ppb(4) related changes

[Masanobu SAITOH <msaitoh%execsw.org@localhost>]

 Hi.

 I'm now working to modify PCI bridge stuff. I'd like to do the following
two modifications:

 0) ppbreg.h definitions

    All of PCI configuration space's register definitions are in pcireg.h
    The ppbreg.h file also defines the same config registers. I think it's
    good to remove ppbreg.hs' definitions an use pcireg.h's definitions.
    Is it OK?

 1) Mis-configuration of prefetchable memory in pciconf.c::configure_bridge()
    (only for PCI_NETBSD_CONFIGURE)

    In configure_bridge():

>         mem = pci_conf_read(pb->pc, pd->tag, PCI_BRIDGE_PREFETCHMEM_REG);

	Read register

> #if ULONG_MAX > 0xffffffff
>         if (!PCI_BRIDGE_PREFETCHMEM_64BITS(mem) && mem_limit > 0xFFFFFFFFULL) {

	Test if it's marked as 64bit (the maring is in lower 4bit)

>                 printf("Bus %d bridge does not support 64-bit PMEM.  ",
>                     pb->busno);
>                 printf("Disabling prefetchable-MEM accesses\n");
>                 mem_base  = 0x100000;   /* 1M */
>                 mem_limit = 0x000000;
>         }
> #endif
>         mem = (((mem_base >> 20) & PCI_BRIDGE_PREFETCHMEM_BASE_MASK)
>             << PCI_BRIDGE_PREFETCHMEM_BASE_SHIFT);
>         mem |= (((mem_limit >> 20) & PCI_BRIDGE_PREFETCHMEM_LIMIT_MASK)
>             << PCI_BRIDGE_PREFETCHMEM_LIMIT_SHIFT);
>         pci_conf_write(pb->pc, pd->tag, PCI_BRIDGE_PREFETCHMEM_REG, mem);

	Regenerate mem value from scratch _WITHOUT_SETTING_LOWER_4BITS_
	(It's OK because the lower 4bit is read only).

>         /*
>          * XXX -- 64-bit systems need a lot more than just this...
>          */
>         if (PCI_BRIDGE_PREFETCHMEM_64BITS(mem)) {

	Test if it's marked as 64bit or not. It must be wrong because "mem"
	is not the original value, newly generated and low 4bits are 0.
	It should always be false.

>                 mem_base  = (uint64_t) mem_base  >> 32;
>                 mem_limit = (uint64_t) mem_limit >> 32;
>                 pci_conf_write(pb->pc, pd->tag, PCI_BRIDGE_PREFETCHBASE32_REG,
>                     mem_base & 0xffffffff);
>                 pci_conf_write(pb->pc, pd->tag, PCI_BRIDGE_PREFETCHLIMIT32_REG,
>                     mem_limit & 0xffffffff);
>         }

	So, proposed patch:
--------------
Index: pciconf.c
===================================================================
RCS file: /cvsroot/src/sys/dev/pci/pciconf.c,v
retrieving revision 1.37
diff -u -p -r1.37 pciconf.c
--- pciconf.c	5 Sep 2014 05:29:16 -0000	1.37
+++ pciconf.c	28 Jan 2019 10:30:13 -0000
@@ -855,6 +855,7 @@ configure_bridge(pciconf_dev_t *pd)
 	pciconf_bus_t	*pb;
 	pcireg_t	io, iohigh, mem, cmd;
 	int		rv;
+	bool		isprefetchmem64;
 
 	pb = pd->ppb;
 	/* Configure I/O base & limit*/
@@ -919,8 +920,9 @@ configure_bridge(pciconf_dev_t *pd)
 		mem_limit = 0x000000;
 	}
 	mem = pci_conf_read(pb->pc, pd->tag, PCI_BRIDGE_PREFETCHMEM_REG);
+	isprefetchmem64 = PCI_BRIDGE_PREFETCHMEM_64BITS(mem);
 #if ULONG_MAX > 0xffffffff
-	if (!PCI_BRIDGE_PREFETCHMEM_64BITS(mem) && mem_limit > 0xFFFFFFFFULL) {
+	if (!isprefetchmem64 && mem_limit > 0xFFFFFFFFULL) {
 		printf("Bus %d bridge does not support 64-bit PMEM.  ",
 		    pb->busno);
 		printf("Disabling prefetchable-MEM accesses\n");
@@ -936,7 +938,7 @@ configure_bridge(pciconf_dev_t *pd)
 	/*
 	 * XXX -- 64-bit systems need a lot more than just this...
 	 */
-	if (PCI_BRIDGE_PREFETCHMEM_64BITS(mem)) {
+	if (isprefetchmem64) {
 		mem_base  = (uint64_t) mem_base  >> 32;
 		mem_limit = (uint64_t) mem_limit >> 32;
 		pci_conf_write(pb->pc, pd->tag, PCI_BRIDGE_PREFETCHBASE32_REG,
--------------

	I can't test this diff because I have no any machine which can test
	PCI_NETBSD_CONFIGURE now. Is it OK to commit without test?

--
-----------------------------------------------
                SAITOH Masanobu (msaitoh%execsw.org@localhost
                                 msaitoh%netbsd.org@localhost)