From patchwork Thu May 7 22:41:12 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Serge Semin X-Patchwork-Id: 11535041 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 85DCD1392 for ; Thu, 7 May 2020 22:41:40 +0000 (UTC) Received: by mail.kernel.org (Postfix) id 80AEA208CA; Thu, 7 May 2020 22:41:40 +0000 (UTC) Delivered-To: soc@kernel.org Received: from mail.baikalelectronics.ru (mail.baikalelectronics.com [87.245.175.226]) by mail.kernel.org (Postfix) with ESMTP id C169D20870; Thu, 7 May 2020 22:41:39 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C169D20870 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=baikalelectronics.ru Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=Sergey.Semin@baikalelectronics.ru Received: from localhost (unknown [127.0.0.1]) by mail.baikalelectronics.ru (Postfix) with ESMTP id E334480307C1; Thu, 7 May 2020 22:41:38 +0000 (UTC) X-Virus-Scanned: amavisd-new at baikalelectronics.ru Received: from mail.baikalelectronics.ru ([127.0.0.1]) by localhost (mail.baikalelectronics.ru [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id sIuzsjFm3Owd; Fri, 8 May 2020 01:41:37 +0300 (MSK) From: Serge Semin To: Thomas Bogendoerfer , Greg Kroah-Hartman , Arnd Bergmann List-Id: CC: Serge Semin , Serge Semin , Alexey Malahov , Maxim Kaurkin , Pavel Parkhomenko , Ramil Zaripov , Ekaterina Skachko , Vadim Vlasov , Alexey Kolotnikov , Paul Burton , Ralf Baechle , Tony Lindgren , Tero Kristo , Manivannan Sadhasivam , Jeffrey Hugo , Linus Walleij , Rob Herring , Olof Johansson , , , , Subject: [PATCH v2 0/4] bus: Add Baikal-T1 SoC APB/AXI bus drivers Date: Fri, 8 May 2020 01:41:12 +0300 Message-ID: <20200507224116.1523-1-Sergey.Semin@baikalelectronics.ru> In-Reply-To: <20200306130731.938808030702@mail.baikalelectronics.ru> References: <20200306130731.938808030702@mail.baikalelectronics.ru> MIME-Version: 1.0 X-ClientProxiedBy: MAIL.baikal.int (192.168.51.25) To mail (192.168.51.25) Baikal-T1 SoC CPU is based on two MIPS Warrior P5600 cores. Their main memory Non-Coherent IO interface is connected to the OCP2AXI bridge, which in turn is then connected to the DW AMBA 3 AXI Interconnect (so called Main Interconnect) with nine masters and four slaves ports. Main Interconnect is responsible for the AXI-bus traffic arbitration (QoS) and its routing from one component to another. In addition there is a Errors Handler Block (EHB) responsible to detect AXI protocol errors and device not responding situations built on top the interconnect. Baikal-T1 AXI-bus driver included in this patchset will be responsible for working with that functionality, though currently it doesn't support QoS tuning. Instead it's capable of detecting the error events, reporting an info about them to the system log, injecting artificial errors to test the driver functionality. Since AXI Interconnect doesn't provide a way to find out which devices are connected to it, so its DT node is supposed to be compatible with "simple-bus" driver, while sub-nodes shall represent the masters attached to the bus. One of the AXI Interconnect slaves is an AXI-APB bridge used to access the Baikal-T1 SoC subsystems CSRs. MMIO request from CPU and DMAC masters are routed there if they are detected to be within [0x08000000 0x1FFFFFFF] range of the physical memory. In case if an attempted APB transaction stays with no response for a pre-defined time it will be detected by the APB-bus Errors Handler Block (EHB), which will raise an interrupt, then the bus gets freed for a next operation. The APB-bus driver provides the interrupt handler to detect the erroneous address, update an errors counter and prints an error message about the faulty address. The counter and the APB-bus operations timeout can be accessed via corresponding sysfs nodes. A dedicated sysfs-node can be also used to artificially cause the bus errors described above. Since APB-bus is a platform bus, it doesn't provide a way to detect slave devices connected to it, so similarly to the AXI-bus it's also supposed to be compatible with "simple-bus" driver. This patchset is rebased and tested on the mainline Linux kernel 5.7-rc4: 0e698dfa2822 ("Linux 5.7-rc4") tag: v5.7-rc4 Note initially the driver was a part of the patchset created to reside in the kernel soc subsystem. But after a short discussion with Arnd: https://lkml.org/lkml/2020/3/6/422 we decided to move it here. New vendor prefix will be added in the framework of the next patchset: https://lkml.org/lkml/2020/5/6/1047 Changelog v2: - Assign dual GPL/BSD licenses to the bindings. - Use single lined copyright headers in the bindings. - Replace "additionalProperties: false" property with "unevaluatedProperties: false" in the bindings. - Don't use a multi-arg clock phandle reference in DT binding examples. Thus remove includes from there. - Fix some commit message and Kconfig help text spelling. - Move drivers from soc to the bus subsystem. - Convert a simple EHB drivers to the Baikal-T1 AXI and APB bus ones. - Convert APB bus driver to using regmap MMIO API. - Use syscon regmap to access the AXI-bus erroneous address. - Add reset line support. - Add Main Interconnect clock support to the AXI-bus driver. - Remove probe-status info string printout. - Discard of_match_ptr() macro utilization. - Don't print error-message if no platform IRQ found. Just return an error. - Use generic FIELD_{GET,PREP} macros instead of handwritten ones in the AXI-bus driver. Signed-off-by: Serge Semin Cc: Alexey Malahov Cc: Maxim Kaurkin Cc: Pavel Parkhomenko Cc: Ramil Zaripov Cc: Ekaterina Skachko Cc: Vadim Vlasov Cc: Alexey Kolotnikov Cc: Paul Burton Cc: Ralf Baechle Cc: Tony Lindgren Cc: Tero Kristo Cc: Manivannan Sadhasivam Cc: Jeffrey Hugo Cc: Linus Walleij Cc: Rob Herring Cc: Olof Johansson Cc: linux-mips@vger.kernel.org Cc: soc@kernel.org Cc: devicetree@vger.kernel.org Cc: linux-kernel@vger.kernel.org Serge Semin (4): dt-bindings: bus: Add Baikal-T1 AXI-bus binding dt-bindings: bus: Add Baikal-T1 APB-bus binding bus: Add Baikal-T1 AXI-bus driver bus: Add Baikal-T1 APB-bus driver .../bindings/bus/baikal,bt1-apb.yaml | 90 ++++ .../bindings/bus/baikal,bt1-axi.yaml | 95 ++++ drivers/bus/Kconfig | 30 ++ drivers/bus/Makefile | 2 + drivers/bus/bt1-apb.c | 421 ++++++++++++++++++ drivers/bus/bt1-axi.c | 318 +++++++++++++ 6 files changed, 956 insertions(+) create mode 100644 Documentation/devicetree/bindings/bus/baikal,bt1-apb.yaml create mode 100644 Documentation/devicetree/bindings/bus/baikal,bt1-axi.yaml create mode 100644 drivers/bus/bt1-apb.c create mode 100644 drivers/bus/bt1-axi.c