powerpc/powernv: Add PIO accessors for Power8 LPC bus
This uses the hooks provided by CONFIG_PPC_INDIRECT_PIO to
implement a set of hooks for IO port access to use the LPC
bus via OPAL calls for the first 64K of IO space
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
diff --git a/arch/powerpc/platforms/powernv/opal-lpc.c b/arch/powerpc/platforms/powernv/opal-lpc.c
new file mode 100644
index 0000000..a7614bb
--- /dev/null
+++ b/arch/powerpc/platforms/powernv/opal-lpc.c
@@ -0,0 +1,203 @@
+/*
+ * PowerNV LPC bus handling.
+ *
+ * Copyright 2013 IBM Corp.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/kernel.h>
+#include <linux/of.h>
+#include <linux/bug.h>
+
+#include <asm/machdep.h>
+#include <asm/firmware.h>
+#include <asm/xics.h>
+#include <asm/opal.h>
+
+static int opal_lpc_chip_id = -1;
+
+static u8 opal_lpc_inb(unsigned long port)
+{
+ int64_t rc;
+ uint32_t data;
+
+ if (opal_lpc_chip_id < 0 || port > 0xffff)
+ return 0xff;
+ rc = opal_lpc_read(opal_lpc_chip_id, OPAL_LPC_IO, port, &data, 1);
+ return rc ? 0xff : data;
+}
+
+static __le16 __opal_lpc_inw(unsigned long port)
+{
+ int64_t rc;
+ uint32_t data;
+
+ if (opal_lpc_chip_id < 0 || port > 0xfffe)
+ return 0xffff;
+ if (port & 1)
+ return (__le16)opal_lpc_inb(port) << 8 | opal_lpc_inb(port + 1);
+ rc = opal_lpc_read(opal_lpc_chip_id, OPAL_LPC_IO, port, &data, 2);
+ return rc ? 0xffff : data;
+}
+static u16 opal_lpc_inw(unsigned long port)
+{
+ return le16_to_cpu(__opal_lpc_inw(port));
+}
+
+static __le32 __opal_lpc_inl(unsigned long port)
+{
+ int64_t rc;
+ uint32_t data;
+
+ if (opal_lpc_chip_id < 0 || port > 0xfffc)
+ return 0xffffffff;
+ if (port & 3)
+ return (__le32)opal_lpc_inb(port ) << 24 |
+ (__le32)opal_lpc_inb(port + 1) << 16 |
+ (__le32)opal_lpc_inb(port + 2) << 8 |
+ opal_lpc_inb(port + 3);
+ rc = opal_lpc_read(opal_lpc_chip_id, OPAL_LPC_IO, port, &data, 4);
+ return rc ? 0xffffffff : data;
+}
+
+static u32 opal_lpc_inl(unsigned long port)
+{
+ return le32_to_cpu(__opal_lpc_inl(port));
+}
+
+static void opal_lpc_outb(u8 val, unsigned long port)
+{
+ if (opal_lpc_chip_id < 0 || port > 0xffff)
+ return;
+ opal_lpc_write(opal_lpc_chip_id, OPAL_LPC_IO, port, val, 1);
+}
+
+static void __opal_lpc_outw(__le16 val, unsigned long port)
+{
+ if (opal_lpc_chip_id < 0 || port > 0xfffe)
+ return;
+ if (port & 1) {
+ opal_lpc_outb(val >> 8, port);
+ opal_lpc_outb(val , port + 1);
+ return;
+ }
+ opal_lpc_write(opal_lpc_chip_id, OPAL_LPC_IO, port, val, 2);
+}
+
+static void opal_lpc_outw(u16 val, unsigned long port)
+{
+ __opal_lpc_outw(cpu_to_le16(val), port);
+}
+
+static void __opal_lpc_outl(__le32 val, unsigned long port)
+{
+ if (opal_lpc_chip_id < 0 || port > 0xfffc)
+ return;
+ if (port & 3) {
+ opal_lpc_outb(val >> 24, port);
+ opal_lpc_outb(val >> 16, port + 1);
+ opal_lpc_outb(val >> 8, port + 2);
+ opal_lpc_outb(val , port + 3);
+ return;
+ }
+ opal_lpc_write(opal_lpc_chip_id, OPAL_LPC_IO, port, val, 4);
+}
+
+static void opal_lpc_outl(u32 val, unsigned long port)
+{
+ __opal_lpc_outl(cpu_to_le32(val), port);
+}
+
+static void opal_lpc_insb(unsigned long p, void *b, unsigned long c)
+{
+ u8 *ptr = b;
+
+ while(c--)
+ *(ptr++) = opal_lpc_inb(p);
+}
+
+static void opal_lpc_insw(unsigned long p, void *b, unsigned long c)
+{
+ __le16 *ptr = b;
+
+ while(c--)
+ *(ptr++) = __opal_lpc_inw(p);
+}
+
+static void opal_lpc_insl(unsigned long p, void *b, unsigned long c)
+{
+ __le32 *ptr = b;
+
+ while(c--)
+ *(ptr++) = __opal_lpc_inl(p);
+}
+
+static void opal_lpc_outsb(unsigned long p, const void *b, unsigned long c)
+{
+ const u8 *ptr = b;
+
+ while(c--)
+ opal_lpc_outb(*(ptr++), p);
+}
+
+static void opal_lpc_outsw(unsigned long p, const void *b, unsigned long c)
+{
+ const __le16 *ptr = b;
+
+ while(c--)
+ __opal_lpc_outw(*(ptr++), p);
+}
+
+static void opal_lpc_outsl(unsigned long p, const void *b, unsigned long c)
+{
+ const __le32 *ptr = b;
+
+ while(c--)
+ __opal_lpc_outl(*(ptr++), p);
+}
+
+static const struct ppc_pci_io opal_lpc_io = {
+ .inb = opal_lpc_inb,
+ .inw = opal_lpc_inw,
+ .inl = opal_lpc_inl,
+ .outb = opal_lpc_outb,
+ .outw = opal_lpc_outw,
+ .outl = opal_lpc_outl,
+ .insb = opal_lpc_insb,
+ .insw = opal_lpc_insw,
+ .insl = opal_lpc_insl,
+ .outsb = opal_lpc_outsb,
+ .outsw = opal_lpc_outsw,
+ .outsl = opal_lpc_outsl,
+};
+
+void opal_lpc_init(void)
+{
+ struct device_node *np;
+
+ /*
+ * Look for a Power8 LPC bus tagged as "primary",
+ * we currently support only one though the OPAL APIs
+ * support any number.
+ */
+ for_each_compatible_node(np, NULL, "ibm,power8-lpc") {
+ if (!of_device_is_available(np))
+ continue;
+ if (!of_get_property(np, "primary", NULL))
+ continue;
+ opal_lpc_chip_id = of_get_ibm_chip_id(np);
+ break;
+ }
+ if (opal_lpc_chip_id < 0)
+ return;
+
+ /* Setup special IO ops */
+ ppc_pci_io = opal_lpc_io;
+ isa_io_special = true;
+
+ pr_info("OPAL: Power8 LPC bus found, chip ID %d\n", opal_lpc_chip_id);
+}