Stephen Warren reported the recent commit 78506f2 (add support for
extended FIFO-size of PL011-r1p5) breaks the serial port on the
BCM2835 ARM SoC.

A UART compatible with the ARM PL011-r1p5 should have 32-deep FIFOs.
The BCM2835 UART just looks like an ARM PL011-r1p5, but has 16-deep
FIFOs just like PL011-r1p4 or earlier revisions. As a workaround for
this compatibility issue, this patch overrides the HW UART periphid
register values with the actually compatible UART periphid 0x00241011
(r1p3 or r1p4).

Reported-by: Stephen Warren <swar...@wwwdotorg.org>
Signed-off-by: Jongsung Kim <neidhard....@lge.com>
---
 arch/arm/boot/dts/bcm2835.dtsi |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/arch/arm/boot/dts/bcm2835.dtsi b/arch/arm/boot/dts/bcm2835.dtsi
index f0052dc..1e12aef 100644
--- a/arch/arm/boot/dts/bcm2835.dtsi
+++ b/arch/arm/boot/dts/bcm2835.dtsi
@@ -44,6 +44,7 @@
                        reg = <0x7e201000 0x1000>;
                        interrupts = <2 25>;
                        clock-frequency = <3000000>;
+                       arm,primecell-periphid = <0x00241011>;
                };
 
                gpio: gpio {
-- 
1.7.1

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