mirror of https://gitee.com/openkylin/linux.git
7ce67a38f7
The CPSW IP implements pulse-signaled interrupts. Due to that we must write a correct, pre-defined value to the CPDMA_MACEOIVECTOR register so the controller generates a pulse on the correct IRQ line to signal the End Of Interrupt. The way the driver is written today, all four IRQ lines are requested using the same IRQ handler and, because of that, we could fall into situations where a TX IRQ fires but we tell the controller that we ended an RX IRQ (or vice-versa). This situation triggers an IRQ storm on the reserved IRQ 127 of INTC which will in turn call ack_bad_irq() which will, then, print a ton of: unexpected IRQ trap at vector 00 In order to fix the problem, we are moving all calls to cpdma_ctlr_eoi() inside the IRQ handler and making sure we *always* write the correct value to the CPDMA_MACEOIVECTOR register. Note that the algorithm assumes that IRQ numbers and value-to-be-written-to-EOI are proportional, meaning that a write of value 0 would trigger an EOI pulse for the RX_THRESHOLD Interrupt and that's the IRQ number sitting in the 0-th index of our irqs_table array. This, however, is safe at least for current implementations of CPSW so we will refrain from making the check smarter (and, as a side-effect, slower) until we actually have a platform where IRQ lines are swapped. This patch has been tested for several days with AM335x- and AM437x-based platforms. AM57x was left out because there are still pending patches to enable ethernet in mainline for that platform. A read of the TRM confirms the statement on previous paragraph. Reported-by: Yegor Yefremov <yegorslists@googlemail.com> Fixes: 510a1e7 (drivers: net: davinci_cpdma: acknowledge interrupt properly) Cc: <stable@vger.kernel.org> # v3.9+ Signed-off-by: Felipe Balbi <balbi@ti.com> Acked-by: Tony Lindgren <tony@atomide.com> Signed-off-by: David S. Miller <davem@davemloft.net> |
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| .. | ||
| Kconfig | ||
| Makefile | ||
| cpmac.c | ||
| cpsw-phy-sel.c | ||
| cpsw.c | ||
| cpsw.h | ||
| cpsw_ale.c | ||
| cpsw_ale.h | ||
| cpts.c | ||
| cpts.h | ||
| davinci_cpdma.c | ||
| davinci_cpdma.h | ||
| davinci_emac.c | ||
| davinci_mdio.c | ||
| tlan.c | ||
| tlan.h | ||