ofwfb: fix vga/hdmi console with ASMEDIA during boot on powerpc64(le)

On recent OpenBMC firmware, the onboard ASMEDIA video card framebuffer
address was removed from device tree for security purposes (value is set
to zero to avoid leaking the address).

This patch works around the problem by taking framebuffer base address
from the "ranges" property of a parent node.

Reviewed by:	luporl, jhibbits (on IRC)
MFC after:	2 weeks
Sponsored by:	Instituto de Pesquisas Eldorado (eldorado.org.br)
Differential Revision:	https://reviews.freebsd.org/D30626
This commit is contained in:
Alfredo Dal'Ava Junior 2021-11-03 13:42:28 -03:00
parent e4ce23b238
commit b042d10cdc

View file

@ -61,7 +61,8 @@ struct ofwfb_softc {
uint32_t vendor_id;
};
#define PCI_VENDOR_ID_NVIDIA 0x10de
#define PCI_VID_NVIDIA 0x10de /* NVIDIA Corporation */
#define PCI_VID_ASPEED 0x1a03 /* ASPEED Technology, Inc. */
static void ofwfb_initialize(struct vt_device *vd);
static vd_probe_t ofwfb_probe;
@ -297,6 +298,104 @@ ofwfb_bitblt_text(struct vt_device *vd, const struct vt_window *vw,
#endif
}
/*
* Decode OpenFirmware/IEEE 1275-1994 "ranges" property
*
* XXX: this is similar to ofw_pcib_fill_ranges but cannot use it here because
* it's not possible to allocate memory at the moment this is funcion is
* used. Since there are other similar functions dealing with "ranges"
* property, a proper refactoring is suggested.
*/
static uint64_t
decode_pci_ranges_host_addr(phandle_t pcinode)
{
struct simplebus_range {
uint64_t bus;
uint64_t host;
uint64_t size;
};
struct simplebus_range ranges[4];
int nranges, host_address_cells;
pcell_t acells, scells;
cell_t base_ranges[64];
ssize_t nbase_ranges;
int i, j, k;
if (!OF_hasprop(pcinode, "ranges"))
return (0);
if (OF_getencprop(pcinode, "#address-cells", &acells, sizeof(acells)) !=
sizeof(acells))
return (0);
if (OF_getencprop(pcinode, "#size-cells", &scells, sizeof(scells)) !=
sizeof(scells))
return (0);
if (OF_searchencprop(OF_parent(pcinode), "#address-cells",
&host_address_cells, sizeof(host_address_cells)) !=
sizeof(host_address_cells))
return (0);
nbase_ranges = OF_getproplen(pcinode, "ranges");
nranges = nbase_ranges / sizeof(cell_t) / (acells + host_address_cells + scells);
/* prevent buffer overflow during iteration */
if (nranges > sizeof(ranges) / sizeof(ranges[0]))
nranges = sizeof(ranges) / sizeof(ranges[0]);
/* decode range value and return the first valid address */
OF_getencprop(pcinode, "ranges", base_ranges, nbase_ranges);
for (i = 0, j = 0; i < nranges; i++) {
ranges[i].bus = 0;
for (k = 0; k < acells; k++) {
ranges[i].bus <<= 32;
ranges[i].bus |= base_ranges[j++];
}
ranges[i].host = 0;
for (k = 0; k < host_address_cells; k++) {
ranges[i].host <<= 32;
ranges[i].host |= base_ranges[j++];
}
ranges[i].size = 0;
for (k = 0; k < scells; k++) {
ranges[i].size <<= 32;
ranges[i].size |= base_ranges[j++];
}
if (ranges[i].host != 0)
return (ranges[i].host);
}
return (0);
}
static bus_addr_t
find_pci_host_address(phandle_t node)
{
uint64_t addr;
/*
* According to IEEE STD 1275, if property "ranges" exists but has a
* zero-length property value, the child address space is identical
* to the parent address space.
*/
while (node) {
if (OF_hasprop(node, "ranges")) {
addr = decode_pci_ranges_host_addr(node);
if (addr != 0)
return ((bus_addr_t)addr);
}
node = OF_parent(node);
}
return (0);
}
static void
ofwfb_initialize(struct vt_device *vd)
{
@ -350,7 +449,7 @@ ofwfb_initialize(struct vt_device *vd)
* There is no good way to determine the correct option, as this
* is independent of endian swapping.
*/
if (sc->vendor_id == PCI_VENDOR_ID_NVIDIA)
if (sc->vendor_id == PCI_VID_NVIDIA)
sc->argb = 0;
else
sc->argb = 1;
@ -430,7 +529,6 @@ ofwfb_init(struct vt_device *vd)
sizeof(vendor_id)) == sizeof(vendor_id))
sc->vendor_id = vendor_id;
/* Keep track of the OF node */
sc->sc_node = node;
@ -497,12 +595,18 @@ ofwfb_init(struct vt_device *vd)
* Grab the physical address of the framebuffer, and then map it
* into our memory space. If the MMU is not yet up, it will be
* remapped for us when relocation turns on.
*
* The ASPEED driver on recent petitboot versions doesn't expose the
* physical address of framebuffer anymore for security. So it should
* retrieve the address from PCI device properties.
*/
user_phys = 0;
TUNABLE_UINT64_FETCH("hw.ofwfb.physaddr", &user_phys);
fb_phys = (bus_addr_t)user_phys;
if (fb_phys)
sc->fb.fb_pbase = (vm_paddr_t)fb_phys;
if (user_phys)
sc->fb.fb_pbase = (vm_paddr_t)user_phys;
else if (sc->vendor_id == PCI_VID_ASPEED)
sc->fb.fb_pbase = find_pci_host_address(node);
else if (OF_hasprop(node, "address")) {
switch (OF_getproplen(node, "address")) {