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| author | Tomas Vanek <vanekt@fbl.cz> | 2022-11-15 09:47:43 +0100 |
|---|---|---|
| committer | Tomas Vanek <vanekt@fbl.cz> | 2023-05-24 05:25:28 +0000 |
| commit | c164906420521546849d03a26977fb91838aca8e (patch) | |
| tree | 1fd15d6064ca291ca8e4825ddcdf9d3bd42e575e /doc | |
| parent | 30b0e9af8d1e68ee051ac62dd0e27c920fb396bd (diff) | |
| download | riscv-openocd-c164906420521546849d03a26977fb91838aca8e.zip riscv-openocd-c164906420521546849d03a26977fb91838aca8e.tar.gz riscv-openocd-c164906420521546849d03a26977fb91838aca8e.tar.bz2 | |
jtag/drivers/bcm2835gpio: don't touch pad setting on /dev/gpiomem
The pads were configured at a wrong memory address
if /dev/gpiomem was mapped.
The pad setting registers are not accessible in mapped /dev/gpiomem,
disable the pads setting if the driver doesn't open /dev/mem.
While on it, do not fail the driver initialization if pad mapping fails
- just emit a warning and work with unchanged pad setting.
Signed-off-by: Tomas Vanek <vanekt@fbl.cz>
Change-Id: I0bce76cade8f7efd75efd9087a7d9ba6511a6239
Reviewed-on: https://review.openocd.org/c/openocd/+/7684
Tested-by: jenkins
Reviewed-by: Jonathan Bell <jonathan@raspberrypi.com>
Reviewed-by: Antonio Borneo <borneo.antonio@gmail.com>
Diffstat (limited to 'doc')
| -rw-r--r-- | doc/openocd.texi | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/doc/openocd.texi b/doc/openocd.texi index f32ef34..f27e17c 100644 --- a/doc/openocd.texi +++ b/doc/openocd.texi @@ -3292,8 +3292,12 @@ configuration on exit. GPIO numbers >= 32 can't be used for performance reasons. GPIO configuration is handled by the generic command @ref{adapter gpio, @command{adapter gpio}}. +/dev/gpiomem is preferred for GPIO mapping with fallback to /dev/mem. +If /dev/mem is used GPIO 0-27 pads are set to the limited +slew rate and drive strength is reduced to 4 mA (2 mA on RPi 4). + See @file{interface/raspberrypi-native.cfg} for a sample config and -pinout. +@file{interface/raspberrypi-gpio-connector.cfg} for pinout. @deffn {Config Command} {bcm2835gpio speed_coeffs} @var{speed_coeff} @var{speed_offset} Set SPEED_COEFF and SPEED_OFFSET for delay calculations. If unspecified, |