Date: Wed, 14 Feb 2024 10:23:56 -0800 From: John Baldwin <jhb@FreeBSD.org> To: Mark Millard <marklmi@yahoo.com> Cc: FreeBSD ARM List <freebsd-arm@freebsd.org>, Current FreeBSD <freebsd-current@freebsd.org>, Warner Losh <imp@bsdimp.com> Subject: Re: Recent commits reject RPi4B booting: pcib0 vs. pcib1 "rman_manage_region: <pcib1 memory window> request" leads to panic Message-ID: <0b0ba1b0-dee5-47e2-bb93-b44a24492abd@FreeBSD.org> In-Reply-To: <CCA368C1-C8D7-4B54-999D-6F709C4E5039@yahoo.com> References: <76AB969F-5BC5-4116-8AF4-3ED2CABEBBA5.ref@yahoo.com> <76AB969F-5BC5-4116-8AF4-3ED2CABEBBA5@yahoo.com> <f4326cda-c602-439f-ab03-f66b3bca5ff2@FreeBSD.org> <1F704317-FDB8-4BDA-8A67-61CF48794DFE@yahoo.com> <9AFDF067-96E4-4E67-90D2-F40DAF3F138F@yahoo.com> <4C279710-5F88-4295-B1A4-7C395F3587E5@yahoo.com> <3A145420-399D-4EBD-9FF4-18924908AB1D@yahoo.com> <1298DF9C-0F82-4567-8E81-7332A608C7FC@yahoo.com> <d7b20565-6aa1-486f-a197-11fbc4d0c8dd@FreeBSD.org> <36ECB040-7E09-47A9-AF71-DE546A78E9CA@yahoo.com> <CCA368C1-C8D7-4B54-999D-6F709C4E5039@yahoo.com>
next in thread | previous in thread | raw e-mail | index | archive | help
On 2/14/24 10:16 AM, Mark Millard wrote: > Top posting a related but separate item: > > I looked up some old (2022-Dec-17) lspci -v output from > a Linux boot. Note the "Memory at" value 600000000 (in > the 35 bit BCM2711 address space) and the "(64-bit, > non-prefetchable)" (and "[size=4K]"). > > 01:00.0 USB controller: VIA Technologies, Inc. VL805/806 xHCI USB 3.0 Controller (rev 01) (prog-if 30 [XHCI]) > Subsystem: VIA Technologies, Inc. VL805/806 xHCI USB 3.0 Controller > Device tree node: /sys/firmware/devicetree/base/scb/pcie@7d500000/pci@0,0/usb@0,0 > Flags: bus master, fast devsel, latency 0, IRQ 51 > Memory at 600000000 (64-bit, non-prefetchable) [size=4K] > Capabilities: [80] Power Management version 3 > Capabilities: [90] MSI: Enable+ Count=1/4 Maskable- 64bit+ > Capabilities: [c4] Express Endpoint, MSI 00 > Capabilities: [100] Advanced Error Reporting > Kernel driver in use: xhci_hcd > > > "Memory at 600000000 (64-bit, non-prefetchable)": > Violation of a PCIe standard? No, this is a device BAR which can be 64-bit (memory BARs can either be 32-bits or 64-bits). However, the "window" in a PCI _bridge_ for memory is only defined to be 32-bits. Windows in PCI-PCI bridges are a special type of BAR that defines the address ranges that the bridge decodes on the parent side and passes down to child devices. The prefetchable window in PCI-PCI bridges can optionally be 64-bit. BAR == a range of memory or I/O port addresses decoded by a device, usually mapped to a register bank, but sometimes mapped to internal memory (e.g. a framebuffer) Window == a range of memory or I/O port addresses decoded by a bridge for which transactions are passed across the bridge to be handled by a child device. -- John Baldwin
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?0b0ba1b0-dee5-47e2-bb93-b44a24492abd>