From: Benjamin Herrenschmidt <benh@kernel•crashing.org>
To: Joel Stanley <joel@jms•id.au>
Cc: dri-devel@lists•freedesktop.org, linuxppc-dev@ozlabs•org,
airlied@redhat•com, "Y . C . Chen" <yc_chen@aspeedtech•com>,
eich@suse•com
Subject: Re: [PATCH 05/12] drm/ast: Fix calculation of MCLK
Date: Fri, 24 Feb 2017 13:38:22 +1100 [thread overview]
Message-ID: <1487903902.23576.253.camel@kernel.crashing.org> (raw)
In-Reply-To: <CACPK8XdU-HZOa7vtWU3Ns1nvQG=x10DccXKMKxh_8Eqjku_7Jw@mail.gmail.com>
On Fri, 2017-02-24 at 12:54 +1030, Joel Stanley wrote:
> On Fri, Feb 24, 2017 at 9:23 AM, Benjamin Herrenschmidt
> <benh@kernel•crashing.org> wrote:
> > Some braces were missing causing an incorrect calculation.
> >
> > Y.C. Chen from Aspeed provided me with the right formula
> > which I tested on AST2400 and 2500.
>
> Y. C. Chen, can you point out this calculation in the programming
> guide?
>
> All of the PLL calculations I can find in the ast2400 documentation
> are different to this one.
Different PLL register, see my other email. I've checked the result
of the calculation on our AST2500 and AST2400 machines.
Cheers,
Ben.
> Cheers,
>
> Joel
>
> >
> > The MCLK isn't currently used by the driver (it will eventually
> > to filter modes) so the issue isn't catastrophic.
> >
> > Also make the printed value a bit more meaningful
> >
> > Signed-off-by: Benjamin Herrenschmidt <benh@kernel•crashing.org>
> > ---
> > drivers/gpu/drm/ast/ast_main.c | 6 ++++--
> > 1 file changed, 4 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/ast/ast_main.c
> > b/drivers/gpu/drm/ast/ast_main.c
> > index 718c15b..d194af3 100644
> > --- a/drivers/gpu/drm/ast/ast_main.c
> > +++ b/drivers/gpu/drm/ast/ast_main.c
> > @@ -352,7 +352,7 @@ static int ast_get_dram_info(struct drm_device
> > *dev)
> > div = 0x1;
> > break;
> > }
> > - ast->mclk = ref_pll * (num + 2) / (denum + 2) * (div *
> > 1000);
> > + ast->mclk = ref_pll * (num + 2) / ((denum + 2) * (div *
> > 1000));
> > return 0;
> > }
> >
> > @@ -496,7 +496,9 @@ int ast_driver_load(struct drm_device *dev,
> > unsigned long flags)
> > if (ret)
> > goto out_free;
> > ast->vram_size = ast_get_vram_info(dev);
> > - DRM_INFO("dram %d %d %d %08x\n", ast->mclk, ast-
> > >dram_type, ast->dram_bus_width, ast->vram_size);
> > + DRM_INFO("dram MCLK=%u Mhz type=%d bus_width=%d
> > size=%08x\n",
> > + ast->mclk, ast->dram_type,
> > + ast->dram_bus_width, ast->vram_size);
> > }
> >
> > if (need_post)
> > --
> > 2.9.3
> >
next prev parent reply other threads:[~2017-02-24 2:38 UTC|newest]
Thread overview: 39+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-02-23 22:53 [PATCH 01/12] drm/ast: Fix AST2400 POST failure without BMC FW or VBIOS Benjamin Herrenschmidt
2017-02-23 22:53 ` [PATCH 02/12] drm/ast: Handle configuration without P2A bridge Benjamin Herrenschmidt
2017-02-24 2:21 ` Joel Stanley
2017-02-24 2:26 ` Benjamin Herrenschmidt
2017-02-24 2:32 ` Benjamin Herrenschmidt
2017-02-24 2:41 ` [PATCH v5 2/12] " Benjamin Herrenschmidt
2017-02-24 2:43 ` Joel Stanley
2017-02-24 7:06 ` [PATCH 02/12] " YC Chen
2017-02-23 22:53 ` [PATCH 03/12] drm/ast: const'ify mode setting tables Benjamin Herrenschmidt
2017-02-24 2:21 ` Joel Stanley
2017-02-23 22:53 ` [PATCH 04/12] drm/ast: Remove spurrious include Benjamin Herrenschmidt
2017-02-24 2:24 ` Joel Stanley
2017-02-23 22:53 ` [PATCH 05/12] drm/ast: Fix calculation of MCLK Benjamin Herrenschmidt
2017-02-24 2:24 ` Joel Stanley
2017-02-24 2:38 ` Benjamin Herrenschmidt [this message]
2017-02-24 3:12 ` Joel Stanley
2017-02-24 7:06 ` YC Chen
2017-02-23 22:53 ` [PATCH 06/12] drm/ast: Base support for AST2500 Benjamin Herrenschmidt
2017-02-24 2:22 ` Joel Stanley
2017-02-23 22:53 ` [PATCH 07/12] drm/ast: Fixed vram size incorrect issue on POWER Benjamin Herrenschmidt
2017-02-24 2:24 ` Joel Stanley
2017-02-24 7:07 ` YC Chen
2017-02-23 22:53 ` [PATCH 08/12] drm/ast: Factor mmc_test code in POST code Benjamin Herrenschmidt
2017-02-24 2:21 ` Joel Stanley
2017-02-24 7:07 ` YC Chen
2017-02-23 22:53 ` [PATCH 09/12] drm/ast: Rename ast_init_dram_2300 to ast_post_chip_2300 Benjamin Herrenschmidt
2017-02-24 2:21 ` Joel Stanley
2017-02-24 7:08 ` YC Chen
2017-02-23 22:53 ` [PATCH 10/12] drm/ast: POST code for the new AST2500 Benjamin Herrenschmidt
2017-02-24 2:21 ` Joel Stanley
2017-02-23 22:53 ` [PATCH 11/12] drm/ast: Fix test for VGA enabled Benjamin Herrenschmidt
2017-02-23 23:24 ` Benjamin Herrenschmidt
2017-02-24 7:09 ` YC Chen
2017-02-23 22:53 ` [PATCH 12/12] drm/ast: Call open_key before enable_mmio in POST code Benjamin Herrenschmidt
2017-02-24 2:21 ` Joel Stanley
2017-02-24 7:09 ` YC Chen
2017-02-23 23:07 ` [PATCH 01/12] drm/ast: Fix AST2400 POST failure without BMC FW or VBIOS Benjamin Herrenschmidt
2017-02-24 2:23 ` Joel Stanley
2017-02-24 7:04 ` YC Chen
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1487903902.23576.253.camel@kernel.crashing.org \
--to=benh@kernel$(echo .)crashing.org \
--cc=airlied@redhat$(echo .)com \
--cc=dri-devel@lists$(echo .)freedesktop.org \
--cc=eich@suse$(echo .)com \
--cc=joel@jms$(echo .)id.au \
--cc=linuxppc-dev@ozlabs$(echo .)org \
--cc=yc_chen@aspeedtech$(echo .)com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox