Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit b3c711a9 authored by Benjamin Herrenschmidt's avatar Benjamin Herrenschmidt Committed by Michael Ellerman
Browse files

powerpc: Add support for non-PCI ISA bridges 



The POWER9 chip supports an LPC bus that isn't hanging
off a PCI bus, so let's add support for that, mapping it
to the reserved space at ISA_IO_BASE

Signed-off-by: default avatarBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
parent 38e9d36b

arch/powerpc/include/asm/isa-bridge.h

+1 −0
Original line number Diff line number Diff line
@@ -4,6 +4,7 @@ 
#ifdef CONFIG_PPC64



extern void isa_bridge_find_early(struct pci_controller *hose);

extern void isa_bridge_init_non_pci(struct device_node *np);



static inline int isa_vaddr_is_ioport(void __iomem *address)

{

arch/powerpc/kernel/isa-bridge.c

+91 −0
Original line number Diff line number Diff line
@@ -167,6 +167,97 @@ void __init isa_bridge_find_early(struct pci_controller *hose) 
	pr_debug("ISA bridge (early) is %s\n", np->full_name);

}



/**

 * isa_bridge_find_early - Find and map the ISA IO space early before

 *                         main PCI discovery. This is optionally called by

 *                         the arch code when adding PCI PHBs to get early

 *                         access to ISA IO ports

 */

void __init isa_bridge_init_non_pci(struct device_node *np)

{

	const __be32 *ranges, *pbasep = NULL;

	int rlen, i, rs;

	u32 na, ns, pna;

	u64 cbase, pbase, size = 0;



	/* If we already have an ISA bridge, bail off */

	if (isa_bridge_devnode != NULL)

		return;



	pna = of_n_addr_cells(np);

	if (of_property_read_u32(np, "#address-cells", &na) ||

	    of_property_read_u32(np, "#size-cells", &ns)) {

		pr_warn("ISA: Non-PCI bridge %s is missing address format\n",

			np->full_name);

		return;

	}



	/* Check it's a supported address format */

	if (na != 2 || ns != 1) {

		pr_warn("ISA: Non-PCI bridge %s has unsupported address format\n",

			np->full_name);

		return;

	}

	rs = na + ns + pna;



	/* Grab the ranges property */

	ranges = of_get_property(np, "ranges", &rlen);

	if (ranges == NULL || rlen < rs) {

		pr_warn("ISA: Non-PCI bridge %s has absent or invalid ranges\n",

			np->full_name);

		return;

	}



	/* Parse it. We are only looking for IO space */

	for (i = 0; (i + rs - 1) < rlen; i += rs) {

		if (be32_to_cpup(ranges + i) != 1)

			continue;

		cbase = be32_to_cpup(ranges + i + 1);

		size = of_read_number(ranges + i + na + pna, ns);

		pbasep = ranges + i + na;

		break;

	}



	/* Got something ? */

	if (!size || !pbasep) {

		pr_warn("ISA: Non-PCI bridge %s has no usable IO range\n",

			np->full_name);

		return;

	}



	/* Align size and make sure it's cropped to 64K */

	size = PAGE_ALIGN(size);

	if (size > 0x10000)

		size = 0x10000;



	/* Map pbase */

	pbase = of_translate_address(np, pbasep);

	if (pbase == OF_BAD_ADDR) {

		pr_warn("ISA: Non-PCI bridge %s failed to translate IO base\n",

			np->full_name);

		return;

	}



	/* We need page alignment */

	if ((cbase & ~PAGE_MASK) || (pbase & ~PAGE_MASK)) {

		pr_warn("ISA: Non-PCI bridge %s has non aligned IO range\n",

			np->full_name);

		return;

	}



	/* Got it */

	isa_bridge_devnode = np;



	/* Set the global ISA io base to indicate we have an ISA bridge

	 * and map it

	 */

	isa_io_base = ISA_IO_BASE;

	__ioremap_at(pbase, (void *)ISA_IO_BASE,

		     size, pgprot_val(pgprot_noncached(__pgprot(0))));



	pr_debug("ISA: Non-PCI bridge is %s\n", np->full_name);

}



/**

 * isa_bridge_find_late - Find and map the ISA IO space upon discovery of

 *                        a new ISA bridge