From patchwork Thu May 18 12:29:19 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Conor Dooley X-Patchwork-Id: 13246696 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 7B49DC77B7A for ; Thu, 18 May 2023 12:35:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:Message-ID:Date:Subject:CC :To:From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References: List-Owner; bh=zg7+5Qb8HqACrjYgTIWBenUxrizTA8233CUz/9uPKY0=; b=yb+JWhNw5cQram OQiuHAFW/6KpTC48q1KW5Pvsg8kKe433Rdk1I4KOCceY6YtQL9EZ0DzhsagdNpBuJFnA0z0U6SaPa eb2st/2jvtAx/eZ8gVNOSirYQPno2+OBQBp8hIek+egluD5ibxxpo1f04zH3jinAnqyCFFXQ3vOem JgQe0hCYJWGXWsNWlHcHcjfwQp4jEr5Z+8obXDPmdRlo1iwEI+A5B9Z/ddlDivaVRT+uS7YXiF7zR Fa8Q9D1j47smE1vK9vddMT3zD1vry3CuodFpzhM6bYsbqlGzWrqI+1nOCDhkzSAy4hPEm66QpQg8k V3dlrz9WECjb9g4BgKYA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1pzcrD-00CyCi-2f; Thu, 18 May 2023 12:35:47 +0000 Received: from esa.microchip.iphmx.com ([68.232.153.233]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1pzcr9-00CyBN-2v for linux-riscv@lists.infradead.org; Thu, 18 May 2023 12:35:46 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=microchip.com; i=@microchip.com; q=dns/txt; s=mchp; t=1684413345; x=1715949345; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=aDN3dR93yq//GguZPkCXE8Ess1OefD19h7a6IUQpigk=; b=TRhHi1FTu7D/75lSYfaGS6YvMlNteEsabTM0tjD8DeW47oRTxzttAt3M BYJFN50oupONbcTn9WyKIEnwam9G7CAXgd/QPHYN9/EiNkQYZdWE6uxDo 2eG0dvMwWjxItQAWn07ZzrRrtdfkSCXltwTf1/IIyKeSrpiILw5VOk+6K 6/zUTSgu42KaN9ZJAF2a3dmgW23SR4Kvb8LYPmsnmduAzrbJcVcoUEt3V Jy/fTolQeXzVskXe11DlGbRVkhcP5YJnDpkoxgS1+IJq/PjyY6rdb2wa3 0Vg6d/U89kvxDQU8mW7SdSvhETEsDwwsKstt3EJ4Q6aG5X1lVWsWuJBRQ Q==; X-IronPort-AV: E=Sophos;i="5.99,285,1677567600"; d="scan'208";a="214432107" X-Amp-Result: SKIPPED(no attachment in message) Received: from unknown (HELO email.microchip.com) ([170.129.1.10]) by esa5.microchip.iphmx.com with ESMTP/TLS/AES256-SHA256; 18 May 2023 05:35:40 -0700 Received: from chn-vm-ex01.mchp-main.com (10.10.85.143) by chn-vm-ex03.mchp-main.com (10.10.85.151) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.21; Thu, 18 May 2023 05:35:39 -0700 Received: from wendy.microchip.com (10.10.115.15) by chn-vm-ex01.mchp-main.com (10.10.85.143) with Microsoft SMTP Server id 15.1.2507.21 via Frontend Transport; Thu, 18 May 2023 05:35:37 -0700 From: Conor Dooley To: Thierry Reding , =?utf-8?q?Uwe_Kleine-K=C3=B6n?= =?utf-8?q?ig?= CC: Daire McNamara , , , , Conor Dooley Subject: [PATCH v18 0/2] Microchip Soft IP corePWM driver Date: Thu, 18 May 2023 13:29:19 +0100 Message-ID: <20230518-reactive-nursing-23b7fe093048@wendy> X-Mailer: git-send-email 2.39.2 MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=5114; i=conor.dooley@microchip.com; h=from:subject:message-id; bh=aDN3dR93yq//GguZPkCXE8Ess1OefD19h7a6IUQpigk=; b=owGbwMvMwCFWscWwfUFT0iXG02pJDClpUvKbVv23fTP/8AcJ1bK51dzRAZfC53ms4S+YLLOVk9OW 6d7pjlIWBjEOBlkxRZbE230tUuv/uOxw7nkLM4eVCWQIAxenAEwk5TDD/4DsOS/+dmrcPSYQKt35Om /Ls6Rai3ibRw/vJt6+OOv5DC1GhtvpE5jkN7tr6H/bq/rfNJHvFa8kx72PDFwL94T3SG+O4gcA X-Developer-Key: i=conor.dooley@microchip.com; a=openpgp; fpr=F9ECA03CF54F12CD01F1655722E2C55B37CF380C X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230518_053544_130446_43C7B6DE X-CRM114-Status: GOOD ( 27.91 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org Hello, Another version, although a lot smaller of a range-diff than previously! All you get this time is the one change requested by Uwe on v17, along with a rebase on -rc1. Thanks, Conor. Changes since v17: - Explicitly cast around integer promotion on 32-bit archs - rebase on v6.4-rc1 Changes since v16: - only write out the period immediately before the duty cycle to avoid potentially racing against the period counter resetting - update some comments that had bitrotted - use Uwe's simple method for calculating period/duty & reject any period for which tmp < 255 Changes since v15: - calculate prescale modulus without using % Changes since v14: - change period_steps calculation logic to correctly handle the cases where tmp % (254 + 1) == 0, by swapping implicit truncation for explicit rounding upwards and subtracting zero - special case periods < 1/clk_rate & add a note in limitations about this, although I think this issue wasn't present prior to v15's changes - check for smaller suitable values of prescale, which picks the "more correct" value in about half of all cases, particularly those where tmp is large. - explain what I mean by the "optimal" values for prescale/period steps re-fix use of defines - add a comment about how sync_upd mode works - make the use of period_steps and prescale consistently refer to the register values rather than, in comments, using these to mean the resulting values after 1 has been added - drop the PREG_TO_VAL() macro, as most of its users are now gone & it only added to the register value versus "real" value problem - report pwmchip_add() failures Changes since v13: - couple bits of cleanup to apply_locked(), suggested by Uwe - move the overhead waiting for a change to be applied, for channels with shadow registers, to subsequent calls to apply(). This has the benefit of only waiting when two calls to apply() are close in time rather than eating the delay in every call. Changes since v11: - swap a "bare" multiply & divide for the corresponding helper to prevent overflow - factor out duplicate clk rate acquisition & period calculation - make the period calculation return void by checking the validity of the clock rate in the caller - drop the binding & dt patch, they're on-track for v6.2 via my tree Changes since v10: - reword some comments - try to assign the period if a disable is requested - drop a cast around a u8 -> u16 conversion - fix a check on period_steps that should be on the hw_ variant - split up the period calculation in get_state() to fix the result on 32 bit - add a rate variable in get_state() to only call get_rate() once - redo the locking as suggested to make it more straightforward. - stop checking for enablement in get_state() that was working around intended behaviour of the sysfs interface Changes since v9: - fixed the missing unlock that Dan reported Changes since v8: - fixed a(nother) raw 64 bit division (& built it for riscv32!) - added a check to make sure we don't try to sleep for 0 us Changes since v7: - rebased on 6.0-rc1 - reworded comments you highlighted in v7 - fixed the overkill sleeping - removed the unused variables in calc_duty - added some extra comments to explain behaviours you questioned in v7 - make the mutexes un-interruptible - fixed added the 1s you suggested for the if(period_locked) logic - added setup of the channel_enabled shadowing - fixed the period reporting for the negedge == posedge case in get_state() I had to add the enabled check, as otherwise it broke setting the period for the first time out of reset. - added a test for invalid PERIOD_STEPS values, in which case we abort if we cannot fix the period Changes from v6: - Dropped an unused variable that I'd missed - Actually check the return values of the mutex lock()s - Re-rebased on -next for the MAINTAINERS patch (again...) Changes from v5: - switched to a mutex b/c we must sleep with the lock taken - simplified the locking in apply() and added locking to get_state() - reworked apply() as requested - removed the loop in the period calculation (thanks Uwe!) - add a copy of the enable registers in the driver to save on reads. - remove the second (useless) write to sync_update - added some missing rounding in get_state() - couple other minor cleanups as requested in: https://lore.kernel.org/linux-riscv/20220709160206.cw5luo7kxdshoiua@pengutronix.de/ Changes from v4: - dropped some accidentally added files Changes before v4: https://lore.kernel.org/linux-pwm/20220721172109.941900-1-mail@conchuod.ie Conor Dooley (2): pwm: add microchip soft ip corePWM driver MAINTAINERS: add pwm to PolarFire SoC entry MAINTAINERS | 1 + drivers/pwm/Kconfig | 10 + drivers/pwm/Makefile | 1 + drivers/pwm/pwm-microchip-core.c | 507 +++++++++++++++++++++++++++++++ 4 files changed, 519 insertions(+) create mode 100644 drivers/pwm/pwm-microchip-core.c