From patchwork Sat Mar 30 04:19:13 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Damien Le Moal X-Patchwork-Id: 13611456 X-Patchwork-Delegate: manivannanece23@gmail.com Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 262161FA5; Sat, 30 Mar 2024 04:19:41 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711772382; cv=none; b=LximgIL5v2fSVIx6D9+PFfQZ8f9v5qrElTwVSvJjRWF8bUBW4v5UVvvOoDiHMIzq5PXuUpAHDVB7vI6SA5C186HX/iWWYm8W084eOO2Dk1FFLxAIOQOb/Qj9+UJhuLfUYRMggP8GATdefoElY5kjvu5nqITN9s0mPcT8lDMcUjg= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711772382; c=relaxed/simple; bh=Ao001csYCN6yZIStO43McU0FezoXkwzy4CBDoV75mOI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=QVU39RwrEG6Lywuxs4BZ08vcfquA7qeHEvYwgJ6yJxW/sj49cuE3aa8NVhSodOQlHFlmHNhfaaRkd1nOmV9NrEFDiStQ1d3KyIJ588wVaNiPytfzwd8V36VzZC6muV8osa5peTTfTzKm7hBeP3TbA6IXOMX+Yqp7GipKRuWjSSw= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=n0rVtTAd; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="n0rVtTAd" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C1927C43390; Sat, 30 Mar 2024 04:19:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1711772381; bh=Ao001csYCN6yZIStO43McU0FezoXkwzy4CBDoV75mOI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=n0rVtTAdEHncI7btaISmeCrHohnNnZimfSjh8u0BHMWyGEtIOyJngOaFDTYXLUkf5 8knQ6x5u9cqpjFgu+BfDqpqYcn8AdVNcYzpkuZcV1b6AXG5dCFeynAD+d2wm/Jmmya nBi51Ma1IiysY1PX47uuTCjh+eO+IW0NfrLlXkdUvP9+VxohyeH+01OBl6k/OysM2n UoTFaPgwzkn0keVOcfa87qVht6Fawv8oCaHdABq2gXsNx3HnJLuCtMt3YMqj2t74RJ gfKAkOdWngT0ucv6Ynd8Qs7ROtijXpAQ87nx+pdYdYEA1CtAuKgZlYjwM5and9pF7w 9nfn29KCNxbTg== From: Damien Le Moal To: Manivannan Sadhasivam , Lorenzo Pieralisi , Kishon Vijay Abraham I , Shawn Lin , =?utf-8?q?Krzysztof_Wilczy=C5=84ski?= , Bjorn Helgaas , Heiko Stuebner , linux-pci@vger.kernel.org, Rob Herring , Krzysztof Kozlowski , Conor Dooley , devicetree@vger.kernel.org Cc: linux-rockchip@lists.infradead.org, linux-arm-kernel@lists.infradead.org, Rick Wertenbroek , Wilfred Mallawa , Niklas Cassel Subject: [PATCH v2 03/18] PCI: endpoint: Introduce pci_epc_mem_map()/unmap() Date: Sat, 30 Mar 2024 13:19:13 +0900 Message-ID: <20240330041928.1555578-4-dlemoal@kernel.org> X-Mailer: git-send-email 2.44.0 In-Reply-To: <20240330041928.1555578-1-dlemoal@kernel.org> References: <20240330041928.1555578-1-dlemoal@kernel.org> Precedence: bulk X-Mailing-List: linux-pci@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Introduce the function pci_epc_mem_map() to facilitate controller memory address allocation and mapping to a RC PCI address region in endpoint function drivers. This function first uses pci_epc_map_align() to determine the controller memory address alignment (offset and size) constraints. The result of this function is used to allocate a controller physical memory region using pci_epc_mem_alloc_addr() and map it to the RC PCI address space with pci_epc_map_addr(). Since pci_epc_map_align() may indicate that a mapping can be smaller than the requested size, pci_epc_mem_map() may only partially map the RC PCI address region specified and return a smaller size for the effective mapping. The counterpart of pci_epc_mem_map() to unmap and free the controller memory address region is pci_epc_mem_unmap(). Both functions operate using struct pci_epc_map data structure which is extended to contain the physical and virtual addresses of the allocated controller memory. Endpoint function drivers can use struct pci_epc_map to implement read/write accesses within the mapped RC PCI address region using the ->virt_addr and ->size fields. This commit contains contributions from Rick Wertenbroek . Signed-off-by: Damien Le Moal --- drivers/pci/endpoint/pci-epc-core.c | 68 +++++++++++++++++++++++++++++ include/linux/pci-epc.h | 6 +++ 2 files changed, 74 insertions(+) diff --git a/drivers/pci/endpoint/pci-epc-core.c b/drivers/pci/endpoint/pci-epc-core.c index 37758ca91d7f..0095b54bdf9e 100644 --- a/drivers/pci/endpoint/pci-epc-core.c +++ b/drivers/pci/endpoint/pci-epc-core.c @@ -530,6 +530,74 @@ int pci_epc_map_addr(struct pci_epc *epc, u8 func_no, u8 vfunc_no, } EXPORT_SYMBOL_GPL(pci_epc_map_addr); +/** + * pci_epc_mem_map() - allocate and map CPU address to PCI address + * @epc: the EPC device on which the CPU address is to be allocated and mapped + * @func_no: the physical endpoint function number in the EPC device + * @vfunc_no: the virtual endpoint function number in the physical function + * @pci_addr: PCI address to which the CPU address should be mapped + * @size: the number of bytes to map starting from @pci_addr + * @map: where to return the mapping information + * + * Allocate a controller physical address region and map it to a RC PCI address + * region, taking into account the controller physical address mapping + * constraints (if any). Returns the effective size of the mapping, which may + * be less than @size, or a negative error code in case of error. + */ +ssize_t pci_epc_mem_map(struct pci_epc *epc, u8 func_no, u8 vfunc_no, + u64 pci_addr, size_t size, struct pci_epc_map *map) +{ + int ret; + + ret = pci_epc_map_align(epc, func_no, vfunc_no, pci_addr, size, map); + if (ret) + return ret; + + map->virt_base = pci_epc_mem_alloc_addr(epc, &map->phys_base, + map->map_size); + if (!map->virt_base) + return -ENOMEM; + + map->phys_addr = map->phys_base + map->map_ofst; + map->virt_addr = map->virt_base + map->map_ofst; + + ret = pci_epc_map_addr(epc, func_no, vfunc_no, map->phys_base, + map->map_pci_addr, map->map_size); + if (ret) { + pci_epc_mem_free_addr(epc, map->phys_base, map->virt_base, + map->map_size); + return ret; + } + + return map->pci_size; +} +EXPORT_SYMBOL_GPL(pci_epc_mem_map); + +/** + * pci_epc_mem_unmap() - unmap from PCI address and free a CPU address region + * @epc: the EPC device on which the CPU address is allocated and mapped + * @func_no: the physical endpoint function number in the EPC device + * @vfunc_no: the virtual endpoint function number in the physical function + * @map: the mapping information + * + * Allocate and map local CPU address to a PCI address, accounting for the + * controller local CPU address alignment constraints. + */ +void pci_epc_mem_unmap(struct pci_epc *epc, u8 func_no, u8 vfunc_no, + struct pci_epc_map *map) +{ + if (!pci_epc_function_is_valid(epc, func_no, vfunc_no)) + return; + + if (!map || !map->pci_size) + return; + + pci_epc_unmap_addr(epc, func_no, vfunc_no, map->phys_base); + pci_epc_mem_free_addr(epc, map->phys_base, map->virt_base, + map->map_size); +} +EXPORT_SYMBOL_GPL(pci_epc_mem_unmap); + /** * pci_epc_clear_bar() - reset the BAR * @epc: the EPC device for which the BAR has to be cleared diff --git a/include/linux/pci-epc.h b/include/linux/pci-epc.h index 8cfb4aaf2628..86397a500b54 100644 --- a/include/linux/pci-epc.h +++ b/include/linux/pci-epc.h @@ -304,4 +304,10 @@ void __iomem *pci_epc_mem_alloc_addr(struct pci_epc *epc, phys_addr_t *phys_addr, size_t size); void pci_epc_mem_free_addr(struct pci_epc *epc, phys_addr_t phys_addr, void __iomem *virt_addr, size_t size); + +ssize_t pci_epc_mem_map(struct pci_epc *epc, u8 func_no, u8 vfunc_no, + u64 pci_addr, size_t size, struct pci_epc_map *map); +void pci_epc_mem_unmap(struct pci_epc *epc, u8 func_no, u8 vfunc_no, + struct pci_epc_map *map); + #endif /* __LINUX_PCI_EPC_H */