Samsung DDR4: How read/write on mode register?
.everyoneloves__top-leaderboard:empty,.everyoneloves__mid-leaderboard:empty,.everyoneloves__bot-mid-leaderboard:empty height:90px;width:728px;box-sizing:border-box;
I have a Samsun DRAM with a K4A8G085WB-BCTD DDR4.
The device operation specification (here) says you can work with mode register through the MRS instruction [section 1.4].
I'd like to know if TRR (target row refresh) [section 2.34] is enabled or not. It says I can read the MR4 register discovering if it is active or I can write into it to activate it. However, How can I write/read the mode register practically? What kind of register is MR4?
c hardware ram cpu-registers hardware-programming
asked Nov 15 '18 at 17:18
Emanuele VannacciEmanuele Vannacci
66111
add a comment |
I have a Samsun DRAM with a K4A8G085WB-BCTD DDR4.
The device operation specification (here) says you can work with mode register through the MRS instruction [section 1.4].
I'd like to know if TRR (target row refresh) [section 2.34] is enabled or not. It says I can read the MR4 register discovering if it is active or I can write into it to activate it. However, How can I write/read the mode register practically? What kind of register is MR4?
c hardware ram cpu-registers hardware-programming
asked Nov 15 '18 at 17:18
Emanuele VannacciEmanuele Vannacci
66111
add a comment |
I have a Samsun DRAM with a K4A8G085WB-BCTD DDR4.
The device operation specification (here) says you can work with mode register through the MRS instruction [section 1.4].
I'd like to know if TRR (target row refresh) [section 2.34] is enabled or not. It says I can read the MR4 register discovering if it is active or I can write into it to activate it. However, How can I write/read the mode register practically? What kind of register is MR4?
c hardware ram cpu-registers hardware-programming
asked Nov 15 '18 at 17:18
Emanuele VannacciEmanuele Vannacci
66111
I have a Samsun DRAM with a K4A8G085WB-BCTD DDR4.
The device operation specification (here) says you can work with mode register through the MRS instruction [section 1.4].
I'd like to know if TRR (target row refresh) [section 2.34] is enabled or not. It says I can read the MR4 register discovering if it is active or I can write into it to activate it. However, How can I write/read the mode register practically? What kind of register is MR4?
c hardware ram cpu-registers hardware-programming
c hardware ram cpu-registers hardware-programming
asked Nov 15 '18 at 17:18
Emanuele VannacciEmanuele Vannacci
66111
asked Nov 15 '18 at 17:18
Emanuele VannacciEmanuele Vannacci
66111
asked Nov 15 '18 at 17:18
Emanuele VannacciEmanuele Vannacci
66111
asked Nov 15 '18 at 17:18
Emanuele VannacciEmanuele Vannacci
66111
asked Nov 15 '18 at 17:18
Emanuele VannacciEmanuele Vannacci
66111
66111
add a comment |
add a comment |
1 Answer
1
active
oldest
votes
As far as I can tell, this is not a command that would be issued from software on the host cpu to the DRAM module, but either by the DDR controller on the motherboard (or integrated with the cpu) to the DRAM module, or by a controller chip on the module to the individual DDR chips. There might be some way to get Intel's controller to pass commands through, but it's more likely that there's some Intel model-specific register (documented or undocumented, possibly exposed only through BIOS/firmware) to control the feature at a higher level.
answered Nov 15 '18 at 17:56
R..R..
158k27264567
add a comment |
Your Answer
StackExchange.ifUsing("editor", function ()
StackExchange.using("externalEditor", function ()
StackExchange.using("snippets", function ()
StackExchange.snippets.init();
);
);
, "code-snippets");
StackExchange.ready(function()
var channelOptions =
tags: "".split(" "),
id: "1"
;
initTagRenderer("".split(" "), "".split(" "), channelOptions);
StackExchange.using("externalEditor", function()
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled)
StackExchange.using("snippets", function()
createEditor();
);
else
createEditor();
);
function createEditor()
StackExchange.prepareEditor(
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: true,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: 10,
bindNavPrevention: true,
postfix: "",
imageUploader:
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
,
onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
);
);
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function ()
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f53324770%2fsamsung-ddr4-how-read-write-on-mode-register%23new-answer', 'question_page');
);
Post as a guest
Required, but never shown
1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
As far as I can tell, this is not a command that would be issued from software on the host cpu to the DRAM module, but either by the DDR controller on the motherboard (or integrated with the cpu) to the DRAM module, or by a controller chip on the module to the individual DDR chips. There might be some way to get Intel's controller to pass commands through, but it's more likely that there's some Intel model-specific register (documented or undocumented, possibly exposed only through BIOS/firmware) to control the feature at a higher level.
answered Nov 15 '18 at 17:56
R..R..
158k27264567
add a comment |
As far as I can tell, this is not a command that would be issued from software on the host cpu to the DRAM module, but either by the DDR controller on the motherboard (or integrated with the cpu) to the DRAM module, or by a controller chip on the module to the individual DDR chips. There might be some way to get Intel's controller to pass commands through, but it's more likely that there's some Intel model-specific register (documented or undocumented, possibly exposed only through BIOS/firmware) to control the feature at a higher level.
answered Nov 15 '18 at 17:56
R..R..
158k27264567
add a comment |
As far as I can tell, this is not a command that would be issued from software on the host cpu to the DRAM module, but either by the DDR controller on the motherboard (or integrated with the cpu) to the DRAM module, or by a controller chip on the module to the individual DDR chips. There might be some way to get Intel's controller to pass commands through, but it's more likely that there's some Intel model-specific register (documented or undocumented, possibly exposed only through BIOS/firmware) to control the feature at a higher level.
answered Nov 15 '18 at 17:56
R..R..
158k27264567
As far as I can tell, this is not a command that would be issued from software on the host cpu to the DRAM module, but either by the DDR controller on the motherboard (or integrated with the cpu) to the DRAM module, or by a controller chip on the module to the individual DDR chips. There might be some way to get Intel's controller to pass commands through, but it's more likely that there's some Intel model-specific register (documented or undocumented, possibly exposed only through BIOS/firmware) to control the feature at a higher level.
answered Nov 15 '18 at 17:56
R..R..
158k27264567
answered Nov 15 '18 at 17:56
R..R..
158k27264567
answered Nov 15 '18 at 17:56
R..R..
158k27264567
answered Nov 15 '18 at 17:56
R..R..
158k27264567
158k27264567
add a comment |
add a comment |
Thanks for contributing an answer to Stack Overflow!
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
To learn more, see our tips on writing great answers.
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function ()
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f53324770%2fsamsung-ddr4-how-read-write-on-mode-register%23new-answer', 'question_page');
);
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
