From patchwork Mon Apr 17 09:26:18 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Rick Wertenbroek X-Patchwork-Id: 674798 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id CA3E0C77B76 for ; Mon, 17 Apr 2023 09:27:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230182AbjDQJ1A (ORCPT ); Mon, 17 Apr 2023 05:27:00 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55586 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229806AbjDQJ07 (ORCPT ); Mon, 17 Apr 2023 05:26:59 -0400 Received: from mail-ej1-x630.google.com (mail-ej1-x630.google.com [IPv6:2a00:1450:4864:20::630]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 904381FC4; Mon, 17 Apr 2023 02:26:57 -0700 (PDT) Received: by mail-ej1-x630.google.com with SMTP id xd13so28442340ejb.4; Mon, 17 Apr 2023 02:26:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20221208; t=1681723616; x=1684315616; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=GgCw//wDvbx+WHQXCgHXP4sMRKkYPpVNMBWp099ZGTU=; b=Fk2TvID3SiqSNHiNj3rAw8c+6vScwEOKKS6hLG0XrAjLUw30gELaiBLS/hky9Xoolq J1YHC1O4NT7jfgDJeudcAerVtKIeBfxddVna5R7msA9ccdrzkRkbs2lU4x83+7GGC1Vi 34myUzsYMvH/4Szqze0wvQpZ//cQhtOxzQnSewBTQ2trF8AoVhcCERAdo8cUBB9D8AY6 B24jm+UtxrTgpal3auMW9aIgfGKMt7Go7PEsfyEITwj5U0rcHKcsubKdXFVoJiPP5UVH Em2digoSzbU/LJoNw2ewbgArYvmjWwjaQAvNS1hsw3w0Yy09lGnrwVntZ6FRncjeBoXE 0JoQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1681723616; x=1684315616; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=GgCw//wDvbx+WHQXCgHXP4sMRKkYPpVNMBWp099ZGTU=; b=OZphLxV6e4iw73fGU+12xQ3nCPuyXEn5ecBIiwRRbBJamB/zYvsD33rEnn5A62Fp+G xfWPkajNrtC2tgfmF5dNsQHubHkwtT3gD0cinxQlHzJ9fC+Scsp39Imd5HUkn1Yg5bqW ZJ50gMyNk5FZi/PSvA2XZSlpfRilpn6ZslnziqJIsKT0sF18XX9shBa2IC7JVpPdhNN7 ED4042CJOkaKa37cCykE2z4gWXLhzwKYQFyjNErMA71zKvLGDtwo/5SVwYz8DaW4DUQt aCzLBP8HNBj2SpVWF3j5seKiJKXo8in7a991IauDi3ueM8iFjlJm1ogGIeXaKfaPYYuI 8PFA== X-Gm-Message-State: AAQBX9fuqDyUDh17tko3Yl7U2m/ZIxIBpUn5idebHsOCwH033ejznW27 fTt91CNWGm2iRdSJwCLPbq4= X-Google-Smtp-Source: AKy350YyFT2cN//d4D4ogxeZPO6UNqiV6weD/ibu/NLaa4eyxCr4cfcSPdLCsVXGI0y/nRjcBasRew== X-Received: by 2002:a17:906:c210:b0:94f:956:b3f7 with SMTP id d16-20020a170906c21000b0094f0956b3f7mr5725161ejz.2.1681723615728; Mon, 17 Apr 2023 02:26:55 -0700 (PDT) Received: from A13PC04R.einet.ad.eivd.ch ([193.134.219.72]) by smtp.googlemail.com with ESMTPSA id p20-20020a170906615400b0094aa087578csm6398596ejl.171.2023.04.17.02.26.54 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 17 Apr 2023 02:26:55 -0700 (PDT) From: Rick Wertenbroek To: alberto.dassatti@heig-vd.ch Cc: xxm@rock-chips.com, Rick Wertenbroek , Shawn Lin , Bjorn Helgaas , Lorenzo Pieralisi , =?utf-8?q?Krzysztof_Wilczy=C5=84?= =?utf-8?q?ski?= , Rob Herring , Krzysztof Kozlowski , Heiko Stuebner , Brian Norris , Johan Jonker , Caleb Connolly , Corentin Labbe , Judy Hsiao , Arnaud Ferraris , Hugh Cole-Baker , linux-pci@vger.kernel.org, linux-rockchip@lists.infradead.org, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: [PATCH v4 00/11] PCI: rockchip: Fix RK3399 PCIe endpoint controller driver Date: Mon, 17 Apr 2023 11:26:18 +0200 Message-Id: <20230417092631.347976-1-rick.wertenbroek@gmail.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org This is a series of patches that fixes the PCIe endpoint controller driver for the Rockchip RK3399 SoC. The driver was introduced in commit cf590b078391 ("PCI: rockchip: Add EP driver for Rockchip PCIe controller") The original driver had issues and would not allow for the RK3399 to operate in PCIe endpoint mode correctly. This patch series fixes that so that the PCIe core controller of the RK3399 SoC can now act as a PCIe endpoint. This is v4 of the patch series and addresses the comments received during the review of the v3 [1]. The changes to the v3 are minor and none of them change the logic of the driver. Thank you in advance for reviewing this patch series and hopefully getting this merged. Having a functional PCIe endpoint controller driver for the RK3399 would allow to develop further PCIe endpoint functions through the Linux PCIe endpoint framework using this SoC. [1] https://lore.kernel.org/linux-pci/20230404082426.3880812-1-rick.wertenbroek@gmail.com/ Summary of changes to V3 : * Set the fields in the standard order in the dtsi and removed unnecessary change in associated documentation, thanks to Krzysztof for pointing this out. * Added comment to explain how MSI-X capabilities advertisement was removed. * Changed Damien Le Moal address to his kernel.org address Damien Le Moal in tags. * [minor] Simplified code where a power of 2 was applied followed by a ilog2 operation. * [minor] Small code changes, replaced constant variable by macro, split remaining long lines. Summary of changes to V2 : * Fix issue with memory mapping from PCIe space to physical space There was a small mistake with the number of bits passed from the AXI physical address to the PCIe space address. * Disable the advertisement of MSI-X capabilities by the endpoint According to the technical reference manual the controller cannot generate MSI-X, so the controller should not advertise this capability. * Add the alignment value to the endpoint attributes. * [minor] Clean code (line length, variable names, small refactorings). As pointed out by reviews on the V2. * [minor] Fix error in variable name. * [minor] Remove a patch that introduced unnecessary late parameter checks. General problem statement and overview of the patch series : Problem: The Rockchip RK3399 PCIe endpoint controller driver introduced in commit cf590b078391 ("PCI: rockchip: Add EP driver for Rockchip PCIe controller") did not work. Summary of problems with the driver : * Missing dtsi entry * Could not update Device ID (DID) * The endpoint could not be configured by a host computer because the endpoint kept sending Configuration Request Retry Status (CRS) messages * The kernel would sometimes hang on probe due to access to registers in a clock domain of which the PLLs were not locked * The memory window mapping and address translation mechanism had conflicting mappings and did not follow the technical reference manual as to how the address translation should be done * Legacy IRQs were not generated by the endpoint * Message Signaled interrupts (MSI) were not generated by the endpoint * MSI-X capabilities were advertised but the controller cannot generate them according to the technical reference manual The problems have been addressed and validated through tests (see below). Summary of patches : This patch series is composed of 11 patches that do the following : 1) Remove writes to unused registers in the PCIe core register space. The registers that were written to is marked "unused" and read only in the technical reference manual of the RK3399 SoC. 2) Write PCI Device ID (DID) to correct register, the DID was written to a read only register and therefore would not update the DID. 3) Assert PCI Configuration Enable bit after probe so that it would stop sending Configuration Request Retry Status (CRS) messages to the host once configured, without this the host would retry until timeout and cancel the PCI configuration. 4) Add poll and timeout to wait for PHY PLLs to be locked, this is the only patch that also applies to the root complex function of the PCIe core controller, without this the kernel would sometimes access registers in the PHY PLL clock domain when the PLLs were not yet locked and the system would hang. This was hackily solved in other non mainline patches (e.g., in armbian) with a "msleep()" that was added after PHY PLL configuration but without realizing why it was needed. A poll with timeout seems like a sane approach. 5) Add dtsi entry for RK3399 PCIe endpoint core. The new entry is in "disabled" status by default, so unless it is explicitly enabled it will not conflict with the PCIe root complex controller entry. Developers that will enable it would know that the root complex function then must be disabled, this can be done in the board level DTS. 6) Update the RK3399 example in the documentation to a valid one. 7) Fix legacy IRQ generation for RK3399 PCIe endpoint core, the legacy IRQs were not sent by the device because their generation did not follow the instructions in the technical reference manual. They now work. 8) Fix window mapping and address translation for endpoint. The window mapping and address translation did not follow the technical reference manual and a single memory region was used which resulted in conflicting address translations for memory allocated in that region. The current patch allows to allocate up to 32 memory windows with 1MB pages. 9) Use u32 variable to access 32-bit registers, u16 variables were used to access and manipulate data of 32-bit registers, this would lead to overflows e.g., when left shifting more than 16 bits. 10) Don't advertise MSI-X in PCIe capabilities because according to the TRM the controller is not capable of generating them. 11) Set address alignment for the endpoint mode. Validation on real hardware: This patch series has been tested by me with kernels 6.0.19, 6.1.21-24, and 5.19 on real hardware, a FriendlyElec NanoPC-T4 RK3399 based single computer board connected to a host computer through PCIe x1 and x4. The driver was also tested by Damien Le Moal on a Pine Rockpro64 board [2,3]. [2] https://lore.kernel.org/linux-pci/20230330085357.2653599-1-damien.lemoal@opensource.wdc.com/ [3] https://lore.kernel.org/linux-pci/29a5ccc3-d2c8-b844-a333-28bc20657942@fastmail.com/ The PCIe endpoint test function driver was loaded on the SoC and the PCIe endpoint test driver was loaded on the host computer. The following tests were executed through this setup : * enumeration of the PCIe endpoint device (lspci) lspci -vvv * validation of PCI header and capabilities setpci and lspci -xxxx * device was recognized by host computer dans PCIe endpoint test driver was loaded lspci -v states "Kernel modules: pci_endpoint_test" * tested the BARs 0-5 sudo /usr/bin/pcitest -b 0 ... sudo /usr/bin/pcitest -b 5 * tested legacy interrupt through the test driver sudo /usr/bin/pcitest -i 0 sudo /usr/bin/pcitest -l * tested MSI interrupt through the test driver sudo /usr/bin/pcitest -i 1 sudo /usr/bin/pcitest -m 1 * tested read/write to and from host through the test driver with checksum sudo /usr/bin/pcitest -r -s 1024 sudo /usr/bin/pcitest -w -s 1024 * tested read/write with DMA enabled (all read/write tests also did IRQ) sudo /usr/bin/pcitest -r -d -s 8192 sudo /usr/bin/pcitest -w -d -s 8192 * tested larged transfers e.g., 100kB with and without DMA Commands used on the SoC to launch the endpoint function (configfs) : modprobe -i pci-epf-test mkdir -p /sys/kernel/config/pci_ep/functions/pci_epf_test/pci_epf_test.0 echo 0xb500 > /sys/kernel/config/pci_ep/functions/pci_epf_test/pci_epf_test.0/deviceid echo 0x104c > /sys/kernel/config/pci_ep/functions/pci_epf_test/pci_epf_test.0/vendorid echo 16 > /sys/kernel/config/pci_ep/functions/pci_epf_test/pci_epf_test.0/msi_interrupts ln -s /sys/kernel/config/pci_ep/functions/pci_epf_test/pci_epf_test.0 \ /sys/kernel/config/pci_ep/controllers/fd000000.pcie-ep/ echo 1 > /sys/kernel/config/pci_ep/controllers/fd000000.pcie-ep/start Note: to enable the endpoint controller on the board the file : arch/arm64/boot/dts/rockchip/rk3399-nanopc-t4.dts Was edited to set the status of &pcie0 to "disabled" and &pcie0_ep to "okay". This is not submitted as a patch because most users will use the PCIe core controller in host (root complex) mode rather than endpoint mode. I have tested and confirmed all functionality required for the endpoint with the test driver and tools. With the initial driver commit cf590b078391 ("PCI: rockchip: Add EP driver for Rockchip PCIe controller") the device would not even be enumerated by the host computer (mainly because of CRS messages being sent back to the root complex) and tests would not pass (driver would not even be loaded because DID was not set correctly) and then only the BAR test would pass. Now all tests pass as stated above. Best regards Rick Damien Le Moal (1): PCI: rockchip: Set address alignment for endpoint mode Rick Wertenbroek (10): PCI: rockchip: Remove writes to unused registers PCI: rockchip: Write PCI Device ID to correct register PCI: rockchip: Assert PCI Configuration Enable bit after probe PCI: rockchip: Add poll and timeout to wait for PHY PLLs to be locked arm64: dts: rockchip: Add dtsi entry for RK3399 PCIe endpoint core dt-bindings: PCI: Update the RK3399 example to a valid one PCI: rockchip: Fix legacy IRQ generation for RK3399 PCIe endpoint core PCI: rockchip: Fix window mapping and address translation for endpoint PCI: rockchip: Use u32 variable to access 32-bit registers PCI: rockchip: Don't advertise MSI-X in PCIe capabilities .../bindings/pci/rockchip,rk3399-pcie-ep.yaml | 4 +- arch/arm64/boot/dts/rockchip/rk3399.dtsi | 27 +++ drivers/pci/controller/pcie-rockchip-ep.c | 221 ++++++++---------- drivers/pci/controller/pcie-rockchip.c | 17 ++ drivers/pci/controller/pcie-rockchip.h | 49 ++-- 5 files changed, 181 insertions(+), 137 deletions(-)