kernel/linux.git/arch/arm/include/debug/zynq.S, branch v6.12.80

ARM: 9004/1: debug: Split waituart to CTS and TXRDY

2020-09-15T13:35:27+00:00

This patch was triggered by a remark from Russell that introducing a call to the waituart (needed to fix debug prints on the Qualcomm platforms) was dangerous because in some cases this will involve waiting for a modem CTS (clear to send) signal, and debug messages would maybe not work on platforms with no modem connected to the UART port: they will just hang waiting for the modem to assert CTS and this might never happen. Looking through all UART debug drivers implementing the waituart macro I discovered that all users except two actually use this macro to check if the UART is ready for TX, let's call this TXRDY. Only two debug UART drivers actually check for CTS: - arch/arm/include/debug/8250.S - arch/arm/include/debug/tegra.S The former is very significant since the 8250 is possibly the most common UART on the planet. We have the following problem: the semantics of waituart are ambiguous making it dangerous to introduce the macro to debug code fixing debug prints for Qualcomm. To start to pry this problem apart, this patch does the following: - Convert all debug UART drivers to define two macros: - waituartcts with the clear semantic to wait for CTS to be asserted - waituarttxrdy with the clear semantic to wait for the TX capability of the UART to be ready - When doing this take care to assign the right function to each drivers macro, so they now do exactly the above. - Update the three sites in the kernel invoking the waituart macro to call waituartcts/waituarttxrdy in sequence, so that the functional impact on the kernel should be zero. After this we can start to change the code sites using this code to do the right thing. Signed-off-by: Linus Walleij Signed-off-by: Russell King

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 282

2019-06-05T15:36:37+00:00

Based on 1 normalized pattern(s): this software is licensed under the terms of the gnu general public license version 2 as published by the free software foundation and may be copied distributed and modified under those terms this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 285 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Alexios Zavras Reviewed-by: Allison Randal Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190529141900.642774971@linutronix.de Signed-off-by: Greg Kroah-Hartman

ARM: zynq: Move early printk virtual address to vmalloc area

2016-02-25T13:06:03+00:00

The patch "ARM: 8432/1: move VMALLOC_END from 0xff000000 to 0xff800000" (sha1: 6ff0966052c46efb53980b8a1add2e7b49c9f560) has moved also start of VMALLOC area because size didn't change. That's why origin location of vmalloc was vmalloc : 0xf0000000 - 0xff000000 ( 240 MB) and now is vmalloc : 0xf0800000 - 0xff800000 ( 240 MB) That's why uart virtual addresses need to be changed to reflect this new memory setup. Starting address should be vmalloc start address. Signed-off-by: Michal Simek Acked-by: Arnd Bergmann

ARM: zynq: Fix earlyprintk in big endian mode

2015-07-22T07:37:58+00:00

earlyprintk messages are not appearing on the terminal emulator during a big endian kernel boot. In BE mode sending full words to UART will result in unprintable characters as they are byte swapped versions of printable ones. So send only bytes. Signed-off-by: Arun Chandran Tested-by: Michal Simek Signed-off-by: Michal Simek

ARM: zynq: Enable big-endian

2014-05-20T14:17:13+00:00

Enable ARCH_SUPPORTS_BIG_ENDIAN in Kconfig. zynq_secondary_trampoline is the first function that is called on secondary CPU. Reference: "ARM: mcpm: fix big endian issue in mcpm startup code" (sha1: 519ceb9fd10cd7e836d0aa97b2068cc9e97f463b) Fix early printk support. Based on: "ARM: pl01x debug code endian fix" (sha1: 76e3faf156fa95b6465e747d702b94faf67117fc) Signed-off-by: Michal Simek

ARM: zynq: Fix uart0 early console virtual address

2014-05-20T14:17:06+00:00

Virtual address have to have the same offset within a 2MB aligned section of virtual/phycial address space. Fix uart0 virtual address to be align with physical one. Also remove UART_SIZE which is completely unused. Reported-by: Russ Smith Signed-off-by: Michal Simek

ARM: zynq: Add waituart implementation

2014-03-17T14:12:08+00:00

Add missing waituart implementation. Signed-off-by: Michal Simek

ARM: zynq: add support for ARCH_MULTIPLATFORM

2012-11-21T09:52:13+00:00

The majority of changes are necessary to remove dependencies on header files within arch/arm/mach-zynq/include/mach: uncompress.h - Deleted. It is unused for ARCH_MULTIPLATFORM builds. uart.h: - Move uart definitions out of uart.h into debug/zynq.S, which is now the only user zynq_soc.h: - Move SCU address definitions into common.c. - Other #defines, such as PERIPHERAL_CLOCK_RATE, TTC0_BASE, etc, are unused and can be dropped Signed-off-by: Josh Cartwright Tested-by: Michal Simek

ARM: zynq: make use of debug_ll_io_init()

2012-11-21T09:52:05+00:00

Convert low-level debugging routines to make use of debug_ll_io_init(). This is part of the preparation for ARCH_MULTIPLATFORM support for Zynq. Signed-off-by: Josh Cartwright Tested-by: Michal Simek