I checked the cable and connections. Everything looks OK. The cable is ~ 40cm long. I made these timeout changes: const unsigned long sata_deb_timing_normal[] = { 5, 1000, 20000 }; const unsigned long sata_deb_timing_hotplug[] = { 25, 5000, 20000 }; And I have these results: [ 180.907460][ T104] hardreset, Online=>Offline [ 180.912991][ T104] resume, do loop [ 181.140866][ T104] resume, after do loop [ 181.200866][ T104] debounce, SCR: 0x100 [ 181.250866][ T104] debounce, SCR: 0x101 [ 181.300866][ T104] debounce, SCR: 0x100 [ 181.360866][ T104] debounce, SCR: 0x100 [ 181.410866][ T104] debounce, SCR: 0x100 [ 181.470866][ T104] debounce, SCR: 0x100 [ 181.520866][ T104] debounce, SCR: 0x101 [ 181.580866][ T104] debounce, SCR: 0x100 [ 181.640866][ T104] debounce, SCR: 0x101 [ 181.700866][ T104] debounce, SCR: 0x100 [ 181.760865][ T104] debounce, SCR: 0x100 [ 181.810869][ T104] debounce, SCR: 0x100 [ 181.860866][ T104] debounce, SCR: 0x100 [ 181.910866][ T104] debounce, SCR: 0x101 [ 181.970866][ T104] debounce, SCR: 0x100 [ 182.020866][ T104] debounce, SCR: 0x100 [ 182.080866][ T104] debounce, SCR: 0x100 [ 182.140866][ T104] debounce, SCR: 0x100 [ 182.190866][ T104] debounce, SCR: 0x101 [ 182.250866][ T104] debounce, SCR: 0x100 [ 182.310866][ T104] debounce, SCR: 0x100 [ 182.360866][ T104] debounce, SCR: 0x100 [ 182.420866][ T104] debounce, SCR: 0x100 [ 182.480866][ T104] debounce, SCR: 0x100 [ 182.540866][ T104] debounce, SCR: 0x100 [ 182.590866][ T104] debounce, SCR: 0x100 [ 182.650866][ T104] debounce, SCR: 0x100 [ 182.710866][ T104] debounce, SCR: 0x100 [ 182.770866][ T104] debounce, SCR: 0x100 [ 182.830869][ T104] debounce, SCR: 0x101 [ 182.890866][ T104] debounce, SCR: 0x100 [ 182.950866][ T104] debounce, SCR: 0x100 [ 183.010865][ T104] debounce, SCR: 0x100 [ 183.060866][ T104] debounce, SCR: 0x100 [ 183.110870][ T104] debounce, SCR: 0x100 [ 183.170866][ T104] debounce, SCR: 0x100 [ 183.230866][ T104] debounce, SCR: 0x100 [ 183.290865][ T104] debounce, SCR: 0x100 [ 183.350869][ T104] debounce, SCR: 0x101 [ 183.400866][ T104] debounce, SCR: 0x100 [ 183.450866][ T104] debounce, SCR: 0x100 [ 183.510866][ T104] debounce, SCR: 0x101 [ 183.570866][ T104] debounce, SCR: 0x100 [ 183.630866][ T104] debounce, SCR: 0x101 [ 183.680866][ T104] debounce, SCR: 0x100 [ 183.730866][ T104] debounce, SCR: 0x100 [ 183.790866][ T104] debounce, SCR: 0x100 [ 183.840865][ T104] debounce, SCR: 0x100 [ 183.900866][ T104] debounce, SCR: 0x101 [ 183.960866][ T104] debounce, SCR: 0x100 [ 184.010866][ T104] debounce, SCR: 0x100 [ 184.060866][ T104] debounce, SCR: 0x101 [ 184.120866][ T104] debounce, SCR: 0x100 [ 184.170866][ T104] debounce, SCR: 0x100 [ 184.230866][ T104] debounce, SCR: 0x100 [ 184.280866][ T104] debounce, SCR: 0x100 [ 184.340866][ T104] debounce, SCR: 0x100 [ 184.390866][ T104] debounce, SCR: 0x0 [ 184.440866][ T104] debounce, SCR: 0x0 [ 184.490866][ T104] debounce, SCR: 0x0 [ 184.550866][ T104] debounce, SCR: 0x0 [ 184.610866][ T104] debounce, SCR: 0x100 [ 184.670866][ T104] debounce, SCR: 0x100 [ 184.720866][ T104] debounce, SCR: 0x100 [ 184.780866][ T104] debounce, SCR: 0x100 [ 184.840866][ T104] debounce, SCR: 0x100 [ 184.890868][ T104] debounce, SCR: 0x100 [ 184.940865][ T104] debounce, SCR: 0x100 [ 184.990865][ T104] debounce, SCR: 0x100 [ 185.050865][ T104] debounce, SCR: 0x100 [ 185.110866][ T104] debounce, SCR: 0x100 [ 185.160865][ T104] debounce, SCR: 0x100 [ 185.210866][ T104] debounce, SCR: 0x100 [ 185.260866][ T104] debounce, SCR: 0x100 [ 185.320866][ T104] debounce, SCR: 0x100 [ 185.380865][ T104] debounce, SCR: 0x100 [ 185.440866][ T104] debounce, SCR: 0x100 [ 185.500866][ T104] debounce, SCR: 0x101 [ 185.560866][ T104] debounce, SCR: 0x100 [ 185.620866][ T104] debounce, SCR: 0x101 [ 185.680866][ T104] debounce, SCR: 0x100 [ 185.740866][ T104] debounce, SCR: 0x101 [ 185.800866][ T104] debounce, SCR: 0x100 [ 185.860865][ T104] debounce, SCR: 0x100 [ 185.910869][ T104] debounce, SCR: 0x100 [ 185.970866][ T104] debounce, SCR: 0x100 [ 186.020866][ T104] debounce, SCR: 0x100 [ 186.070866][ T104] debounce, SCR: 0x100 [ 186.130866][ T104] debounce, SCR: 0x101 [ 186.190866][ T104] debounce, SCR: 0x100 [ 186.250866][ T104] debounce, SCR: 0x101 [ 186.310866][ T104] debounce, SCR: 0x100 [ 186.370866][ T104] debounce, SCR: 0x100 [ 186.420869][ T104] debounce, SCR: 0x101 [ 186.480866][ T104] debounce, SCR: 0x100 [ 186.530866][ T104] debounce, SCR: 0x101 [ 186.590866][ T104] debounce, SCR: 0x100 [ 186.650866][ T104] debounce, SCR: 0x101 [ 186.710866][ T104] debounce, SCR: 0x100 [ 186.760866][ T104] debounce, SCR: 0x100 [ 186.820865][ T104] debounce, SCR: 0x100 [ 186.880865][ T104] debounce, SCR: 0x100 [ 186.940868][ T104] debounce, SCR: 0x100 [ 187.000866][ T104] debounce, SCR: 0x100 [ 187.060865][ T104] debounce, SCR: 0x101 [ 187.120866][ T104] debounce, SCR: 0x100 [ 187.170866][ T104] debounce, SCR: 0x100 [ 187.230865][ T104] debounce, SCR: 0x100 [ 187.280869][ T104] debounce, SCR: 0x101 [ 187.330866][ T104] debounce, SCR: 0x101 [ 187.380866][ T104] debounce, SCR: 0x100 [ 187.440865][ T104] debounce, SCR: 0x100 [ 187.500866][ T104] debounce, SCR: 0x100 [ 187.550866][ T104] debounce, SCR: 0x100 [ 187.600866][ T104] debounce, SCR: 0x100 [ 187.660866][ T104] debounce, SCR: 0x100 [ 187.710866][ T104] debounce, SCR: 0x101 [ 187.770866][ T104] debounce, SCR: 0x100 [ 187.820866][ T104] debounce, SCR: 0x100 [ 187.880866][ T104] debounce, SCR: 0x100 [ 187.930865][ T104] debounce, SCR: 0x100 [ 187.980866][ T104] debounce, SCR: 0x101 [ 188.030866][ T104] debounce, SCR: 0x100 [ 188.090866][ T104] debounce, SCR: 0x100 [ 188.140866][ T104] debounce, SCR: 0x100 [ 188.200866][ T104] debounce, SCR: 0x100 [ 188.250866][ T104] debounce, SCR: 0x101 [ 188.310866][ T104] debounce, SCR: 0x100 [ 188.360866][ T104] debounce, SCR: 0x100 [ 188.420865][ T104] debounce, SCR: 0x100 [ 188.470869][ T104] debounce, SCR: 0x100 [ 188.530866][ T104] debounce, SCR: 0x101 [ 188.580866][ T104] debounce, SCR: 0x100 [ 188.640866][ T104] debounce, SCR: 0x100 [ 188.700866][ T104] debounce, SCR: 0x100 [ 188.750866][ T104] debounce, SCR: 0x100 [ 188.810866][ T104] debounce, SCR: 0x100 [ 188.870866][ T104] debounce, SCR: 0x100 [ 188.930866][ T104] debounce, SCR: 0x101 [ 188.980869][ T104] debounce, SCR: 0x0 [ 189.040866][ T104] debounce, SCR: 0x0 [ 189.100866][ T104] debounce, SCR: 0x0 [ 189.160866][ T104] debounce, SCR: 0x0 [ 189.220866][ T104] debounce, SCR: 0x100 [ 189.270865][ T104] debounce, SCR: 0x101 [ 189.330865][ T104] debounce, SCR: 0x100 [ 189.390866][ T104] debounce, SCR: 0x101 [ 189.450865][ T104] debounce, SCR: 0x100 [ 189.500866][ T104] debounce, SCR: 0x101 [ 189.560866][ T104] debounce, SCR: 0x100 [ 189.620866][ T104] debounce, SCR: 0x100 [ 189.680866][ T104] debounce, SCR: 0x100 [ 189.730866][ T104] debounce, SCR: 0x100 [ 189.790866][ T104] debounce, SCR: 0x100 [ 189.850866][ T104] debounce, SCR: 0x100 [ 189.910866][ T104] debounce, SCR: 0x100 [ 189.960866][ T104] debounce, SCR: 0x100 [ 190.010869][ T104] debounce, SCR: 0x100 [ 190.070866][ T104] debounce, SCR: 0x100 [ 190.130866][ T104] debounce, SCR: 0x100 [ 190.180866][ T104] debounce, SCR: 0x100 [ 190.240866][ T104] debounce, SCR: 0x100 [ 190.290866][ T104] debounce, SCR: 0x101 [ 190.350866][ T104] debounce, SCR: 0x100 [ 190.400866][ T104] debounce, SCR: 0x100 [ 190.450866][ T104] debounce, SCR: 0x100 [ 190.500865][ T104] debounce, SCR: 0x100 [ 190.550866][ T104] debounce, SCR: 0x101 [ 190.610866][ T104] debounce, SCR: 0x100 [ 190.670866][ T104] debounce, SCR: 0x100 [ 190.730866][ T104] debounce, SCR: 0x100 [ 190.790866][ T104] debounce, SCR: 0x100 [ 190.850866][ T104] debounce, SCR: 0x100 [ 190.900866][ T104] debounce, SCR: 0x100 [ 190.960865][ T104] debounce, SCR: 0x101 [ 190.964803][ T104] debounce, loop end with timeout [ 190.968740][ T104] resume, sata_link_debounce check failed [ 190.973640][ T104] hardreset, sata_link_resume check failed [ 190.984916][ T104] ata2: COMRESET failed (errno=-32) Then it repeats... Shorter timouts have mostly the same results. It never changes to anything other than 0x100, 0x101 or 0x0. When I connect the laptop HDD I get this: [ 453.239378][ T104] resume, do loop [ 453.450866][ T104] resume, after do loop [ 453.500866][ T104] debounce, SCR: 0x123 [ 453.560866][ T104] debounce, SCR: 0x123 ... same line repeats a lot ... [ 458.450866][ T104] debounce, SCR: 0x123 [ 458.510866][ T104] debounce, SCR: 0x123 [ 458.514804][ T104] resume, return at end of function [ 458.518741][ T104] hardreset, Offline=>Online [ 458.528273][ T104] hardreset, sata_pmp_supported, before check_ready [ 458.534747][ T104] [104] libata:ata_port_classify:344: ata2: found ata device by sig [ 458.720868][ T104] [104] libata:ata_port_classify:344: ata2: found ata device by sig [ 458.728734][ T104] ata2: SATA link up 3.0 Gbps (SStatus 123 SControl 300) [ 459.044097][ T104] [104] libata:ata_dev_configure:2596: ata2.00: ata_dev_configure: cfg 49:2f00 82:346b 83:7d09 84:6123 85:3469 86:bc09 87:6123 88:007f [ 459.057814][ T104] [104] libata:ata_dump_id:1363: ata2.00: 49==0x2f00 53==0x0007 63==0x0407 64==0x0003 75==0x001f [ 459.057814][ T104] 80==0x01f0 81==0x0029 82==0x346b 83==0x7d09 84==0x6123 [ 459.057814][ T104] 88==0x007f 93==0x0000 [ 459.079904][ T104] ata2.00: ATA-8: ST9500325AS, 0001SDM1, max UDMA/133 [ 459.086551][ T104] ata2.00: 976773168 sectors, multi 16: LBA48 NCQ (depth 32) [ 459.093816][ T104] [104] libata:ata_dev_set_xfermode:4305: ata2.00: set features - xfer mode [ 459.104657][ T104] [104] libata:ata_dev_configure:2596: ata2.00: ata_dev_configure: cfg 49:2f00 82:346b 83:7d09 84:6123 85:3469 86:bc09 87:6123 88:407f [ 459.118372][ T104] [104] libata:ata_dump_id:1363: ata2.00: 49==0x2f00 53==0x0007 63==0x0007 64==0x0003 75==0x001f [ 459.118372][ T104] 80==0x01f0 81==0x0029 82==0x346b 83==0x7d09 84==0x6123 [ 459.118372][ T104] 88==0x407f 93==0x0000 [ 459.140464][ T104] [104] libata:ata_dev_set_mode:3344: ata2.00: xfer_shift=12, xfer_mode=0x46 [ 459.149116][ T104] ata2.00: configured for UDMA/133 [ 459.154268][ T82] scsi 1:0:0:0: Direct-Access ATA ST9500325AS SDM1 PQ: 0 ANSI: 5 Can it be a hardware init / setup problem? In the Armada 38x Functional Specifications there is a chapter about "Amplitude and Pre-emphasize level" at the end of SATA. Marius Dinu