[kvm-unit-tests PATCH v3 05/17] arm/arm64: setup improvements

[Andrew Jones <drjones@redhat.com>]

Handle multiple memory regions being described in the DT. Also
add a more informative error message for when a user does -smp N,
N > NR_CPUS.

Signed-off-by: Andrew Jones <drjones@redhat.com>

---
powerpc will adapt arm's setup to be used as it's own, and it
needs these changes. There's no reason to only do them for power,
so we do them in arm first, getting them ready to be adapted.
---
 lib/arm/asm/setup.h |  9 ++++++++
 lib/arm/setup.c     | 66 ++++++++++++++++++++++++++++++++++++++---------------
 2 files changed, 56 insertions(+), 19 deletions(-)

diff --git a/lib/arm/asm/setup.h b/lib/arm/asm/setup.h
index 02b668672fca4..cb8fdbd38dd5d 100644
--- a/lib/arm/asm/setup.h
+++ b/lib/arm/asm/setup.h
@@ -6,6 +6,7 @@
  * This work is licensed under the terms of the GNU LGPL, version 2.
  */
 #include <libcflat.h>
+#include <alloc.h>	/* phys_addr_t */
 #include <asm/page.h>
 #include <asm/pgtable-hwdef.h>
 
@@ -13,6 +14,14 @@
 extern u32 cpus[NR_CPUS];
 extern int nr_cpus;
 
+#define NR_MEM_REGIONS		8
+#define MR_F_PRIMARY		(1U << 0)
+struct mem_region {
+	phys_addr_t start;
+	phys_addr_t end;
+	unsigned int flags;
+};
+extern struct mem_region mem_regions[NR_MEM_REGIONS];
 extern phys_addr_t __phys_offset, __phys_end;
 
 #define PHYS_OFFSET		(__phys_offset)
diff --git a/lib/arm/setup.c b/lib/arm/setup.c
index da6edc1f9d8ff..8c6172ff94106 100644
--- a/lib/arm/setup.c
+++ b/lib/arm/setup.c
@@ -27,12 +27,18 @@ extern void setup_args(const char *args);
 u32 cpus[NR_CPUS] = { [0 ... NR_CPUS-1] = (~0U) };
 int nr_cpus;
 
+struct mem_region mem_regions[NR_MEM_REGIONS];
 phys_addr_t __phys_offset, __phys_end;
 
 static void cpu_set(int fdtnode __unused, u32 regval, void *info __unused)
 {
 	int cpu = nr_cpus++;
-	assert(cpu < NR_CPUS);
+
+	if (cpu >= NR_CPUS) {
+		printf("Number cpus exceeds maximum supported (%d).\n",
+			NR_CPUS);
+		assert(0);
+	}
 	cpus[cpu] = regval;
 	set_cpu_present(cpu, true);
 }
@@ -49,24 +55,46 @@ static void cpu_init(void)
 
 static void mem_init(phys_addr_t freemem_start)
 {
-	/* we only expect one membank to be defined in the DT */
-	struct dt_pbus_reg regs[1];
-	phys_addr_t mem_start, mem_end;
-	int ret;
-
-	ret = dt_get_memory_params(regs, 1);
-	assert(ret != 0);
-
-	mem_start = regs[0].addr;
-	mem_end = mem_start + regs[0].size;
-
-	assert(!(mem_start & ~PHYS_MASK) && !((mem_end-1) & ~PHYS_MASK));
-	assert(freemem_start >= mem_start && freemem_start < mem_end);
-
-	__phys_offset = mem_start;	/* PHYS_OFFSET */
-	__phys_end = mem_end;		/* PHYS_END */
-
-	phys_alloc_init(freemem_start, mem_end - freemem_start);
+	struct dt_pbus_reg regs[NR_MEM_REGIONS];
+	struct mem_region primary, mem = {
+		.start = (phys_addr_t)-1,
+	};
+	int nr_regs, i;
+
+	nr_regs = dt_get_memory_params(regs, NR_MEM_REGIONS);
+	assert(nr_regs > 0);
+
+	primary.end = 0;
+
+	for (i = 0; i < nr_regs; ++i) {
+		mem_regions[i].start = regs[i].addr;
+		mem_regions[i].end = regs[i].addr + regs[i].size;
+
+		/*
+		 * pick the region we're in for our primary region
+		 */
+		if (freemem_start >= mem_regions[i].start
+				&& freemem_start < mem_regions[i].end) {
+			mem_regions[i].flags |= MR_F_PRIMARY;
+			primary = mem_regions[i];
+		}
+
+		/*
+		 * set the lowest and highest addresses found,
+		 * ignoring potential gaps
+		 */
+		if (mem_regions[i].start < mem.start)
+			mem.start = mem_regions[i].start;
+		if (mem_regions[i].end > mem.end)
+			mem.end = mem_regions[i].end;
+	}
+	assert(primary.end != 0);
+	assert(!(mem.start & ~PHYS_MASK) && !((mem.end - 1) & ~PHYS_MASK));
+
+	__phys_offset = mem.start;	/* PHYS_OFFSET */
+	__phys_end = mem.end;		/* PHYS_END */
+
+	phys_alloc_init(freemem_start, primary.end - freemem_start);
 	phys_alloc_set_minimum_alignment(SMP_CACHE_BYTES);
 
 	mmu_enable_idmap();
-- 
2.4.3