Re: [PATCH 3/4] 44x/fsp2: tvsense workaround for dd1
From: Alistair Popple <hidden>
Date: 2017-11-27 06:24:25
Also in:
lkml
Again, I'm not familiar with this specific hardware so can only provide general comments. On Thursday, 2 November 2017 4:07:05 PM AEDT Ivan Mikhaylov wrote:
* tvsense(temperature and voltage sensors) may provide erratic sense values which may result in parity errors on CMU.
It would be good if you could provide a more detailed description of the problem (like in the comment below) and what this patch does to address it. Feel free to add my reviewed by as well. - Alistair
quoted hunk ↗ jump to hunk
Signed-off-by: Ivan Mikhaylov <redacted> --- arch/powerpc/platforms/44x/fsp2.c | 17 +++++++++++++++++ 1 files changed, 17 insertions(+), 0 deletions(-)diff --git a/arch/powerpc/platforms/44x/fsp2.c b/arch/powerpc/platforms/44x/fsp2.c index 9585725..4e12490 100644 --- a/arch/powerpc/platforms/44x/fsp2.c +++ b/arch/powerpc/platforms/44x/fsp2.c@@ -59,6 +59,23 @@ static int __init fsp2_probe(void) mtdcr(DCRN_PLB6_HD, 0xffff0000); mtdcr(DCRN_PLB6_SHD, 0xffff0000); + /* TVSENSE reset is blocked (clock gated) by the POR default of the TVS + * sleep config bit. As a consequence, TVSENSE will provide erratic + * sensor values, which may result in spurious (parity) errors + * recorded in the CMU FIR and leading to erroneous interrupt requests + * once the CMU interrupt is unmasked. + */ + + /* 1. set TVS1[UNDOZE] */ + val = mfcmu(CMUN_TVS1); + val |= 0x4; + mtcmu(CMUN_TVS1, val); + + /* 2. clear FIR[TVS] and FIR[TVSPAR] */ + val = mfcmu(CMUN_FIR0); + val |= 0x30000000; + mtcmu(CMUN_FIR0, val); + /* L2 machine checks */ mtl2(L2PLBMCKEN0, 0xffffffff); mtl2(L2PLBMCKEN1, 0x0000ffff);