Commit Graph

14 Commits

Author SHA1 Message Date
Bin Meng
4687919684 serial: Remove DM_FLAG_PRE_RELOC flag in various drivers
When a driver declares DM_FLAG_PRE_RELOC flag, it wishes to be
bound before relocation. However due to a bug in the DM core,
the flag only takes effect when devices are statically declared
via U_BOOT_DEVICE(). This bug has been fixed recently by commit
"dm: core: Respect drivers with the DM_FLAG_PRE_RELOC flag in
lists_bind_fdt()", but with the fix, it has a side effect that
all existing drivers that declared DM_FLAG_PRE_RELOC flag will
be bound before relocation now. This may expose potential boot
failure on some boards due to insufficient memory during the
pre-relocation stage.

To mitigate this potential impact, the following changes are
implemented:

- Remove DM_FLAG_PRE_RELOC flag in the driver, if the driver
  only supports configuration from device tree (OF_CONTROL)
- Keep DM_FLAG_PRE_RELOC flag in the driver only if the device
  is statically declared via U_BOOT_DEVICE()
- Surround DM_FLAG_PRE_RELOC flag with OF_CONTROL check, for
  drivers that support both statically declared devices and
  configuration from device tree

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
2018-11-14 09:16:28 -08:00
Tom Rini
83d290c56f SPDX: Convert all of our single license tags to Linux Kernel style
When U-Boot started using SPDX tags we were among the early adopters and
there weren't a lot of other examples to borrow from.  So we picked the
area of the file that usually had a full license text and replaced it
with an appropriate SPDX-License-Identifier: entry.  Since then, the
Linux Kernel has adopted SPDX tags and they place it as the very first
line in a file (except where shebangs are used, then it's second line)
and with slightly different comment styles than us.

In part due to community overlap, in part due to better tag visibility
and in part for other minor reasons, switch over to that style.

This commit changes all instances where we have a single declared
license in the tag as both the before and after are identical in tag
contents.  There's also a few places where I found we did not have a tag
and have introduced one.

Signed-off-by: Tom Rini <trini@konsulko.com>
2018-05-07 09:34:12 -04:00
Alexander Graf
293b9814d7 serial_bcm283x_mu: Flush RX queue after setting baud rate
After the UART was initialized, we may still have bogus data in the
RX queue if it was enabled with incorrect pin muxing before.

So let's flush the RX queue whenever we initialize baud rates.

This fixes a regression with the dynamic pinmuxing code when enable_uart=1
is not set in config.txt.

Fixes: caf2233b28 ("bcm283x: Add pinctrl driver")
Reported-by: Göran Lundberg <goran@lundberg.email>
Reported-by: Peter Robinson <pbrobinson@gmail.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
Tested-by: Peter Robinson <pbrobinson@gmail.com>
Tested-by: Tuomas Tynkkynen <tuomas@tuxera.com>
2018-03-09 12:26:47 -05:00
Alexander Graf
9dfeffe2f9 serial_bcm283x_mu: Fail loading if not muxed
The bcm283x mini-uart is only really usable as U-Boot serial output
when it is muxed to the UART pins of the RPi pin header.

So fail probing in case it is not muxed correctly, as in that case
firmware did not initialize it properly either.

Signed-off-by: Alexander Graf <agraf@suse.de>
2018-01-28 12:27:34 -05:00
Alexander Graf
bceab8d569 serial_bcm283x_mu: Always skip init
The serial initialization doesn't always quite work for me, so let's
always skip it for now. We know that firmware on the RPi initializes
us properly already.

Signed-off-by: Alexander Graf <agraf@suse.de>
2018-01-28 12:27:34 -05:00
Alexander Graf
80d5001c30 serial_bcm283x_mu: Convert to dev_read
The fdtdec API got deprecated in favor of dev_read calls.
Use those instead.

Signed-off-by: Alexander Graf <agraf@suse.de>
2018-01-28 12:27:34 -05:00
Alexander Graf
fc8523a147 serial: bcm283x_mu: Remove support for post-init disabling
We are switching to a model where a serial device doesn't even get probed when
it's not muxed properly, so we don't need device specific disabling
functionality anymore.

Signed-off-by: Alexander Graf <agraf@suse.de>
2018-01-28 12:27:33 -05:00
Simon Glass
a821c4af79 dm: Rename dev_addr..() functions
These support the flat device tree. We want to use the dev_read_..()
prefix for functions that support both flat tree and live tree. So rename
the existing functions to avoid confusion.

In the end we will have:

   1. dev_read_addr...()    - works on devices, supports flat/live tree
   2. devfdt_get_addr...()  - current functions, flat tree only
   3. of_get_address() etc. - new functions, live tree only

All drivers will be written to use 1. That function will in turn call
either 2 or 3 depending on whether the flat or live tree is in use.

Note this involves changing some dead code - the imx_lpi2c.c file.

Signed-off-by: Simon Glass <sjg@chromium.org>
2017-06-01 07:03:01 -06:00
Simon Glass
e160f7d430 dm: core: Replace of_offset with accessor
At present devices use a simple integer offset to record the device tree
node associated with the device. In preparation for supporting a live
device tree, which uses a node pointer instead, refactor existing code to
access this field through an inline function.

Signed-off-by: Simon Glass <sjg@chromium.org>
2017-02-08 06:12:14 -07:00
Fabian Vogt
cb97ad47bf serial: bcm283x_mu: support disabling after initialization
For the Raspberry Pi 3 it needs to be possible to disable the serial
device after initialization happens, as only after the GPIO device is available
it is known whether the mini uart is usable.

Signed-off-by: Fabian Vogt <fvogt@suse.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
2016-11-28 20:09:50 -05:00
Fabian Vogt
9f755f5d09 serial: bcm283x_mu: add device tree support
This patch adds device tree support for the bcm283x mini-uart driver.

Signed-off-by: Fabian Vogt <fvogt@suse.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
2016-11-28 20:09:46 -05:00
Alexander Graf
601147b06a serial: bcm283x_mu: Detect disabled serial device
On the raspberry pi, you can disable the serial port to gain dynamic frequency
scaling which can get handy at times.

However, in such a configuration the serial controller gets its rx queue filled
up with zero bytes which then happily get transmitted on to whoever calls
getc() today.

This patch adds detection logic for that case by checking whether the RX pin is
mapped to GPIO15 and disables the mini uart if it is not mapped properly.

That way we can leave the driver enabled in the tree and can determine during
runtime whether serial is usable or not, having a single binary that allows for
uart and non-uart operation.

Signed-off-by: Alexander Graf <agraf@suse.de>
Acked-by: Stephen Warren <swarren@wwwdotorg.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
2016-09-06 13:18:19 -04:00
Stephen Warren
e3a46e3ee2 serial: bcm283x_mu: make pending values more explicit
dm_serial_ops.pending should return the number of characters, not just a
valid C Boolean integer value. The existing code does already does this,
but only as an accident since BCM283X_MU_LSR_RX_READY happens to be
BIT(0). Enhance the code to be more explicit about the values it returns.

Suggested-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Stephen Warren <swarren@wwwdotorg.org>
2016-04-18 17:11:47 -04:00
Stephen Warren
3917c26909 serial: add BCM283x mini UART driver
The RPi3 typically uses the regular UART for high-speed communication with
the Bluetooth device, leaving us the mini UART to use for the serial
console. Add support for this UART so we can use it.

Signed-off-by: Stephen Warren <swarren@wwwdotorg.org>
2016-03-27 09:12:52 -04:00