Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
diff --git a/arch/mips/sgi-ip27/ip27-hubio.c b/arch/mips/sgi-ip27/ip27-hubio.c
new file mode 100644
index 0000000..524b371
--- /dev/null
+++ b/arch/mips/sgi-ip27/ip27-hubio.c
@@ -0,0 +1,186 @@
+/*
+ * Copyright (C) 1992-1997, 2000-2003 Silicon Graphics, Inc.
+ * Copyright (C) 2004 Christoph Hellwig.
+ * Released under GPL v2.
+ *
+ * Support functions for the HUB ASIC - mostly PIO mapping related.
+ */
+
+#include <linux/bitops.h>
+#include <linux/string.h>
+#include <linux/mmzone.h>
+#include <asm/sn/addrs.h>
+#include <asm/sn/arch.h>
+#include <asm/sn/hub.h>
+
+
+static int force_fire_and_forget = 1;
+
+/**
+ * hub_pio_map - establish a HUB PIO mapping
+ *
+ * @hub: hub to perform PIO mapping on
+ * @widget: widget ID to perform PIO mapping for
+ * @xtalk_addr: xtalk_address that needs to be mapped
+ * @size: size of the PIO mapping
+ *
+ **/
+unsigned long hub_pio_map(cnodeid_t cnode, xwidgetnum_t widget,
+ unsigned long xtalk_addr, size_t size)
+{
+ nasid_t nasid = COMPACT_TO_NASID_NODEID(cnode);
+ volatile hubreg_t junk;
+ unsigned i;
+
+ /* use small-window mapping if possible */
+ if ((xtalk_addr % SWIN_SIZE) + size <= SWIN_SIZE)
+ return NODE_SWIN_BASE(nasid, widget) + (xtalk_addr % SWIN_SIZE);
+
+ if ((xtalk_addr % BWIN_SIZE) + size > BWIN_SIZE) {
+ printk(KERN_WARNING "PIO mapping at hub %d widget %d addr 0x%lx"
+ " too big (%ld)\n",
+ nasid, widget, xtalk_addr, size);
+ return 0;
+ }
+
+ xtalk_addr &= ~(BWIN_SIZE-1);
+ for (i = 0; i < HUB_NUM_BIG_WINDOW; i++) {
+ if (test_and_set_bit(i, hub_data(cnode)->h_bigwin_used))
+ continue;
+
+ /*
+ * The code below does a PIO write to setup an ITTE entry.
+ *
+ * We need to prevent other CPUs from seeing our updated
+ * memory shadow of the ITTE (in the piomap) until the ITTE
+ * entry is actually set up; otherwise, another CPU might
+ * attempt a PIO prematurely.
+ *
+ * Also, the only way we can know that an entry has been
+ * received by the hub and can be used by future PIO reads/
+ * writes is by reading back the ITTE entry after writing it.
+ *
+ * For these two reasons, we PIO read back the ITTE entry
+ * after we write it.
+ */
+ IIO_ITTE_PUT(nasid, i, HUB_PIO_MAP_TO_MEM, widget, xtalk_addr);
+ junk = HUB_L(IIO_ITTE_GET(nasid, i));
+
+ return NODE_BWIN_BASE(nasid, widget) + (xtalk_addr % BWIN_SIZE);
+ }
+
+ printk(KERN_WARNING "unable to establish PIO mapping for at"
+ " hub %d widget %d addr 0x%lx\n",
+ nasid, widget, xtalk_addr);
+ return 0;
+}
+
+
+/*
+ * hub_setup_prb(nasid, prbnum, credits, conveyor)
+ *
+ * Put a PRB into fire-and-forget mode if conveyor isn't set. Otherwise,
+ * put it into conveyor belt mode with the specified number of credits.
+ */
+static void hub_setup_prb(nasid_t nasid, int prbnum, int credits)
+{
+ iprb_t prb;
+ int prb_offset;
+
+ /*
+ * Get the current register value.
+ */
+ prb_offset = IIO_IOPRB(prbnum);
+ prb.iprb_regval = REMOTE_HUB_L(nasid, prb_offset);
+
+ /*
+ * Clear out some fields.
+ */
+ prb.iprb_ovflow = 1;
+ prb.iprb_bnakctr = 0;
+ prb.iprb_anakctr = 0;
+
+ /*
+ * Enable or disable fire-and-forget mode.
+ */
+ prb.iprb_ff = force_fire_and_forget ? 1 : 0;
+
+ /*
+ * Set the appropriate number of PIO cresits for the widget.
+ */
+ prb.iprb_xtalkctr = credits;
+
+ /*
+ * Store the new value to the register.
+ */
+ REMOTE_HUB_S(nasid, prb_offset, prb.iprb_regval);
+}
+
+/**
+ * hub_set_piomode - set pio mode for a given hub
+ *
+ * @nasid: physical node ID for the hub in question
+ *
+ * Put the hub into either "PIO conveyor belt" mode or "fire-and-forget" mode.
+ * To do this, we have to make absolutely sure that no PIOs are in progress
+ * so we turn off access to all widgets for the duration of the function.
+ *
+ * XXX - This code should really check what kind of widget we're talking
+ * to. Bridges can only handle three requests, but XG will do more.
+ * How many can crossbow handle to widget 0? We're assuming 1.
+ *
+ * XXX - There is a bug in the crossbow that link reset PIOs do not
+ * return write responses. The easiest solution to this problem is to
+ * leave widget 0 (xbow) in fire-and-forget mode at all times. This
+ * only affects pio's to xbow registers, which should be rare.
+ **/
+static void hub_set_piomode(nasid_t nasid)
+{
+ hubreg_t ii_iowa;
+ hubii_wcr_t ii_wcr;
+ unsigned i;
+
+ ii_iowa = REMOTE_HUB_L(nasid, IIO_OUTWIDGET_ACCESS);
+ REMOTE_HUB_S(nasid, IIO_OUTWIDGET_ACCESS, 0);
+
+ ii_wcr.wcr_reg_value = REMOTE_HUB_L(nasid, IIO_WCR);
+
+ if (ii_wcr.iwcr_dir_con) {
+ /*
+ * Assume a bridge here.
+ */
+ hub_setup_prb(nasid, 0, 3);
+ } else {
+ /*
+ * Assume a crossbow here.
+ */
+ hub_setup_prb(nasid, 0, 1);
+ }
+
+ /*
+ * XXX - Here's where we should take the widget type into
+ * when account assigning credits.
+ */
+ for (i = HUB_WIDGET_ID_MIN; i <= HUB_WIDGET_ID_MAX; i++)
+ hub_setup_prb(nasid, i, 3);
+
+ REMOTE_HUB_S(nasid, IIO_OUTWIDGET_ACCESS, ii_iowa);
+}
+
+/*
+ * hub_pio_init - PIO-related hub initalization
+ *
+ * @hub: hubinfo structure for our hub
+ */
+void hub_pio_init(cnodeid_t cnode)
+{
+ nasid_t nasid = COMPACT_TO_NASID_NODEID(cnode);
+ unsigned i;
+
+ /* initialize big window piomaps for this hub */
+ bitmap_zero(hub_data(cnode)->h_bigwin_used, HUB_NUM_BIG_WINDOW);
+ for (i = 0; i < HUB_NUM_BIG_WINDOW; i++)
+ IIO_ITTE_DISABLE(nasid, i);
+
+ hub_set_piomode(nasid);
+}