, SAM_GCLK_CLKCTRL);
/* The CLKCTRL.CLKEN bit must be synchronized to the generic clock domain.
* CLKCTRL.CLKEN will continue to read as its previous state until the
* synchronization is complete.
*/
while ((getreg16(SAM_GCLK_CLKCTRL) & GCLK_CLKCTRL_CLKEN) == 0);
}
#else
# define sam_dfll_reference()
#endif
/****************************************************************************
* Name: sam_gclck_waitsyncbusy
*
* Description:
* What until the SYNCBUSY bit is cleared. This bit is cleared when the
* synchronization of registers between the clock domains is complete.
* This bit is set when the synchronization of registers between clock
* domains is started.
*
* Input Parameters:
* None
*
* Returned Value:
* None
*
****************************************************************************/
static void sam_gclck_waitsyncbusy(void)
{
while ((getreg8(SAM_GCLK_STATUS) & GCLK_STATUS_SYNCBUSY) != 0);
}
/****************************************************************************
* Name: sam_config_gclks
*
@ -791,7 +820,7 @@ static inline void sam_gclk_config(FAR const struct sam_gclkconfig_s *config)
/* Wait for synchronization */
while ((getreg8(SAM_GCLK_STATUS) & GCLK_STATUS_SYNCBUSY) != 0);
sam_gclck_waitsyncbusy();
/* Select the generator */
@ -800,7 +829,7 @@ static inline void sam_gclk_config(FAR const struct sam_gclkconfig_s *config)
/* Wait for synchronization */
while ((getreg8(SAM_GCLK_STATUS) & GCLK_STATUS_SYNCBUSY) != 0);
sam_gclck_waitsyncbusy();
/* Write the new generator configuration */
@ -808,7 +837,7 @@ static inline void sam_gclk_config(FAR const struct sam_gclkconfig_s *config)
/* Wait for synchronization */
while ((getreg8(SAM_GCLK_STATUS) & GCLK_STATUS_SYNCBUSY) != 0);
sam_gclck_waitsyncbusy();
/* Enable the clock generator */
@ -817,7 +846,7 @@ static inline void sam_gclk_config(FAR const struct sam_gclkconfig_s *config)
/* Wait for synchronization */
while ((getreg8(SAM_GCLK_STATUS) & GCLK_STATUS_SYNCBUSY) != 0);
sam_gclck_waitsyncbusy();
}
#endif

3
configs/samd20-xplained/Kconfig
View file

@ -50,6 +50,7 @@ config SAMD20_XPLAINED_OLED1MODULE_EXT2
endchoice
endif
endmenu
if USART4_SERIAL_CONSOLE
choice
@ -78,6 +79,4 @@ config SAMD20_XPLAINED_USART4_EXT3
endchoice
endif
endmenu
endif

61
configs/samd20-xplained/README.txt
View file

@ -94,7 +94,7 @@ Modules
SPI MISO SPI MISO
----------------- ---------------------- ---------------------- ------------------------------------
18 SPI_SCK 18 PA07 SERCOM0 PAD[3] 18 PA19 SERCOM1 PAD[3]
SPI SCK SPI SCK
SPI SCK SPI SCK
----------------- ---------------------- ---------------------- ------------------------------------
19 GND 19 GND GND
----------------- ---------------------- ---------------------- ------------------------------------
@ -207,7 +207,7 @@ Modules
SPI MISO SPI MISO
----------------- ---------------------- ---------------------- ------------------------------------
18 SPI_SCK 18 PA07 SERCOM0 PAD[3] 18 PA19 SERCOM1 PAD[3]
SPI SCK SPI SCK
SPI SCK SPI SCK
----------------- ---------------------- ---------------------- ------------------------------------
19 GND 19 GND GND
----------------- ---------------------- ---------------------- ------------------------------------
@ -624,13 +624,14 @@ Configurations
SERCOM4:
System Type -> SAMD Peripheral Support
CONFIG_SAMD_SERCOM3=y
CONFIG_SAMD_SERCOM3=y : Enable one or both
CONFIG_SAMD_SERCOM4=n
Device Drivers -> Serial Driver Support -> Serial Console
CONFIG_USART3_SERIAL_CONSOLE=y
CONFIG_USART4_SERIAL_CONSOLE=y : Select only one for the console
CONFIG_USART4_SERIAL_CONSOLE=n
Device Drivers -> Serial Driver Support -> SERCOM4 Configuration
Device Drivers -> Serial Driver Support -> SERCOM3 Configuration
CONFIG_USART3_2STOP=0
CONFIG_USART3_BAUD=115200
CONFIG_USART3_BITS=8
@ -638,6 +639,19 @@ Configurations
CONFIG_USART3_RXBUFSIZE=256
CONFIG_USART3_TXBUFSIZE=256
Device Drivers -> Serial Driver Support -> SERCOM4 Configuration
CONFIG_USART4_2STOP=0
CONFIG_USART4_BAUD=115200
CONFIG_USART4_BITS=8
CONFIG_USART4_PARITY=0
CONFIG_USART4_RXBUFSIZE=256
CONFIG_USART4_TXBUFSIZE=256
Board Selection -> USART4 Connection
CONFIG_SAMD20_XPLAINED_USART4_EXT1=n : Pick on if USART4 used
CONFIG_SAMD20_XPLAINED_USART4_EXT2=n
CONFIG_SAMD20_XPLAINED_USART4_EXT3=y
3. Unless otherwise stated, the configurations are setup for
Cygwin under Windows:
@ -649,7 +663,7 @@ Configurations
that is easily reconfigured:
System Type -> Toolchain:
CONFIG_ARMV6M_TOOLCHAIN_CODESOURCERYW=y
CONFIG_ARMV6M_TOOLCHAIN_CODESOURCERYW=y
Any re-configuration should be done before making NuttX or else the
subsequent 'make' will fail. If you have already attempted building
@ -676,7 +690,17 @@ Configuration sub-directories
NOTES:
1. NOTE: If you get a compilation error like:
1. This configuration is set up to build on Windows using the Cygwin
environment using the CodeSourcery toolchain. This can be easily
changed as described above under "Configurations."
2. By default, this configuration provides a serial console on SERCOM4
via EXT3. If you would prefer to use the EDBG serial COM port or
would prefer to use SERCOM4 on EXT1 or EXT2, you will need to
reconfigure the SERCOM as described under "Configurations". See
also the section entitle "Serial Consoles" above.
3. NOTE: If you get a compilation error like:
libxx_new.cxx:74:40: error: 'operator new' takes type 'size_t'
('unsigned int') as first parameter [-fper
@ -686,7 +710,7 @@ Configuration sub-directories
an 'unsigned long int'. If this error occurs, then you may need to
toggle the value of CONFIG_CXX_NEWLONG.
2. If the I/O1 module is connected to the SAMD20 Xplained Pro, then
4. If the I/O1 module is connected to the SAMD20 Xplained Pro, then
support for the SD card slot can be enabled by making the following
changes to the configuration:
@ -750,7 +774,7 @@ Configuration sub-directories
This is a test
nsh>
3. If the OLED1 module is connected to the SAMD20 Xplained Pro, then
5. If the OLED1 module is connected to the SAMD20 Xplained Pro, then
support for the OLED display can be enabled by making the following
changes to the configuration:
@ -825,3 +849,22 @@ Configuration sub-directories
This is clearly some issue with initializing, un-initializing, and
then re-initializing. If you want to fix this, patches are quite
welcome.
STATUS/ISSUES:
1. The FLASH waistates is set to 2 (see include/board.h). According to
the data sheet, it should work at 1 but I sometimes see crashes when
the waitstates are set to one (about half of the time) (2014-2-18).
2. Garbage appears on the display sometimes after a reset (maybe 20% of
the time) or after a power cycle (less after a power cycle). I don't
understand the cause of of this but most of this can be eliminated by
simply holding the the reset button longer and releasing it cleanly
(then it fails maybe 5-10% of the time, mabe because of button
chatter?) (2014-2-18).
- The garbage is not random: It is always the same.
- This is not effected by BAUD rate. Curiously, the same garbage
appears at different BAUD settings implying that this may not even
be clock related???
- The program seems to be running normally, just producing bad output.

6
configs/samd20-xplained/include/board.h
View file

@ -348,7 +348,11 @@
* 1 48 MHz
*/
#define BOARD_FLASH_WAITSTATES 1
#if 0 /* REVISIT -- should not be necessary */
# define BOARD_FLASH_WAITSTATES 1
#else
# define BOARD_FLASH_WAITSTATES 2
#endif
/* SERCOM definitions ***************************************************************/
/* SERCOM4 is available on connectors EXT1, EXT2, and EXT3