[PATCH 10/12] tty: amba-pl011: add support for 32-bit register access
From: Peter Hurley <hidden>
Date: 2015-11-16 21:18:19
Also in:
linux-serial
On 11/16/2015 01:30 PM, Russell King - ARM Linux wrote:
On Mon, Nov 16, 2015 at 12:25:45PM -0600, Timur Tabi wrote:quoted
How is it touching core files? Granted, we might still need access_32b in vendor_data, but not for SBSA, since SBSA already has a mechanism to determine what 32-bit is needed or not. Then in pl011_probe(), just have: uap->port.iotype = vendor->access_32b ? UPIO_MEM32 : 0;That fails my sanity filters, sorry. iotype takes these values, and these values only: #define UPIO_PORT (SERIAL_IO_PORT) /* 8b I/O port access */#define UPIO_HUB6 (SERIAL_IO_HUB6) /* Hub6 ISA card */ #define UPIO_MEM (SERIAL_IO_MEM) /* 8b MMIO access */ #define UPIO_MEM32 (SERIAL_IO_MEM32) /* 32b little endian */ #define UPIO_AU (SERIAL_IO_AU) /* Au1x00 and RT288x type IO */ #define UPIO_TSI (SERIAL_IO_TSI) /* Tsi108/109 type IO */#define UPIO_MEM32BE (SERIAL_IO_MEM32BE) /* 32b big endian */ These are exposed to userspace, and they have meaning. We _could_ augment include/uapi/linux/serial.h and include/linux/serial_core.h to add a 16-bit LE MMIO accessor identifier, but hacking it by deciding to re-use SERIAL_IO_PORT for something it isn't is abhorrent to me.
The UPIO_* comments were added recently. The proliferation of different bitness and endianness implied that UPIO_MEM was strictly 8-bit, but that's not true and I'll remove the UPIO_MEM bitness notation from the header. The uapi header has no such notation and I think the original value and meaning of UPIO_MEM used by the pl011 driver should remain. I see no real issue with using different iotype values to describe the register access method required when other than what the driver originally used. Regards, Peter Hurley