[PATCH] [RPI BSP] mailbox

Tue Apr 7 14:05:09 UTC 2015

On Mon, Apr 6, 2015 at 5:12 PM, QIAO YANG <yangqiao0505 at me.com> wrote:
> -----
>
> diff --git a/c/src/lib/libbsp/arm/raspberrypi/Makefile.am
> b/c/src/lib/libbsp/arm/raspberrypi/Makefile.am
> index c6133df..70bc01d 100644
> --- a/c/src/lib/libbsp/arm/raspberrypi/Makefile.am
> +++ b/c/src/lib/libbsp/arm/raspberrypi/Makefile.am
> @@ -43,6 +43,7 @@ include_bsp_HEADERS += ../shared/include/arm-release-id.h
>  include_bsp_HEADERS += include/irq.h
>  include_bsp_HEADERS += include/mmu.h
>  include_bsp_HEADERS += include/usart.h
> +include_bsp_HEADERS += include/mailbox.h
>  include_bsp_HEADERS += include/raspberrypi.h
>
>  include_libcpu_HEADERS = ../../../libcpu/arm/shared/include/cache_.h \
> @@ -123,6 +124,9 @@ libbsp_a_SOURCES += misc/timer.c
>
>  # I2C
>
> +# Mailbox
> +libbsp_a_SOURCES += misc/mailbox.c
> +
>  # Cache
>  libbsp_a_SOURCES += ../../../libcpu/shared/src/cache_manager.c
>  libbsp_a_SOURCES += ../../../libcpu/arm/shared/include/cache_.h
> diff --git a/c/src/lib/libbsp/arm/raspberrypi/include/mailbox.h
> b/c/src/lib/libbsp/arm/raspberrypi/include/mailbox.h
> new file mode 100644
> index 0000000..abdb258
> --- /dev/null
> +++ b/c/src/lib/libbsp/arm/raspberrypi/include/mailbox.h
> @@ -0,0 +1,7 @@
Need file header documentation. Please see
https://devel.rtems.org/wiki/Developer/Coding/Conventions
> +#ifndef MAILBOX_H
> +#define MAILBOX_H
> +
> +extern unsigned int readmailbox(unsigned int channel);
> +extern void writemailbox(unsigned int channel, unsigned int data);
> +
Please use function names with a "namespace". the usual convention in
RTEMS is to use Package_Class_Method like raspberrypi_mailbox_read()
and raspberrypi_mailbox_write().

> +#endif /* MAILBOX_H */
> \ No newline at end of file
> diff --git a/c/src/lib/libbsp/arm/raspberrypi/include/raspberrypi.h
> b/c/src/lib/libbsp/arm/raspberrypi/include/raspberrypi.h
> index c33e22a..e4ce18f 100644
> --- a/c/src/lib/libbsp/arm/raspberrypi/include/raspberrypi.h
> +++ b/c/src/lib/libbsp/arm/raspberrypi/include/raspberrypi.h
> @@ -208,6 +208,52 @@
>
>  /** @} */
>
> + /**
> + * @name Mailbox Registers
> + *
> + * @{
> + */
> +
> +/**
> + * NOTE:
> + */
> +#define BCM2835_MBOX_BASE (RPI_PERIPHERAL_BASE+0xB880)
> +
> +#define BCM2835_MBOX_PEEK (BCM2835_MBOX_BASE+0x10)
> +#define BCM2835_MBOX_READ (BCM2835_MBOX_BASE+0x00)
> +#define BCM2835_MBOX_WRITE (BCM2835_MBOX_BASE+0x20)
> +#define BCM2835_MBOX_STATUS (BCM2835_MBOX_BASE+0x18)
> +#define BCM2835_MBOX_SENDER (BCM2835_MBOX_BASE+0x14)
> +#define BCM2835_MBOX_CONFIG (BCM2835_MBOX_BASE+0x1C)
> +
> +/* Power Manager channel */
> +#define BCM2835_MBOX_CHANNEL_PM                0
> +/* Framebuffer channel */
> +#define BCM2835_MBOX_CHANNEL_FB                1
> + /* Virtual UART channel */
> +#define BCM2835_MBOX_CHANNEL_VUART             2
> + /* VCHIQ channel */
> +#define BCM2835_MBOX_CHANNEL_VCHIQ             3
> + /* LEDs channel */
> +#define BCM2835_MBOX_CHANNEL_LED               4
> + /* Button channel */
> +#define BCM2835_MBOX_CHANNEL_BUTTON            5
> + /* Touch screen channel */
> +#define BCM2835_MBOX_CHANNEL_TOUCHS    6
> +/* Property tags (ARM <-> Video Core) channel */
> +#define BCM2835_MBOX_CHANNEL_PROP_AVC  8
> + /* Property tags (Video Core <-> ARM) channel */
> +#define BCM2835_MBOX_CHANNEL_PROP_VCA  9
> +
> +#define BCM2835_MBOX_SUCCESS (BCM2835_MBOX_BASE+0x80000000)
> +
> +#define BCM2835_MBOX_FULL (BCM2835_MBOX_BASE+0x80000000)
> +#define BCM2835_MBOX_EMPTY (BCM2835_MBOX_BASE+0x40000000)
> +
> +
> +
> +/** @} */
> +
>
>  /** @} */
>
> diff --git a/c/src/lib/libbsp/arm/raspberrypi/misc/mailbox.c
> b/c/src/lib/libbsp/arm/raspberrypi/misc/mailbox.c
> new file mode 100644
> index 0000000..7bfb7e3
> --- /dev/null
> +++ b/c/src/lib/libbsp/arm/raspberrypi/misc/mailbox.c
> @@ -0,0 +1,22 @@
Need file header documentation
> +#include <stdint.h>
> +#include <bsp/raspberrypi.h>
> +#include <bsp/mailbox.h>
> +unsigned int readmailbox ( unsigned int channel )
> +{
> +       unsigned int data;
> +       unsigned int read_channel;
> +
> +       while ( 1 )
> +       {
> +               while ( BCM2835_REG ( BCM2835_MBOX_STATUS ) &
> BCM2835_MBOX_EMPTY );
> +               data = BCM2835_REG ( BCM2835_MBOX_READ );
> +               read_channel = ( unsigned int ) ( data & 0xF );
> +               if ( read_channel == channel )
> +                       return ( data & 0xFFFFFFF0 );
> +       }
The white spaces look wrong here. Are they tabs? Or 8 blank spaces?
Please check the style rules in the Coding Conventions page.

> +}
> +void writemailbox( unsigned int channel, unsigned int data )
> +{
> +       while ( BCM2835_REG ( BCM2835_MBOX_STATUS ) & BCM2835_MBOX_FULL );
> +       BCM2835_REG (BCM2835_MBOX_WRITE) = ( data & 0xFFFFFFF0 ) | (unsigned
> int) ( channel & 0xF );
> +}
> \ No newline at end of file
> diff --git a/c/src/lib/libbsp/arm/raspberrypi/preinstall.am
> b/c/src/lib/libbsp/arm/raspberrypi/preinstall.am
> index 70259e2..4cb7ed6 100644
> --- a/c/src/lib/libbsp/arm/raspberrypi/preinstall.am
> +++ b/c/src/lib/libbsp/arm/raspberrypi/preinstall.am
> @@ -126,6 +126,10 @@ $(PROJECT_INCLUDE)/bsp/usart.h: include/usart.h
> $(PROJECT_INCLUDE)/bsp/$(dirstam
>         $(INSTALL_DATA) $< $(PROJECT_INCLUDE)/bsp/usart.h
>  PREINSTALL_FILES += $(PROJECT_INCLUDE)/bsp/usart.h
>
> +$(PROJECT_INCLUDE)/bsp/mailbox.h: include/mailbox.h
> $(PROJECT_INCLUDE)/bsp/$(dirstamp)
> +       $(INSTALL_DATA) $< $(PROJECT_INCLUDE)/bsp/mailbox.h
> +PREINSTALL_FILES += $(PROJECT_INCLUDE)/bsp/mailbox.h
> +
>  $(PROJECT_INCLUDE)/bsp/raspberrypi.h: include/raspberrypi.h
> $(PROJECT_INCLUDE)/bsp/$(dirstamp)
>         $(INSTALL_DATA) $< $(PROJECT_INCLUDE)/bsp/raspberrypi.h
>  PREINSTALL_FILES += $(PROJECT_INCLUDE)/bsp/raspberrypi.h
>
>
> -----
>
> Here is a patch for rpi bsp which include the operation and chanel
> defininitions for mailbox and its implementations.
>
> I've only tested the framebuffer with it and it works well : set the screen
> size and get the informations.
> Andre used it for sd card reading. I've checked it out and added full
> channel definitions.
> Please point it out if further tests should be done.
>
> YANG QIAO
>
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