From mboxrd@z Thu Jan 1 00:00:00 1970 From: timur@codeaurora.org (Timur Tabi) Date: Tue, 3 Nov 2015 08:57:05 -0600 Subject: [PATCH 10/11] tty: amba-pl011: add support for 32-bit register access In-Reply-To: References: <20151103134349.GV8644@n2100.arm.linux.org.uk> Message-ID: <5638CB41.1000807@codeaurora.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Russell King wrote: > - return readw(uap->port.membase + pl011_reg_to_offset(uap, reg)); > + void __iomem *addr = uap->port.membase + pl011_reg_to_offset(uap, reg); > + > + return uap->access_32b ? readl(addr) : readw(addr); Ok, ignore my previous email. I just noticed this. This version is fine, except that it now performs a runtime check for every I/O access. Isn't that too much overhead? access_32b will always be either True or False for the life of the entire SOC. -- Sent by an employee of the Qualcomm Innovation Center, Inc. The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, hosted by The Linux Foundation.