tile: parameterize VA and PA space more cleanly

The existing code relied on the hardware definition (<arch/chip.h>)
to specify how much VA and PA space was available.  It's convenient
to allow customizing this for some configurations, so provide symbols
MAX_PA_WIDTH and MAX_VA_WIDTH in <asm/page.h> that can be modified
if desired.

Additionally, move away from the MEM_XX_INTRPT nomenclature to
define the start of various regions within the VA space.  In fact
the cleaner symbol is, for example, MEM_SV_START, to indicate the
start of the area used for supervisor code; the actual address of the
interrupt vectors is not as important, and can be changed if desired.
As part of this change, convert from "intrpt1" nomenclature (which
built in the old privilege-level 1 model) to a simple "intrpt".

Also strip out some tilepro-specific code supporting modifying the
PL the kernel could run at, since we don't actually support using
different PLs in tilepro, only tilegx.

Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>

7 files changed, 23 insertions, 21 deletions

diff --git a/arch/tile/kernel/head_32.S b/arch/tile/kernel/head_32.S
index f3f17b0..8d5b40f 100644
--- a/arch/tile/kernel/head_32.S
+++ b/arch/tile/kernel/head_32.S
@@ -162,8 +162,8 @@ ENTRY(swapper_pg_dir)
 	.set addr, addr + PGDIR_SIZE
 	.endr
 
-	/* The true text VAs are mapped as VA = PA + MEM_SV_INTRPT */
-	PTE MEM_SV_INTRPT, 0, (1 << (HV_PTE_INDEX_READABLE - 32)) | \
+	/* The true text VAs are mapped as VA = PA + MEM_SV_START */
+	PTE MEM_SV_START, 0, (1 << (HV_PTE_INDEX_READABLE - 32)) | \
 			      (1 << (HV_PTE_INDEX_EXECUTABLE - 32))
 	.org swapper_pg_dir + PGDIR_SIZE
 	END(swapper_pg_dir)
diff --git a/arch/tile/kernel/head_64.S b/arch/tile/kernel/head_64.S
index 652b814..bd0e12f 100644
--- a/arch/tile/kernel/head_64.S
+++ b/arch/tile/kernel/head_64.S
@@ -135,9 +135,9 @@ ENTRY(_start)
 1:
 
 	/* Install the interrupt base. */
-	moveli r0, hw2_last(MEM_SV_START)
-	shl16insli r0, r0, hw1(MEM_SV_START)
-	shl16insli r0, r0, hw0(MEM_SV_START)
+	moveli r0, hw2_last(intrpt_start)
+	shl16insli r0, r0, hw1(intrpt_start)
+	shl16insli r0, r0, hw0(intrpt_start)
 	mtspr SPR_INTERRUPT_VECTOR_BASE_K, r0
 
 	/* Get our processor number and save it away in SAVE_K_0. */
diff --git a/arch/tile/kernel/intvec_32.S b/arch/tile/kernel/intvec_32.S
index f3d26f4..f084f1c 100644
--- a/arch/tile/kernel/intvec_32.S
+++ b/arch/tile/kernel/intvec_32.S
@@ -353,7 +353,7 @@ intvec_\vecname:
 #ifdef __COLLECT_LINKER_FEEDBACK__
 	.pushsection .text.intvec_feedback,"ax"
 	.org    (\vecnum << 5)
-	FEEDBACK_ENTER_EXPLICIT(intvec_\vecname, .intrpt1, 1 << 8)
+	FEEDBACK_ENTER_EXPLICIT(intvec_\vecname, .intrpt, 1 << 8)
 	jrp     lr
 	.popsection
 #endif
@@ -1890,8 +1890,8 @@ int_unalign:
 	push_extra_callee_saves r0
 	j       do_trap
 
-/* Include .intrpt1 array of interrupt vectors */
-	.section ".intrpt1", "ax"
+/* Include .intrpt array of interrupt vectors */
+	.section ".intrpt", "ax"
 
 #define op_handle_perf_interrupt bad_intr
 #define op_handle_aux_perf_interrupt bad_intr
diff --git a/arch/tile/kernel/intvec_64.S b/arch/tile/kernel/intvec_64.S
index f020f01..c3a2335 100644
--- a/arch/tile/kernel/intvec_64.S
+++ b/arch/tile/kernel/intvec_64.S
@@ -535,7 +535,7 @@ intvec_\vecname:
 #ifdef __COLLECT_LINKER_FEEDBACK__
 	.pushsection .text.intvec_feedback,"ax"
 	.org    (\vecnum << 5)
-	FEEDBACK_ENTER_EXPLICIT(intvec_\vecname, .intrpt1, 1 << 8)
+	FEEDBACK_ENTER_EXPLICIT(intvec_\vecname, .intrpt, 1 << 8)
 	jrp     lr
 	.popsection
 #endif
@@ -1485,8 +1485,10 @@ STD_ENTRY(fill_ra_stack)
 		__int_hand   \vecnum, \vecname, \c_routine, \processing
 	.endm
 
-/* Include .intrpt1 array of interrupt vectors */
-	.section ".intrpt1", "ax"
+/* Include .intrpt array of interrupt vectors */
+	.section ".intrpt", "ax"
+	.global intrpt_start
+intrpt_start:
 
 #define op_handle_perf_interrupt bad_intr
 #define op_handle_aux_perf_interrupt bad_intr
diff --git a/arch/tile/kernel/setup.c b/arch/tile/kernel/setup.c
index 774e819..1021784 100644
--- a/arch/tile/kernel/setup.c
+++ b/arch/tile/kernel/setup.c
@@ -268,7 +268,7 @@ early_param("vmalloc", parse_vmalloc);
 /*
  * Determine for each controller where its lowmem is mapped and how much of
  * it is mapped there.  On controller zero, the first few megabytes are
- * already mapped in as code at MEM_SV_INTRPT, so in principle we could
+ * already mapped in as code at MEM_SV_START, so in principle we could
  * start our data mappings higher up, but for now we don't bother, to avoid
  * additional confusion.
  *
@@ -1242,7 +1242,7 @@ static void __init validate_va(void)
 #ifndef __tilegx__   /* FIXME: GX: probably some validation relevant here */
 	/*
 	 * Similarly, make sure we're only using allowed VAs.
-	 * We assume we can contiguously use MEM_USER_INTRPT .. MEM_HV_INTRPT,
+	 * We assume we can contiguously use MEM_USER_INTRPT .. MEM_HV_START,
 	 * and 0 .. KERNEL_HIGH_VADDR.
 	 * In addition, make sure we CAN'T use the end of memory, since
 	 * we use the last chunk of each pgd for the pgd_list.
@@ -1257,7 +1257,7 @@ static void __init validate_va(void)
 		if (range.size == 0)
 			break;
 		if (range.start <= MEM_USER_INTRPT &&
-		    range.start + range.size >= MEM_HV_INTRPT)
+		    range.start + range.size >= MEM_HV_START)
 			user_kernel_ok = 1;
 		if (range.start == 0)
 			max_va = range.size;
@@ -1693,7 +1693,7 @@ insert_ram_resource(u64 start_pfn, u64 end_pfn, bool reserved)
 static int __init request_standard_resources(void)
 {
 	int i;
-	enum { CODE_DELTA = MEM_SV_INTRPT - PAGE_OFFSET };
+	enum { CODE_DELTA = MEM_SV_START - PAGE_OFFSET };
 
 #if defined(CONFIG_PCI) && !defined(__tilegx__)
 	insert_non_bus_resource();
diff --git a/arch/tile/kernel/traps.c b/arch/tile/kernel/traps.c
index cfff6f9..628661f 100644
--- a/arch/tile/kernel/traps.c
+++ b/arch/tile/kernel/traps.c
@@ -30,7 +30,7 @@
 
 void __init trap_init(void)
 {
-	/* Nothing needed here since we link code at .intrpt1 */
+	/* Nothing needed here since we link code at .intrpt */
 }
 
 int unaligned_fixup = 1;
diff --git a/arch/tile/kernel/vmlinux.lds.S b/arch/tile/kernel/vmlinux.lds.S
index c7ae53d..8b20163 100644
--- a/arch/tile/kernel/vmlinux.lds.S
+++ b/arch/tile/kernel/vmlinux.lds.S
@@ -5,7 +5,7 @@
 #include <hv/hypervisor.h>
 
 /* Text loads starting from the supervisor interrupt vector address. */
-#define TEXT_OFFSET MEM_SV_INTRPT
+#define TEXT_OFFSET MEM_SV_START
 
 OUTPUT_ARCH(tile)
 ENTRY(_start)
@@ -13,7 +13,7 @@ jiffies = jiffies_64;
 
 PHDRS
 {
-  intrpt1 PT_LOAD ;
+  intrpt PT_LOAD ;
   text PT_LOAD ;
   data PT_LOAD ;
 }
@@ -24,11 +24,11 @@ SECTIONS
   #define LOAD_OFFSET TEXT_OFFSET
 
   /* Interrupt vectors */
-  .intrpt1 (LOAD_OFFSET) : AT ( 0 )   /* put at the start of physical memory */
+  .intrpt (LOAD_OFFSET) : AT ( 0 )   /* put at the start of physical memory */
   {
     _text = .;
-    *(.intrpt1)
-  } :intrpt1 =0
+    *(.intrpt)
+  } :intrpt =0
 
   /* Hypervisor call vectors */
   . = ALIGN(0x10000);