arch/tile: core support for Tilera 32-bit chips.

This change is the core kernel support for TILEPro and TILE64 chips.
No driver support (except the console driver) is included yet.

This includes the relevant Linux headers in asm/; the low-level
low-level "Tile architecture" headers in arch/, which are
shared with the hypervisor, etc., and are build-system agnostic;
and the relevant hypervisor headers in hv/.

Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Reviewed-by: Paul Mundt <lethal@linux-sh.org>

1 files changed, 211 insertions, 0 deletions

diff --git a/arch/tile/mm/migrate_32.S b/arch/tile/mm/migrate_32.S
new file mode 100644
index 0000000..f738765
--- /dev/null
+++ b/arch/tile/mm/migrate_32.S
@@ -0,0 +1,211 @@
+/*
+ * Copyright 2010 Tilera Corporation. All Rights Reserved.
+ *
+ *   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, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful, but
+ *   WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
+ *   NON INFRINGEMENT.  See the GNU General Public License for
+ *   more details.
+ *
+ * This routine is a helper for migrating the home of a set of pages to
+ * a new cpu.  See the documentation in homecache.c for more information.
+ */
+
+#include <linux/linkage.h>
+#include <linux/threads.h>
+#include <asm/page.h>
+#include <asm/types.h>
+#include <asm/asm-offsets.h>
+#include <hv/hypervisor.h>
+
+	.text
+
+/*
+ * First, some definitions that apply to all the code in the file.
+ */
+
+/* Locals (caller-save) */
+#define r_tmp		r10
+#define r_save_sp	r11
+
+/* What we save where in the stack frame; must include all callee-saves. */
+#define FRAME_SP	4
+#define FRAME_R30	8
+#define FRAME_R31	12
+#define FRAME_R32	16
+#define FRAME_R33	20
+#define FRAME_R34	24
+#define FRAME_R35	28
+#define FRAME_SIZE	32
+
+
+
+
+/*
+ * On entry:
+ *
+ *   r0 low word of the new context PA to install (moved to r_context_lo)
+ *   r1 high word of the new context PA to install (moved to r_context_hi)
+ *   r2 low word of PTE to use for context access (moved to r_access_lo)
+ *   r3 high word of PTE to use for context access (moved to r_access_lo)
+ *   r4 ASID to use for new context (moved to r_asid)
+ *   r5 pointer to cpumask with just this cpu set in it (r_my_cpumask)
+ */
+
+/* Arguments (caller-save) */
+#define r_context_lo_in	r0
+#define r_context_hi_in	r1
+#define r_access_lo_in	r2
+#define r_access_hi_in	r3
+#define r_asid_in	r4
+#define r_my_cpumask	r5
+
+/* Locals (callee-save); must not be more than FRAME_xxx above. */
+#define r_save_ics	r30
+#define r_context_lo	r31
+#define r_context_hi	r32
+#define r_access_lo	r33
+#define r_access_hi	r34
+#define r_asid		r35
+
+STD_ENTRY(flush_and_install_context)
+	/*
+	 * Create a stack frame; we can't touch it once we flush the
+	 * cache until we install the new page table and flush the TLB.
+	 */
+	{
+	 move r_save_sp, sp
+	 sw sp, lr
+	 addi sp, sp, -FRAME_SIZE
+	}
+	addi r_tmp, sp, FRAME_SP
+	{
+	 sw r_tmp, r_save_sp
+	 addi r_tmp, sp, FRAME_R30
+	}
+	{
+	 sw r_tmp, r30
+	 addi r_tmp, sp, FRAME_R31
+	}
+	{
+	 sw r_tmp, r31
+	 addi r_tmp, sp, FRAME_R32
+	}
+	{
+	 sw r_tmp, r32
+	 addi r_tmp, sp, FRAME_R33
+	}
+	{
+	 sw r_tmp, r33
+	 addi r_tmp, sp, FRAME_R34
+	}
+	{
+	 sw r_tmp, r34
+	 addi r_tmp, sp, FRAME_R35
+	}
+	sw r_tmp, r35
+
+	/* Move some arguments to callee-save registers. */
+	{
+	 move r_context_lo, r_context_lo_in
+	 move r_context_hi, r_context_hi_in
+	}
+	{
+	 move r_access_lo, r_access_lo_in
+	 move r_access_hi, r_access_hi_in
+	}
+	move r_asid, r_asid_in
+
+	/* Disable interrupts, since we can't use our stack. */
+	{
+	 mfspr r_save_ics, INTERRUPT_CRITICAL_SECTION
+	 movei r_tmp, 1
+	}
+	mtspr INTERRUPT_CRITICAL_SECTION, r_tmp
+
+	/* First, flush our L2 cache. */
+	{
+	 move r0, zero  /* cache_pa */
+	 move r1, zero
+	}
+	{
+	 auli r2, zero, ha16(HV_FLUSH_EVICT_L2)  /* cache_control */
+	 move r3, r_my_cpumask  /* cache_cpumask */
+	}
+	{
+	 move r4, zero  /* tlb_va */
+	 move r5, zero  /* tlb_length */
+	}
+	{
+	 move r6, zero  /* tlb_pgsize */
+	 move r7, zero  /* tlb_cpumask */
+	}
+	{
+	 move r8, zero  /* asids */
+	 move r9, zero  /* asidcount */
+	}
+	jal hv_flush_remote
+	bnz r0, .Ldone
+
+	/* Now install the new page table. */
+	{
+	 move r0, r_context_lo
+	 move r1, r_context_hi
+	}
+	{
+	 move r2, r_access_lo
+	 move r3, r_access_hi
+	}
+	{
+	 move r4, r_asid
+	 movei r5, HV_CTX_DIRECTIO
+	}
+	jal hv_install_context
+	bnz r0, .Ldone
+
+	/* Finally, flush the TLB. */
+	{
+	 movei r0, 0   /* preserve_global */
+	 jal hv_flush_all
+	}
+
+.Ldone:
+	/* Reset interrupts back how they were before. */
+	mtspr INTERRUPT_CRITICAL_SECTION, r_save_ics
+
+	/* Restore the callee-saved registers and return. */
+	addli lr, sp, FRAME_SIZE
+	{
+	 lw lr, lr
+	 addli r_tmp, sp, FRAME_R30
+	}
+	{
+	 lw r30, r_tmp
+	 addli r_tmp, sp, FRAME_R31
+	}
+	{
+	 lw r31, r_tmp
+	 addli r_tmp, sp, FRAME_R32
+	}
+	{
+	 lw r32, r_tmp
+	 addli r_tmp, sp, FRAME_R33
+	}
+	{
+	 lw r33, r_tmp
+	 addli r_tmp, sp, FRAME_R34
+	}
+	{
+	 lw r34, r_tmp
+	 addli r_tmp, sp, FRAME_R35
+	}
+	{
+	 lw r35, r_tmp
+	 addi sp, sp, FRAME_SIZE
+	}
+	jrp lr
+	STD_ENDPROC(flush_and_install_context)