From: "Uwe Kleine-König" <u.kleine-koenig@pengutronix.de> To: Martin Kaiser <martin@kaiser.cx> Cc: linux-fbdev@vger.kernel.org, linux-kernel@vger.kernel.org, Sascha Hauer <kernel@pengutronix.de> Subject: Re: [PATCH] video: imxfb: correct the bitmask for DMACR_HM/_TM Date: Wed, 23 Nov 2016 10:50:52 +0100 [thread overview] Message-ID: <20161123095052.u63j26ixgc54qhkd@pengutronix.de> (raw) In-Reply-To: <20161123093113.GA10071@botnar.kaiser.cx> On Wed, Nov 23, 2016 at 10:31:13AM +0100, Martin Kaiser wrote: > Hello Uwe, all, > > Thus wrote Uwe Kleine-König (u.kleine-koenig@pengutronix.de): > > > For the MX1 which is also supported by this driver, the definitions are > > right. > > ok, understood. I wasn't able to dig up an imx1 specification. Do you > know if it's publicly available? http://www.nxp.com/assets/documents/data/en/reference-manuals/MC9328MX1RM.pdf > > So this needs a more sophisticated patch. Also I wonder why the > > register definition is in include/linux/platform_data and not in the > > driver directly. > > The DMACR_HM() and _TM() macros are meant to be used when we initialize > imx_fb_platform_data's dmacr component for a platform device. It's not > straightforward to distinguish between imx1 and imx21 at initialization > time. So you put the values to use in the device tree? Then the right thing to do is to check the device type in the driver and mask accordingly when the values are written to the hardware. > We could modify imx_fb_platform_data to use different components for > dmacr_burst, dmacr_hm, dmacr_tm and calculate the dmacr register value > in the driver where is_imx1_fb() is available. Device tree is also using > a single dmacr entry, it's probably not a good idea to do this > differently for platform devices... > > We could also define DMACR_HM_IMX1(), DMACR_HM_IMX21(), ... > > Or we could just remove the macros, they are not used by any boards in > the mainline kernel. If we don't want to break proprietary board > definitions, we could at least add a comment that the macros are > incorrect for imx21. IMHO dropping the macros is the right thing to do. Maybe even just believing the dt and write this value into the register might be acceptable. Best regards Uwe -- Pengutronix e.K. | Uwe Kleine-König | Industrial Linux Solutions | http://www.pengutronix.de/ |
WARNING: multiple messages have this Message-ID (diff)
From: "Uwe Kleine-König" <u.kleine-koenig@pengutronix.de> To: Martin Kaiser <martin@kaiser.cx> Cc: linux-fbdev@vger.kernel.org, linux-kernel@vger.kernel.org, Sascha Hauer <kernel@pengutronix.de> Subject: Re: [PATCH] video: imxfb: correct the bitmask for DMACR_HM/_TM Date: Wed, 23 Nov 2016 09:50:52 +0000 [thread overview] Message-ID: <20161123095052.u63j26ixgc54qhkd@pengutronix.de> (raw) In-Reply-To: <20161123093113.GA10071@botnar.kaiser.cx> On Wed, Nov 23, 2016 at 10:31:13AM +0100, Martin Kaiser wrote: > Hello Uwe, all, > > Thus wrote Uwe Kleine-König (u.kleine-koenig@pengutronix.de): > > > For the MX1 which is also supported by this driver, the definitions are > > right. > > ok, understood. I wasn't able to dig up an imx1 specification. Do you > know if it's publicly available? http://www.nxp.com/assets/documents/data/en/reference-manuals/MC9328MX1RM.pdf > > So this needs a more sophisticated patch. Also I wonder why the > > register definition is in include/linux/platform_data and not in the > > driver directly. > > The DMACR_HM() and _TM() macros are meant to be used when we initialize > imx_fb_platform_data's dmacr component for a platform device. It's not > straightforward to distinguish between imx1 and imx21 at initialization > time. So you put the values to use in the device tree? Then the right thing to do is to check the device type in the driver and mask accordingly when the values are written to the hardware. > We could modify imx_fb_platform_data to use different components for > dmacr_burst, dmacr_hm, dmacr_tm and calculate the dmacr register value > in the driver where is_imx1_fb() is available. Device tree is also using > a single dmacr entry, it's probably not a good idea to do this > differently for platform devices... > > We could also define DMACR_HM_IMX1(), DMACR_HM_IMX21(), ... > > Or we could just remove the macros, they are not used by any boards in > the mainline kernel. If we don't want to break proprietary board > definitions, we could at least add a comment that the macros are > incorrect for imx21. IMHO dropping the macros is the right thing to do. Maybe even just believing the dt and write this value into the register might be acceptable. Best regards Uwe -- Pengutronix e.K. | Uwe Kleine-König | Industrial Linux Solutions | http://www.pengutronix.de/ |
next prev parent reply other threads:[~2016-11-23 9:51 UTC|newest] Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top 2016-11-22 7:54 [PATCH] video: imxfb: correct the bitmask for DMACR_HM/_TM Martin Kaiser 2016-11-22 7:54 ` Martin Kaiser 2016-11-22 8:42 ` Uwe Kleine-König 2016-11-22 8:42 ` Uwe Kleine-König 2016-11-23 9:31 ` Martin Kaiser 2016-11-23 9:31 ` Martin Kaiser 2016-11-23 9:50 ` Uwe Kleine-König [this message] 2016-11-23 9:50 ` Uwe Kleine-König 2016-11-25 8:43 ` Martin Kaiser 2016-11-25 8:43 ` Martin Kaiser 2016-11-28 22:43 ` [PATCH] video: imxfb: remove the macros for initializing the DMACR Martin Kaiser 2016-11-28 22:43 ` Martin Kaiser 2016-11-29 7:49 ` Uwe Kleine-König 2016-11-29 7:49 ` Uwe Kleine-König 2016-11-29 19:50 ` [PATCH v2] " Martin Kaiser 2016-11-29 19:50 ` Martin Kaiser 2016-11-29 19:57 ` Uwe Kleine-König 2016-11-29 19:57 ` Uwe Kleine-König [not found] ` <CGME20170111124006epcas5p138afe03766a09b68eac3f93a9047ee27@epcas5p1.samsung.com> 2017-01-11 12:39 ` Bartlomiej Zolnierkiewicz 2017-01-11 12:39 ` Bartlomiej Zolnierkiewicz
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