On Xen kernels, if ATC (address translation cache) is enabled, the
first PCIe DMA read from the adapter fails with an error. This is due to
a bug ASIC, which leads to a failure of 1860 ports to be initialised.
This patch includes the fix to disable Invalidated Tag Match Enable
capability by setting the bit 26 of CHIP_MISC_PRG to 0, by default it is
set to 1.
Signed-off-by: Anil Gurumurthy <agurumur@brocade.com>
Signed-off-by: Vijaya Mohan Guvva <vmohan@brocade.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
}
}
+ /*
+ * The very first PCIe DMA Read done by LPU fails with a fatal error,
+ * when Address Translation Cache (ATC) has been enabled by system BIOS.
+ *
+ * Workaround:
+ * Disable Invalidated Tag Match Enable capability by setting the bit 26
+ * of CHIP_MISC_PRG to 0, by default it is set to 1.
+ */
+ r32 = readl(rb + CT2_CHIP_MISC_PRG);
+ writel((r32 & 0xfbffffff), (rb + CT2_CHIP_MISC_PRG));
/*
* Mask the interrupts and clear any