[PATCH 10/11] tty: amba-pl011: add support for 32-bit register access

Timur Tabi timur at codeaurora.org
Tue Nov 3 06:57:05 PST 2015

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.

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