d8a4995bce
The Qualcomm Datacenter Technologies QDF2400 family of SoCs contains a custom (non-PrimeCell) implementation of the SBSA UART. Occasionally the BUSY bit in the Flag Register gets stuck as 1, erratum 44 for both 2432v1 and 2400v1 SoCs.Checking that the Transmit FIFO Empty (TXFE) bit is 0, instead of checking that the BUSY bit is 1, works around the issue. To facilitate this substitution of flags and values, introduce vendor-specific inversion of Feature Register bits when UART AMBA Port (UAP) data is available. For the earlycon case, prior to UAP availability, implement alternative putc and early_write functions. Similar to what how ARMv8 ACPI PCI quirks are detected during MCFG parsing, check the OEM fields of the Serial Port Console Redirection (SPCR) ACPI table to determine if the current platform is known to be affected by the erratum. Signed-off-by: Christopher Covington <cov@codeaurora.org> Acked-by: Russell King <rmk+kernel@armlinux.org.uk> Acked-by: Timur Tabi <timur@codeaurora.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
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| drivers | ||
| firmware | ||
| fs | ||
| include | ||
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| ipc | ||
| kernel | ||
| lib | ||
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| samples | ||
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| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
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| COPYING | ||
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| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
README
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. See Documentation/00-INDEX for a list of what is contained in each file. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.