Date: Fri, 29 Aug 2003 14:16:41 -0700 From: Marcel Moolenaar <marcel@xcllnt.net> To: sparc64@FreeBSD.org Subject: Q: resource range for SBus oddity Message-ID: <20030829211641.GA628@athlon.pn.xcllnt.net>
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Gang, I'm playing with uart(4) on Jake's u2, which has 2 zs(4) devices attached to sbus. A GENERIC kernel gives me the following: : zs0: <Zilog Z8530> mem 0x1100000-0x1100003 irq 2024 on sbus0 zstty0: <ttya> on zs0 zstty0: console 9600,8,n,1,- zstty1: <ttyb> on zs0 sbus0: <zs>, type serial (no driver attached) : A kernel with uart(4) yields currently (it's a WIP): : puc0: <Zilog Z8530 dual channel SCC> mem 0x1100000-0x1100003 irq 2024 on sbus0 uart0: <Zilog Z8530 dual channel SCC> on puc0 uart0: console uart1: <Zilog Z8530 dual channel SCC> on puc0 puc1: <Zilog Z8530 dual channel SCC> mem 0x1000000-0x1000003 irq 2024 on sbus0 uart2: <Zilog Z8530 dual channel SCC> on puc1 uart3: <Zilog Z8530 dual channel SCC> on puc1 : As you can see, the memory I/O resource is 4 bytes wide. However, the channel A registers on the z8530 chip are at offsets 4 (control) and 6 (data). This lies outside the reserved range. I would think that with 2 channels and 2 addressable registers per channel we would be using offsets 0-3. Question: Is there an implied multiplication or division factor? -- Marcel Moolenaar USPA: A-39004 marcel@xcllnt.net
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