Re: [PATCH 2/2] x86/quark: Add Quark embedded SRAM self-test

From: Bryan O'Donoghue
Date: Wed May 06 2015 - 10:27:22 EST


On 06/05/15 03:02, Ingo Molnar wrote:

+ * This function is carefully constructed to measure and verify the
+ * performance boost provided by eSRAM. We invalidate the cache with a
+ * wbinvd() and then perform a series of reads - each of which will cause a
+ * cacheline miss. We measure the aggregate time it takes to complete the
+ * series of reads and return the delta in cycles. The calling function will
+ * pass either a pointer to DRAM or a pointer to eSRAM.
+ *
+ * @param walker: Pointer to RAM area to test.
+ * @return: Number of cycles to complete test.
+ */

<snip>


So I don't see the wbinvd() that the description mentions.

wbinvd(); isn't required to make the test do it's job. Missed scrubbing from the description - damn :(


+ * esram_self_test_init - entry point for IMR driver.
+ * esram_self_test_exit - exit point for IMR code.

Stale 'IMR' references left over from copy & paste?

Yep

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