Thanks, Devkate.
To follow EDKII open forum review process, I add the patch below to see if
others have comments.
Subject: [PATCH] MdeModulePkg/NvmExpressDxe: Correct Prp list creation
algorithm.
Fix the algo of Prp list creation to calculate the number of Prp lists and the
number of entries i
Hi Feng,
This modified code does calculate PrpListNo and Remainder correctly for
both aligned and unaligned cases.
Thanks & regards,
Baban Devkate
On Thu, Apr 23, 2015 at 1:05 PM, Tian, Feng wrote:
> Hi, Devkate
>
>
>
> So the key point should be the *PrpListNo and Remainder doesn’t get
> c
Hi, Devkate
If the last entry in the first Prp list points to the last 4K data range rather
than a next Prp list, how does h/w distinguish the last entry is a pointer to
next Prp list or a valid entry to buffer?
I am consulting NVMe org and if I have some feedbacks I will get back to you.
Than
Feng, you were correct that we don't need the 2nd Prp list for such case(
case 3) and the last entry in the first Prp list points to last 4K range
rather than a pointer to next Prp List). Which is inline with NVMe spec.
*Excerpt from NVM Express 1.1, section 4.3:*
The first PRP entry contained wi
+ adding self
On Thu, Apr 9, 2015 at 3:19 PM, Baban Devkate
wrote:
> Let's take one more sample..
>
> 3) Offset = 0KB, Transfer Length = 4K * 513 blocks = 2MB + 4K
>
> Prp1 = 0K to 4KB
>
> Prp2 = pointer to a Prp List which is followed by another Prp List.
>
> The first Prp List contain
Let's take one more sample..
3) Offset = 0KB, Transfer Length = 4K * 513 blocks = 2MB + 4K
Prp1 = 0K to 4KB
Prp2 = pointer to a Prp List which is followed by another Prp List.
The first Prp List contains 511 entries to read data from offset 4KB to
offset 2MB. the last one entry is a po
Hi, Devkate
I agree the first one is a bug and need to be fixed like your proposal.
For the second one, sorry I couldn’t catch your point.
When the requested buffer size is larger than 2M, it means we need multiple PRP
list pages.
For example, when block size is 4K, memory page size is 4K
1)
PFA patch file.
On Thu, Apr 9, 2015 at 7:06 AM, Baban Devkate
wrote:
> Hi,
>
> Commit Message
>
>
> MdeModulePkg: Fixed Pointer truncation and incorrect bytes passed for PRP
> list creation.
>
> There were two issues in NvmExpressPassthru.c(
> MdeModulePkg/Bus/Pci/NvmExpressDxe/NvmE
Hi,
Commit Message
MdeModulePkg: Fixed Pointer truncation and incorrect bytes passed for PRP
list creation.
There were two issues in NvmExpressPassthru.c(
MdeModulePkg/Bus/Pci/NvmExpressDxe/NvmExpressPassthru.c)-
1.PRP list entries were zeroed out as "PrpListBase" was getting trunca
