public static ModePage_08?DecodeModePage_08(byte[] pageResponse)
{
if ((pageResponse?[0] &0x40) == 0x40)
{
return(null);
}
if ((pageResponse?[0] &0x3F) != 0x08)
{
return(null);
}
if (pageResponse[1] + 2 != pageResponse.Length)
{
return(null);
}
if (pageResponse.Length < 12)
{
return(null);
}
ModePage_08 decoded = new ModePage_08();
decoded.PS |= (pageResponse[0] & 0x80) == 0x80;
decoded.WCE |= (pageResponse[2] & 0x04) == 0x04;
decoded.MF |= (pageResponse[2] & 0x02) == 0x02;
decoded.RCD |= (pageResponse[2] & 0x01) == 0x01;
decoded.DemandReadRetentionPrio = (byte)((pageResponse[3] & 0xF0) >> 4);
decoded.WriteRetentionPriority = (byte)(pageResponse[3] & 0x0F);
decoded.DisablePreFetch = (ushort)((pageResponse[4] << 8) + pageResponse[5]);
decoded.MinimumPreFetch = (ushort)((pageResponse[6] << 8) + pageResponse[7]);
decoded.MaximumPreFetch = (ushort)((pageResponse[8] << 8) + pageResponse[9]);
decoded.MaximumPreFetchCeiling = (ushort)((pageResponse[10] << 8) + pageResponse[11]);
if (pageResponse.Length < 20)
{
return(decoded);
}
decoded.IC |= (pageResponse[2] & 0x80) == 0x80;
decoded.ABPF |= (pageResponse[2] & 0x40) == 0x40;
decoded.CAP |= (pageResponse[2] & 0x20) == 0x20;
decoded.Disc |= (pageResponse[2] & 0x10) == 0x10;
decoded.Size |= (pageResponse[2] & 0x08) == 0x08;
decoded.FSW |= (pageResponse[12] & 0x80) == 0x80;
decoded.LBCSS |= (pageResponse[12] & 0x40) == 0x40;
decoded.DRA |= (pageResponse[12] & 0x20) == 0x20;
decoded.CacheSegments = pageResponse[13];
decoded.CacheSegmentSize = (ushort)((pageResponse[14] << 8) + pageResponse[15]);
decoded.NonCacheSegmentSize = (uint)((pageResponse[17] << 16) + (pageResponse[18] << 8) + pageResponse[19]);
decoded.NV_DIS |= (pageResponse[12] & 0x01) == 0x01;
return(decoded);
}
public static string PrettifyModePage_08(ModePage_08?modePage)
{
if (!modePage.HasValue)
{
return(null);
}
ModePage_08 page = modePage.Value;
StringBuilder sb = new StringBuilder();
sb.AppendLine("SCSI Caching mode page:");
if (page.PS)
{
sb.AppendLine("\tParameters can be saved");
}
if (page.RCD)
{
sb.AppendLine("\tRead-cache is enabled");
}
if (page.WCE)
{
sb.AppendLine("\tWrite-cache is enabled");
}
switch (page.DemandReadRetentionPrio)
{
case 0:
sb.AppendLine("\tDrive does not distinguish between cached read data");
break;
case 1:
sb.AppendLine("\tData put by READ commands should be evicted from cache sooner than data put in read cache by other means");
break;
case 0xF:
sb.AppendLine("\tData put by READ commands should not be evicted if there is data cached by other means that can be evicted");
break;
default:
sb.AppendFormat("\tUnknown demand read retention priority value {0}", page.DemandReadRetentionPrio)
.AppendLine();
break;
}
switch (page.WriteRetentionPriority)
{
case 0:
sb.AppendLine("\tDrive does not distinguish between cached write data");
break;
case 1:
sb.AppendLine("\tData put by WRITE commands should be evicted from cache sooner than data put in write cache by other means");
break;
case 0xF:
sb.AppendLine("\tData put by WRITE commands should not be evicted if there is data cached by other means that can be evicted");
break;
default:
sb.AppendFormat("\tUnknown demand write retention priority value {0}", page.DemandReadRetentionPrio)
.AppendLine();
break;
}
if (page.DRA)
{
sb.AppendLine("\tRead-ahead is disabled");
}
else
{
if (page.MF)
{
sb.AppendLine("\tPre-fetch values indicate a block multiplier");
}
if (page.DisablePreFetch == 0)
{
sb.AppendLine("\tNo pre-fetch will be done");
}
else
{
sb.AppendFormat("\tPre-fetch will be done for READ commands of {0} blocks or less",
page.DisablePreFetch).AppendLine();
if (page.MinimumPreFetch > 0)
{
sb.AppendFormat("At least {0} blocks will be always pre-fetched", page.MinimumPreFetch)
.AppendLine();
}
if (page.MaximumPreFetch > 0)
{
sb.AppendFormat("\tA maximum of {0} blocks will be pre-fetched", page.MaximumPreFetch)
.AppendLine();
}
if (page.MaximumPreFetchCeiling > 0)
{
sb
.AppendFormat("\tA maximum of {0} blocks will be pre-fetched even if it is commanded to pre-fetch more",
page.MaximumPreFetchCeiling).AppendLine();
}
if (page.IC)
{
sb.AppendLine("\tDevice should use number of cache segments or cache segment size for caching");
}
if (page.ABPF)
{
sb.AppendLine("\tPre-fetch should be aborted upong receiving a new command");
}
if (page.CAP)
{
sb.AppendLine("\tCaching analysis is permitted");
}
if (page.Disc)
{
sb.AppendLine("\tPre-fetch can continue across discontinuities (such as cylinders or tracks)");
}
}
}
if (page.FSW)
{
sb.AppendLine("\tDrive should not reorder the sequence of write commands to be faster");
}
if (page.Size)
{
if (page.CacheSegmentSize > 0)
{
if (page.LBCSS)
{
sb.AppendFormat("\tDrive cache segments should be {0} blocks long", page.CacheSegmentSize)
.AppendLine();
}
else
{
sb.AppendFormat("\tDrive cache segments should be {0} bytes long", page.CacheSegmentSize)
.AppendLine();
}
}
}
else
{
if (page.CacheSegments > 0)
{
sb.AppendFormat("\tDrive should have {0} cache segments", page.CacheSegments).AppendLine();
}
}
if (page.NonCacheSegmentSize > 0)
{
sb
.AppendFormat("\tDrive shall allocate {0} bytes to buffer even when all cached data cannot be evicted",
page.NonCacheSegmentSize).AppendLine();
}
if (page.NV_DIS)
{
sb.AppendLine("\tNon-Volatile cache is disabled");
}
return(sb.ToString());
}
