From patchwork Wed Jul 8 09:30:07 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kishon Vijay Abraham I X-Patchwork-Id: 11651131 X-Patchwork-Delegate: lorenzo.pieralisi@arm.com 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 70BF9913 for ; Wed, 8 Jul 2020 09:30:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 53C8D206F6 for ; Wed, 8 Jul 2020 09:30:52 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=ti.com header.i=@ti.com header.b="YbmnIA87" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728309AbgGHJar (ORCPT ); Wed, 8 Jul 2020 05:30:47 -0400 Received: from lelv0143.ext.ti.com ([198.47.23.248]:59266 "EHLO lelv0143.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726445AbgGHJaq (ORCPT ); Wed, 8 Jul 2020 05:30:46 -0400 Received: from fllv0034.itg.ti.com ([10.64.40.246]) by lelv0143.ext.ti.com (8.15.2/8.15.2) with ESMTP id 0689UZoJ102974; Wed, 8 Jul 2020 04:30:35 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1594200635; bh=fkBtp+U4H+Rsz2F0H88TEXPb+zBTcNhWs4srHjBvzA4=; h=From:To:CC:Subject:Date:In-Reply-To:References; b=YbmnIA87qijELfDMqVIVbCOxjtDpG/fQequvcUHj0zHThJDnSfmoq6+KHm0CfSHV6 cEgDuezF9cJ/NH6feu3tZfgclP35eG9ixUb3vjMKt4izyS4G2L6pZ8sLzxIbCUTews DAnxGeLIjoHn0RRg8f28UaDXpS/zENQx16naTmOI= Received: from DFLE103.ent.ti.com (dfle103.ent.ti.com [10.64.6.24]) by fllv0034.itg.ti.com (8.15.2/8.15.2) with ESMTPS id 0689UYYe043534 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=FAIL); Wed, 8 Jul 2020 04:30:35 -0500 Received: from DFLE106.ent.ti.com (10.64.6.27) by DFLE103.ent.ti.com (10.64.6.24) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1979.3; Wed, 8 Jul 2020 04:30:34 -0500 Received: from fllv0040.itg.ti.com (10.64.41.20) by DFLE106.ent.ti.com (10.64.6.27) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1979.3 via Frontend Transport; Wed, 8 Jul 2020 04:30:34 -0500 Received: from a0393678ub.india.ti.com (ileax41-snat.itg.ti.com [10.172.224.153]) by fllv0040.itg.ti.com (8.15.2/8.15.2) with ESMTP id 0689UJEK098512; Wed, 8 Jul 2020 04:30:31 -0500 From: Kishon Vijay Abraham I To: Tom Joseph , Bjorn Helgaas , Rob Herring , Kishon Vijay Abraham I , Lorenzo Pieralisi , Arnd Bergmann CC: Greg Kroah-Hartman , , , , , Subject: [PATCH v6 03/14] PCI: cadence: Convert all r/w accessors to perform only 32-bit accesses Date: Wed, 8 Jul 2020 15:00:07 +0530 Message-ID: <20200708093018.28474-4-kishon@ti.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200708093018.28474-1-kishon@ti.com> References: <20200708093018.28474-1-kishon@ti.com> MIME-Version: 1.0 X-EXCLAIMER-MD-CONFIG: e1e8a2fd-e40a-4ac6-ac9b-f7e9cc9ee180 Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Certain platforms like TI's J721E using Cadence PCIe IP can perform only 32-bit accesses for reading or writing to Cadence registers. Convert all read and write accesses to 32-bit in Cadence PCIe driver in preparation for adding PCIe support in TI's J721E SoC. Also add spin lock to disable interrupts while modifying PCI_STATUS register while raising legacy interrupt since PCI_STATUS is accessible by both remote RC and EP and time between read and write should be minimized. Signed-off-by: Kishon Vijay Abraham I --- .../pci/controller/cadence/pcie-cadence-ep.c | 4 + drivers/pci/controller/cadence/pcie-cadence.h | 76 ++++++++++++++----- 2 files changed, 62 insertions(+), 18 deletions(-) diff --git a/drivers/pci/controller/cadence/pcie-cadence-ep.c b/drivers/pci/controller/cadence/pcie-cadence-ep.c index 4a829ccff7d0..c6eb2db94680 100644 --- a/drivers/pci/controller/cadence/pcie-cadence-ep.c +++ b/drivers/pci/controller/cadence/pcie-cadence-ep.c @@ -228,6 +228,7 @@ static void cdns_pcie_ep_assert_intx(struct cdns_pcie_ep *ep, u8 fn, u8 intx, bool is_asserted) { struct cdns_pcie *pcie = &ep->pcie; + unsigned long flags; u32 offset; u16 status; u8 msg_code; @@ -252,11 +253,13 @@ static void cdns_pcie_ep_assert_intx(struct cdns_pcie_ep *ep, u8 fn, msg_code = MSG_CODE_DEASSERT_INTA + intx; } + spin_lock_irqsave(&ep->lock, flags); status = cdns_pcie_ep_fn_readw(pcie, fn, PCI_STATUS); if (((status & PCI_STATUS_INTERRUPT) != 0) ^ (ep->irq_pending != 0)) { status ^= PCI_STATUS_INTERRUPT; cdns_pcie_ep_fn_writew(pcie, fn, PCI_STATUS, status); } + spin_unlock_irqrestore(&ep->lock, flags); offset = CDNS_PCIE_NORMAL_MSG_ROUTING(MSG_ROUTING_LOCAL) | CDNS_PCIE_NORMAL_MSG_CODE(msg_code) | @@ -464,6 +467,7 @@ int cdns_pcie_ep_setup(struct cdns_pcie_ep *ep) ep->irq_pci_addr = CDNS_PCIE_EP_IRQ_PCI_ADDR_NONE; /* Reserve region 0 for IRQs */ set_bit(0, &ep->ob_region_map); + spin_lock_init(&ep->lock); return 0; diff --git a/drivers/pci/controller/cadence/pcie-cadence.h b/drivers/pci/controller/cadence/pcie-cadence.h index bc49c22e48a9..a45c11158f49 100644 --- a/drivers/pci/controller/cadence/pcie-cadence.h +++ b/drivers/pci/controller/cadence/pcie-cadence.h @@ -304,6 +304,9 @@ struct cdns_pcie_rc { * @irq_pci_fn: the latest PCI function that has updated the mapping of * the MSI/legacy IRQ dedicated outbound region. * @irq_pending: bitmask of asserted legacy IRQs. + * @lock: spin lock to disable interrupts while modifying PCIe controller + * registers fields (RMW) accessible by both remote RC and EP to + * minimize time between read and write */ struct cdns_pcie_ep { struct cdns_pcie pcie; @@ -315,54 +318,94 @@ struct cdns_pcie_ep { u64 irq_pci_addr; u8 irq_pci_fn; u8 irq_pending; + /* protect writing to PCI_STATUS while raising legacy interrupts */ + spinlock_t lock; }; /* Register access */ -static inline void cdns_pcie_writeb(struct cdns_pcie *pcie, u32 reg, u8 value) +static inline void cdns_pcie_writel(struct cdns_pcie *pcie, u32 reg, u32 value) { - writeb(value, pcie->reg_base + reg); + writel(value, pcie->reg_base + reg); } -static inline void cdns_pcie_writew(struct cdns_pcie *pcie, u32 reg, u16 value) +static inline u32 cdns_pcie_readl(struct cdns_pcie *pcie, u32 reg) { - writew(value, pcie->reg_base + reg); + return readl(pcie->reg_base + reg); } -static inline void cdns_pcie_writel(struct cdns_pcie *pcie, u32 reg, u32 value) +static inline u32 cdns_pcie_read_sz(void __iomem *addr, int size) { - writel(value, pcie->reg_base + reg); + void __iomem *aligned_addr = PTR_ALIGN_DOWN(addr, 0x4); + unsigned int offset = (unsigned long)addr & 0x3; + u32 val = readl(aligned_addr); + + if (!IS_ALIGNED((uintptr_t)addr, size)) { + WARN(1, "Address %p and size %d are not aligned\n", addr, size); + return 0; + } + + if (size > 2) + return val; + + return (val >> (8 * offset)) & ((1 << (size * 8)) - 1); } -static inline u32 cdns_pcie_readl(struct cdns_pcie *pcie, u32 reg) +static inline void cdns_pcie_write_sz(void __iomem *addr, int size, u32 value) { - return readl(pcie->reg_base + reg); + void __iomem *aligned_addr = PTR_ALIGN_DOWN(addr, 0x4); + unsigned int offset = (unsigned long)addr & 0x3; + u32 mask; + u32 val; + + if (!IS_ALIGNED((uintptr_t)addr, size)) { + WARN(1, "Address %p and size %d are not aligned\n", addr, size); + return; + } + + if (size > 2) { + writel(value, addr); + return; + } + + mask = ~(((1 << (size * 8)) - 1) << (offset * 8)); + val = readl(aligned_addr) & mask; + val |= value << (offset * 8); + writel(val, aligned_addr); } /* Root Port register access */ static inline void cdns_pcie_rp_writeb(struct cdns_pcie *pcie, u32 reg, u8 value) { - writeb(value, pcie->reg_base + CDNS_PCIE_RP_BASE + reg); + void __iomem *addr = pcie->reg_base + CDNS_PCIE_RP_BASE + reg; + + cdns_pcie_write_sz(addr, 0x1, value); } static inline void cdns_pcie_rp_writew(struct cdns_pcie *pcie, u32 reg, u16 value) { - writew(value, pcie->reg_base + CDNS_PCIE_RP_BASE + reg); + void __iomem *addr = pcie->reg_base + CDNS_PCIE_RP_BASE + reg; + + cdns_pcie_write_sz(addr, 0x2, value); } /* Endpoint Function register access */ static inline void cdns_pcie_ep_fn_writeb(struct cdns_pcie *pcie, u8 fn, u32 reg, u8 value) { - writeb(value, pcie->reg_base + CDNS_PCIE_EP_FUNC_BASE(fn) + reg); + void __iomem *addr = pcie->reg_base + CDNS_PCIE_EP_FUNC_BASE(fn) + reg; + + cdns_pcie_write_sz(addr, 0x1, value); } static inline void cdns_pcie_ep_fn_writew(struct cdns_pcie *pcie, u8 fn, u32 reg, u16 value) { - writew(value, pcie->reg_base + CDNS_PCIE_EP_FUNC_BASE(fn) + reg); + void __iomem *addr = pcie->reg_base + CDNS_PCIE_EP_FUNC_BASE(fn) + reg; + + cdns_pcie_write_sz(addr, 0x2, value); } static inline void cdns_pcie_ep_fn_writel(struct cdns_pcie *pcie, u8 fn, @@ -371,14 +414,11 @@ static inline void cdns_pcie_ep_fn_writel(struct cdns_pcie *pcie, u8 fn, writel(value, pcie->reg_base + CDNS_PCIE_EP_FUNC_BASE(fn) + reg); } -static inline u8 cdns_pcie_ep_fn_readb(struct cdns_pcie *pcie, u8 fn, u32 reg) -{ - return readb(pcie->reg_base + CDNS_PCIE_EP_FUNC_BASE(fn) + reg); -} - static inline u16 cdns_pcie_ep_fn_readw(struct cdns_pcie *pcie, u8 fn, u32 reg) { - return readw(pcie->reg_base + CDNS_PCIE_EP_FUNC_BASE(fn) + reg); + void __iomem *addr = pcie->reg_base + CDNS_PCIE_EP_FUNC_BASE(fn) + reg; + + return cdns_pcie_read_sz(addr, 0x2); } static inline u32 cdns_pcie_ep_fn_readl(struct cdns_pcie *pcie, u8 fn, u32 reg)