[RFC PATCH] ARM: dts: exynos: partial revert of Adjust bus related OPPs to the values correct for Exynos5422 Odroids

[Willy Wolff]

Hi all,

On Odroid XU3/4 board, since 5.6 with 1019fe2c728003f89ee11482cf8ec81dbd8f15ba,
the network is not working properly.

After properly booting, when trying to connect to the board via ssh, the board
hang for a while and this message happen:

[  211.111967] ------------[ cut here ]------------
[  211.117520] WARNING: CPU: 0 PID: 0 at net/sched/sch_generic.c:443 dev_watchdog+0x3ac/0x3e0
[  211.125636] NETDEV WATCHDOG: eth0 (smsc95xx): transmit queue 0 timed out
[  211.132058] Modules linked in:
[  211.134815] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.8.0-rc3-00082-gcdd3bb54332f-dirty #1
[  211.143518] Hardware name: Samsung Exynos (Flattened Device Tree)
[  211.149458] [<c0112290>] (unwind_backtrace) from [<c010d1ac>] (show_stack+0x10/0x14)
[  211.157287] [<c010d1ac>] (show_stack) from [<c051b93c>] (dump_stack+0xac/0xd8)
[  211.164416] [<c051b93c>] (dump_stack) from [<c0127a50>] (__warn+0xd0/0x108)
[  211.171301] [<c0127a50>] (__warn) from [<c0127e60>] (warn_slowpath_fmt+0x94/0xb8)
[  211.178824] [<c0127e60>] (warn_slowpath_fmt) from [<c0929b38>] (dev_watchdog+0x3ac/0x3e0)
[  211.187043] [<c0929b38>] (dev_watchdog) from [<c01c791c>] (call_timer_fn+0xd4/0x420)
[  211.194698] [<c01c791c>] (call_timer_fn) from [<c01c86ec>] (run_timer_softirq+0x620/0x784)
[  211.202980] [<c01c86ec>] (run_timer_softirq) from [<c0101408>] (__do_softirq+0x1e0/0x664)
[  211.211123] [<c0101408>] (__do_softirq) from [<c0130924>] (irq_exit+0x158/0x16c)
[  211.218467] [<c0130924>] (irq_exit) from [<c01a1ef0>] (__handle_domain_irq+0x80/0xec)
[  211.226304] [<c01a1ef0>] (__handle_domain_irq) from [<c0536eac>] (gic_handle_irq+0x58/0x9c)
[  211.234626] [<c0536eac>] (gic_handle_irq) from [<c0100af0>] (__irq_svc+0x70/0xb0)
[  211.241982] Exception stack(0xc1101f10 to 0xc1101f58)
[  211.246789] 1f00:                                     ffffffff ffffffff 00000001 0008f0bd
[  211.255230] 1f20: ffffe000 c1108eec c1108f30 00000001 00000000 c0df311c 00000000 c1076028
[  211.262303] exynos5-hsi2c 12ca0000.i2c: tx timeout
[  211.263351] 1f40: 00000000 c1101f60 c01097f8 c01097fc 600f0113 ffffffff
[  211.263649] [<c0100af0>] (__irq_svc) from [<c01097fc>] (arch_cpu_idle+0x24/0x44)
[  211.263771] [<c01097fc>] (arch_cpu_idle) from [<c01640c8>] (do_idle+0x214/0x2c0)
[  211.289414] [<c01640c8>] (do_idle) from [<c0164528>] (cpu_startup_entry+0x18/0x1c)
[  211.296999] [<c0164528>] (cpu_startup_entry) from [<c1000e54>] (start_kernel+0x4e8/0x520)
[  211.305822] irq event stamp: 585972
[  211.308637] hardirqs last  enabled at (585984): [<c0100b0c>] __irq_svc+0x8c/0xb0
[  211.316470] hardirqs last disabled at (585993): [<c019ed9c>] console_unlock+0xd4/0x654
[  211.324282] softirqs last  enabled at (585920): [<c0130640>] irq_enter_rcu+0x7c/0x84
[  211.332072] softirqs last disabled at (585921): [<c0130924>] irq_exit+0x158/0x16c
[  211.339329] ---[ end trace 5726ca773f159ae9 ]---

After that, the board continue working from serial console only, but the board
doesn't pong anymore.

Reverting some change fix the issue.

Best Regards,
Willy

Signed-off-by: Willy Wolff <willy.mh.wolff.mh@xxxxxxxxx>
---
 arch/arm/boot/dts/exynos5422-odroid-core.dtsi | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/arch/arm/boot/dts/exynos5422-odroid-core.dtsi b/arch/arm/boot/dts/exynos5422-odroid-core.dtsi
index ab27ff8bc3dc..6f7807e82035 100644
--- a/arch/arm/boot/dts/exynos5422-odroid-core.dtsi
+++ b/arch/arm/boot/dts/exynos5422-odroid-core.dtsi
@@ -81,6 +81,7 @@
 
 	bus_fsys_apb_opp_table: opp_table4 {
 		compatible = "operating-points-v2";
+		opp-shared;
 
 		/* derived from 666MHz CPLL */
 		opp00 {
@@ -412,7 +413,8 @@
 };
 
 &bus_fsys {
-	operating-points-v2 = <&bus_fsys2_opp_table>;
+	// operating-points-v2 = <&bus_fsys2_opp_table>;
+	operating-points-v2 = <&bus_fsys_apb_opp_table>;
 	devfreq = <&bus_wcore>;
 	status = "okay";
 };
-- 
2.20.1