From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from metis.ext.pengutronix.de ([2001:67c:670:201:290:27ff:fe1d:cc33]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1jQPpE-0002vm-Kv for barebox@lists.infradead.org; Mon, 20 Apr 2020 06:22:38 +0000 Date: Mon, 20 Apr 2020 08:22:32 +0200 From: Sascha Hauer Message-ID: <20200420062232.GB1694@pengutronix.de> References: <20200415092916.21285-1-a.fatoum@pengutronix.de> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200415092916.21285-1-a.fatoum@pengutronix.de> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "barebox" Errors-To: barebox-bounces+u.kleine-koenig=pengutronix.de@lists.infradead.org Subject: Re: [PATCH 1/4] mci: sdhci: provide sdhci_readx_poll_timeout helpers To: Ahmad Fatoum Cc: barebox@lists.infradead.org On Wed, Apr 15, 2020 at 11:29:13AM +0200, Ahmad Fatoum wrote: > The sdhci_readN accessors don't lend themselves for clean use with > readx_poll_timeout because they accept two arguments. Add > a sdhci-specific helper, so the sdhci drivers can cut down on the > timeout loop boilerplate. > > Signed-off-by: Ahmad Fatoum > --- > drivers/mci/sdhci.h | 51 +++++++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 51 insertions(+) > > diff --git a/drivers/mci/sdhci.h b/drivers/mci/sdhci.h > index a307dc97cd9a..7ac32f1541b8 100644 > --- a/drivers/mci/sdhci.h > +++ b/drivers/mci/sdhci.h > @@ -1,6 +1,8 @@ > #ifndef __MCI_SDHCI_H > #define __MCI_SDHCI_H > > +#include > + > #define SDHCI_DMA_ADDRESS 0x00 > #define SDHCI_BLOCK_SIZE__BLOCK_COUNT 0x04 > #define SDHCI_BLOCK_SIZE 0x04 > @@ -144,4 +146,53 @@ void sdhci_set_cmd_xfer_mode(struct sdhci *host, struct mci_cmd *cmd, > u32 *xfer); > int sdhci_transfer_data(struct sdhci *sdhci, struct mci_data *data); > > +/** > + * sdhci_readx_poll_timeout - Periodically poll an sdhci register until > + * a condition is met or a timeout occurs > + * @bits: access width > + * @sdhci: sdhci instance > + * @reg: Register to poll > + * @val: Variable to read the value into > + * @cond: Break condition (usually involving @val) > + * @timeout_us: Timeout in us, 0 means never timeout > + * > + * Returns 0 on success and -ETIMEDOUT upon a timeout. In either > + * case, the last read value at @reg is stored in @val. > + * > + * When available, you'll probably want to use one of the specialized > + * macros defined below rather than this macro directly. > + * > + * We do not have timing functions in the PBL, so ignore the timeout value and > + * loop infinitely here. > + * > + * Based on readx_poll_timeout from > + */ > +#define sdhci_readx_poll_timeout(bits, sdhci, reg, val, cond, timeout_us) \ > +({ \ > + uint64_t start; \ > + if (!IN_PBL && timeout_us) \ > + start = get_time_ns(); \ > + for (;;) { \ > + (val) = sdhci_read##bits(sdhci, reg); \ > + if (cond) \ > + break; \ > + if (!IN_PBL && timeout_us && \ > + is_timeout(start, ((timeout_us) * USECOND))) { \ > + (val) = sdhci_read##bits(sdhci, reg); \ > + break; \ > + } \ > + } \ > + (cond) ? 0 : -ETIMEDOUT; \ > +}) Is this really an improvement? How many variants of these helpers will we get? Sascha -- Pengutronix e.K. | | Steuerwalder Str. 21 | http://www.pengutronix.de/ | 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | _______________________________________________ barebox mailing list barebox@lists.infradead.org http://lists.infradead.org/mailman/listinfo/barebox