Thread (84 messages) 84 messages, 12 authors, 2017-01-07

Re: [PATCH V5 3/3] ARM64 LPC: LPC driver implementation on Hip06

From: Arnd Bergmann <arnd@arndb.de>
Date: 2016-11-09 21:37:26
Also in: linux-arm-kernel, linux-pci, linux-serial, lkml

On Wednesday, November 9, 2016 12:10:43 PM CET Gabriele Paoloni wrote:
quoted
On Tuesday, November 8, 2016 11:47:09 AM CET zhichang.yuan wrote:
quoted
+       /*
+        * The first PCIBIOS_MIN_IO is reserved specifically for
indirectIO.
quoted
+        * It will separate indirectIO range from pci host bridge to
+        * avoid the possible PIO conflict.
+        * Set the indirectIO range directly here.
+        */
+       lpcdev->io_ops.start = 0;
+       lpcdev->io_ops.end = PCIBIOS_MIN_IO - 1;
+       lpcdev->io_ops.devpara = lpcdev;
+       lpcdev->io_ops.pfin = hisilpc_comm_in;
+       lpcdev->io_ops.pfout = hisilpc_comm_out;
+       lpcdev->io_ops.pfins = hisilpc_comm_ins;
+       lpcdev->io_ops.pfouts = hisilpc_comm_outs;
I have to look at patch 2 in more detail again, after missing a few
review
rounds. I'm still a bit skeptical about hardcoding a logical I/O port
range here, and would hope that we can just go through the same
assignment of logical port ranges that we have for PCI buses,
decoupling
the bus addresses from the linux-internal ones.
The point here is that we want to avoid any conflict/overlap between
the LPC I/O space and the PCI I/O space. With the assignment above
we make sure that LPC never interfere with PCI I/O space.
But we already abstract the PCI I/O space using dynamic registration.
There is no need to hardcode the logical address for ISA, though
I think we can hardcode the bus address to start at zero here.

	Arnd
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help