Hi, What are the read/write kernel functions to access 64bit MMIO addresses? Are there similar functions like readl() and writel() for 64bit systems? Regards, Jagath
On Thu, 28 Feb 2013 22:46:58 +0100, Jagath Weerasinghe said:
What are the read/write kernel functions to access 64bit MMIO addresses? Are there similar functions like readl() and writel() for 64bit systems?
Are there any actual real-world cards that support 64-bit addressing but still require MMIO?
Hi, readq and writeq do the job. On Thu, Feb 28, 2013 at 11:15 PM, <Valdis.Kletnieks@vt.edu> wrote:
On Thu, 28 Feb 2013 22:46:58 +0100, Jagath Weerasinghe said:
What are the read/write kernel functions to access 64bit MMIO addresses? Are there similar functions like readl() and writel() for 64bit systems?
Are there any actual real-world cards that support 64-bit addressing but still require MMIO?
On Sun, 10 Mar 2013 20:35:37 +0100, Jagath Weerasinghe said:
readq and writeq do the job.
Please double-check how those are implemented on your architecture. I seem to remember that on some systems, readq and writeq may not be atomic and may become two bus cycles. And some hardware cares about that. It was a discussion on linux-kernel maybe a year or so ago...
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Jagath Weerasinghe -
Valdis.Kletnieks＠vt.edu