From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dirk Behme Subject: Re: MMC_CAP_SDIO_IRQ for omap 3430 Date: Fri, 16 Oct 2009 21:28:25 +0200 Message-ID: <4AD8C959.1000004@googlemail.com> References: <4b73d43f0910151330q6c5cae7sa2a5948b586cc215@mail.gmail.com> <4AD81DC2.4080607@googlemail.com> <42153.192.168.10.89.1255715021.squirrel@dbdmail.itg.ti.com> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <42153.192.168.10.89.1255715021.squirrel@dbdmail.itg.ti.com> Sender: linux-mmc-owner@vger.kernel.org To: Madhusudhan Chikkature Cc: linux-mmc@vger.kernel.org, John Rigby , linux-omap@vger.kernel.org, Steve Sakoman List-Id: linux-omap@vger.kernel.org Madhusudhan Chikkature wrote: > Hi Dirk, > > I am inlining the patch so that it helps review. ... > @@ -1165,8 +1178,15 @@ static void omap_hsmmc_set_ios(struct mm > break; > case MMC_BUS_WIDTH_4: > OMAP_HSMMC_WRITE(host->base, CON, con & ~DW8); > - OMAP_HSMMC_WRITE(host->base, HCTL, > - OMAP_HSMMC_READ(host->base, HCTL) | FOUR_BIT); > + if (mmc_card_sdio(host->mmc->card)) { > > I wish it could be moved to "enable_sdio_irq" so that we can avoid inclusion of > card.h and checking the type of card in the host controller driver. Yes, this would be the real clean way. But ... > But the > dependancy on 4-bit seems to be a problem here. ... most probably we have to find a workaround until (if ever?) above clean implementation is available. What we need is after SDIO mode and bus width is known, and before the first interrupt comes, to set IBG. > On the problems being discussed on testing is the interrupt source geting > cleared at the SDIO card level upon genaration of the CIRQ? If not it remains > asserted. Yes, this seems to be exactly the problem John reports in his follow up mail. Any hint how to clear SDIO interrupt? Many thanks Dirk > + OMAP_HSMMC_WRITE(host->base, HCTL, > + OMAP_HSMMC_READ(host->base, HCTL) > + | IBG | FOUR_BIT); > + } else { > + OMAP_HSMMC_WRITE(host->base, HCTL, > + OMAP_HSMMC_READ(host->base, HCTL) > + | FOUR_BIT); > + } > break; > case MMC_BUS_WIDTH_1: > OMAP_HSMMC_WRITE(host->base, CON, con & ~DW8); > @@ -1512,6 +1532,24 @@ static int omap_hsmmc_disable_fclk(struc > return 0; > } > > +static void omap_hsmmc_enable_sdio_irq(struct mmc_host *mmc, int enable) > +{ > + struct omap_hsmmc_host *host = mmc_priv(mmc); > + u32 ie, ise; > + > + ise = OMAP_HSMMC_READ(host->base, ISE); > + ie = OMAP_HSMMC_READ(host->base, IE); > + > + if (enable) { > + OMAP_HSMMC_WRITE(host->base, ISE, ise | CIRQ_ENABLE); > + OMAP_HSMMC_WRITE(host->base, IE, ie | CIRQ_ENABLE); > + } else { > + OMAP_HSMMC_WRITE(host->base, ISE, ise & ~CIRQ_ENABLE); > + OMAP_HSMMC_WRITE(host->base, IE, ie & ~CIRQ_ENABLE); > + } > + > +} > + > static const struct mmc_host_ops omap_hsmmc_ops = { > .enable = omap_hsmmc_enable_fclk, > .disable = omap_hsmmc_disable_fclk, > @@ -1519,7 +1557,7 @@ static const struct mmc_host_ops omap_hs > .set_ios = omap_hsmmc_set_ios, > .get_cd = omap_hsmmc_get_cd, > .get_ro = omap_hsmmc_get_ro, > - /* NYET -- enable_sdio_irq */ > + .enable_sdio_irq = omap_hsmmc_enable_sdio_irq, > }; > > static const struct mmc_host_ops omap_hsmmc_ps_ops = { > @@ -1529,7 +1567,7 @@ static const struct mmc_host_ops omap_hs > .set_ios = omap_hsmmc_set_ios, > .get_cd = omap_hsmmc_get_cd, > .get_ro = omap_hsmmc_get_ro, > - /* NYET -- enable_sdio_irq */ > + .enable_sdio_irq = omap_hsmmc_enable_sdio_irq, > }; > > #ifdef CONFIG_DEBUG_FS > @@ -1734,7 +1772,7 @@ static int __init omap_hsmmc_probe(struc > mmc->max_seg_size = mmc->max_req_size; > > mmc->caps |= MMC_CAP_MMC_HIGHSPEED | MMC_CAP_SD_HIGHSPEED | > - MMC_CAP_WAIT_WHILE_BUSY; > + MMC_CAP_WAIT_WHILE_BUSY | MMC_CAP_SDIO_IRQ; > > if (mmc_slot(host).wires >= 8) > mmc->caps |= MMC_CAP_8_BIT_DATA; > > > > > >> John Rigby wrote: >>> I have seen several discussions about lack of sdio irq support in the >>> hsmmc driver but no patches. Has anyone on this list implemented this >>> and/or can anyone point me to patches? >> What a coincidence ;) >> >> I'm currently working on this. See attachment what I currently have. >> It is compile tested only against recent omap linux head. I don't have >> a board using SDIO at the moment, so no real testing possible :( >> >> Some background, maybe it helps people to step in: >> >> Gumstix OMAP3 based Overo air board connects Marvell 88W8686 wifi by >> MMC port 2 in 4 bit configuration [1]. The wifi performance is quite >> bad (~100kB/s). There is some rumor that this might be SDIO irq >> related [2]. There was an attempt to fix this [3] already, but this >> doesn't work [4]. Having this, I started to look into it. >> >> I used [3], the TI Davinci driver [5] (supporting SDIO irq), the SDIO >> Simplified Specification [6] and the OMAP35x TRM [7] as starting points. >> >> Unfortunately, the Davinci MMC registers and irqs are different >> (Davinci has a dedicated SDIO irq). But combining [3] and [5] helps to >> get an idea what has to be done. >> >> I think the main issues of [3] were that it doesn't enable IBG for 4 >> bit mode ([6] chapter 8.1.2) and that mmc_omap_irq() doesn't reset the >> irq bits. >> >> Topics I still open: >> >> - Is it always necessary to deal with IE _and_ ISE register? I'm not >> totally clear what the difference between these two registers are ;) >> And in which order they have to be set. >> >> - Davinci driver [5] in line 1115 checks for data line to call >> mmc_signal_sdio_irq() for irq enable. >> >> - Davinci driver deals with SDIO in xfer_done() (line 873) >> >> - Davinci driver sets block size to 64 if SDIO in line 701 >> >> It would be quite nice if anybody likes to comment on attachment and >> help testing. >> >> Many thanks and best regards >> >> Dirk >> >> [1] http://gumstix.net/wiki/index.php?title=Overo_Wifi >> >> [2] http://groups.google.com/group/beagleboard/msg/14e822778c5eeb56 >> >> [3] http://groups.google.com/group/beagleboard/msg/d0eb69f4c20673be >> >> [4] http://groups.google.com/group/beagleboard/msg/5cdfe2a319531937 >> >> [5] >> http://arago-project.org/git/projects/?p=linux-davinci.git;a=blob;f=drivers/mmc/host/davinci_mmc.c;h=1bf0587250614c6d8abfe02028b96e0e47148ac8;hb=HEAD >> >> [6] http://www.sdcard.org/developers/tech/sdio/sd_bluetooth_spec/ >> >> [7] http://focus.ti.com/lit/ug/spruf98c/spruf98c.pdf >> >> > > >