lib: lmb: extend lmb for checks at load time

This adds two new functions, lmb_alloc_addr and
lmb_get_unreserved_size.

lmb_alloc_addr behaves like lmb_alloc, but it tries to allocate a
pre-specified address range. Unlike lmb_reserve, this address range
must be inside one of the memory ranges that has been set up with
lmb_add.

lmb_get_unreserved_size returns the number of bytes that can be
used up to the next reserved region or the end of valid ram. This
can be 0 if the address passed is reserved.

Added test for these new functions.

Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Simon Goldschmidt <simon.k.r.goldschmidt@gmail.com>

3 files changed, 258 insertions, 0 deletions

diff --git a/include/lmb.h b/include/lmb.h
index f04d058093..7d7e2a78dc 100644
--- a/include/lmb.h
+++ b/include/lmb.h
@@ -38,6 +38,9 @@ extern phys_addr_t lmb_alloc_base(struct lmb *lmb, phys_size_t size, ulong align
 			    phys_addr_t max_addr);
 extern phys_addr_t __lmb_alloc_base(struct lmb *lmb, phys_size_t size, ulong align,
 			      phys_addr_t max_addr);
+extern phys_addr_t lmb_alloc_addr(struct lmb *lmb, phys_addr_t base,
+				  phys_size_t size);
+extern phys_size_t lmb_get_unreserved_size(struct lmb *lmb, phys_addr_t addr);
 extern int lmb_is_reserved(struct lmb *lmb, phys_addr_t addr);
 extern long lmb_free(struct lmb *lmb, phys_addr_t base, phys_size_t size);
 
diff --git a/lib/lmb.c b/lib/lmb.c
index cd297f8202..e380a0a722 100644
--- a/lib/lmb.c
+++ b/lib/lmb.c
@@ -313,6 +313,59 @@ phys_addr_t __lmb_alloc_base(struct lmb *lmb, phys_size_t size, ulong align, phy
 	return 0;
 }
 
+/*
+ * Try to allocate a specific address range: must be in defined memory but not
+ * reserved
+ */
+phys_addr_t lmb_alloc_addr(struct lmb *lmb, phys_addr_t base, phys_size_t size)
+{
+	long j;
+
+	/* Check if the requested address is in one of the memory regions */
+	j = lmb_overlaps_region(&lmb->memory, base, size);
+	if (j >= 0) {
+		/*
+		 * Check if the requested end address is in the same memory
+		 * region we found.
+		 */
+		if (lmb_addrs_overlap(lmb->memory.region[j].base,
+				      lmb->memory.region[j].size, base + size -
+				      1, 1)) {
+			/* ok, reserve the memory */
+			if (lmb_reserve(lmb, base, size) >= 0)
+				return base;
+		}
+	}
+	return 0;
+}
+
+/* Return number of bytes from a given address that are free */
+phys_size_t lmb_get_unreserved_size(struct lmb *lmb, phys_addr_t addr)
+{
+	int i;
+	long j;
+
+	/* check if the requested address is in the memory regions */
+	j = lmb_overlaps_region(&lmb->memory, addr, 1);
+	if (j >= 0) {
+		for (i = 0; i < lmb->reserved.cnt; i++) {
+			if (addr < lmb->reserved.region[i].base) {
+				/* first reserved range > requested address */
+				return lmb->reserved.region[i].base - addr;
+			}
+			if (lmb->reserved.region[i].base +
+			    lmb->reserved.region[i].size > addr) {
+				/* requested addr is in this reserved range */
+				return 0;
+			}
+		}
+		/* if we come here: no reserved ranges above requested addr */
+		return lmb->memory.region[lmb->memory.cnt - 1].base +
+		       lmb->memory.region[lmb->memory.cnt - 1].size - addr;
+	}
+	return 0;
+}
+
 int lmb_is_reserved(struct lmb *lmb, phys_addr_t addr)
 {
 	int i;
diff --git a/test/lib/lmb.c b/test/lib/lmb.c
index e6acb70e76..058d3c332b 100644
--- a/test/lib/lmb.c
+++ b/test/lib/lmb.c
@@ -397,3 +397,205 @@ static int lib_test_lmb_overlapping_reserve(struct unit_test_state *uts)
 
 DM_TEST(lib_test_lmb_overlapping_reserve,
 	DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT);
+
+/*
+ * Simulate 512 MiB RAM, reserve 3 blocks, allocate addresses in between.
+ * Expect addresses outside the memory range to fail.
+ */
+static int test_alloc_addr(struct unit_test_state *uts, const phys_addr_t ram)
+{
+	const phys_size_t ram_size = 0x20000000;
+	const phys_addr_t ram_end = ram + ram_size;
+	const phys_size_t alloc_addr_a = ram + 0x8000000;
+	const phys_size_t alloc_addr_b = ram + 0x8000000 * 2;
+	const phys_size_t alloc_addr_c = ram + 0x8000000 * 3;
+	struct lmb lmb;
+	long ret;
+	phys_addr_t a, b, c, d, e;
+
+	/* check for overflow */
+	ut_assert(ram_end == 0 || ram_end > ram);
+
+	lmb_init(&lmb);
+
+	ret = lmb_add(&lmb, ram, ram_size);
+	ut_asserteq(ret, 0);
+
+	/*  reserve 3 blocks */
+	ret = lmb_reserve(&lmb, alloc_addr_a, 0x10000);
+	ut_asserteq(ret, 0);
+	ret = lmb_reserve(&lmb, alloc_addr_b, 0x10000);
+	ut_asserteq(ret, 0);
+	ret = lmb_reserve(&lmb, alloc_addr_c, 0x10000);
+	ut_asserteq(ret, 0);
+	ASSERT_LMB(&lmb, ram, ram_size, 3, alloc_addr_a, 0x10000,
+		   alloc_addr_b, 0x10000, alloc_addr_c, 0x10000);
+
+	/* allocate blocks */
+	a = lmb_alloc_addr(&lmb, ram, alloc_addr_a - ram);
+	ut_asserteq(a, ram);
+	ASSERT_LMB(&lmb, ram, ram_size, 3, ram, 0x8010000,
+		   alloc_addr_b, 0x10000, alloc_addr_c, 0x10000);
+	b = lmb_alloc_addr(&lmb, alloc_addr_a + 0x10000,
+			   alloc_addr_b - alloc_addr_a - 0x10000);
+	ut_asserteq(b, alloc_addr_a + 0x10000);
+	ASSERT_LMB(&lmb, ram, ram_size, 2, ram, 0x10010000,
+		   alloc_addr_c, 0x10000, 0, 0);
+	c = lmb_alloc_addr(&lmb, alloc_addr_b + 0x10000,
+			   alloc_addr_c - alloc_addr_b - 0x10000);
+	ut_asserteq(c, alloc_addr_b + 0x10000);
+	ASSERT_LMB(&lmb, ram, ram_size, 1, ram, 0x18010000,
+		   0, 0, 0, 0);
+	d = lmb_alloc_addr(&lmb, alloc_addr_c + 0x10000,
+			   ram_end - alloc_addr_c - 0x10000);
+	ut_asserteq(d, alloc_addr_c + 0x10000);
+	ASSERT_LMB(&lmb, ram, ram_size, 1, ram, ram_size,
+		   0, 0, 0, 0);
+
+	/* allocating anything else should fail */
+	e = lmb_alloc(&lmb, 1, 1);
+	ut_asserteq(e, 0);
+	ASSERT_LMB(&lmb, ram, ram_size, 1, ram, ram_size,
+		   0, 0, 0, 0);
+
+	ret = lmb_free(&lmb, d, ram_end - alloc_addr_c - 0x10000);
+	ut_asserteq(ret, 0);
+
+	/* allocate at 3 points in free range */
+
+	d = lmb_alloc_addr(&lmb, ram_end - 4, 4);
+	ut_asserteq(d, ram_end - 4);
+	ASSERT_LMB(&lmb, ram, ram_size, 2, ram, 0x18010000,
+		   d, 4, 0, 0);
+	ret = lmb_free(&lmb, d, 4);
+	ut_asserteq(ret, 0);
+	ASSERT_LMB(&lmb, ram, ram_size, 1, ram, 0x18010000,
+		   0, 0, 0, 0);
+
+	d = lmb_alloc_addr(&lmb, ram_end - 128, 4);
+	ut_asserteq(d, ram_end - 128);
+	ASSERT_LMB(&lmb, ram, ram_size, 2, ram, 0x18010000,
+		   d, 4, 0, 0);
+	ret = lmb_free(&lmb, d, 4);
+	ut_asserteq(ret, 0);
+	ASSERT_LMB(&lmb, ram, ram_size, 1, ram, 0x18010000,
+		   0, 0, 0, 0);
+
+	d = lmb_alloc_addr(&lmb, alloc_addr_c + 0x10000, 4);
+	ut_asserteq(d, alloc_addr_c + 0x10000);
+	ASSERT_LMB(&lmb, ram, ram_size, 1, ram, 0x18010004,
+		   0, 0, 0, 0);
+	ret = lmb_free(&lmb, d, 4);
+	ut_asserteq(ret, 0);
+	ASSERT_LMB(&lmb, ram, ram_size, 1, ram, 0x18010000,
+		   0, 0, 0, 0);
+
+	/* allocate at the bottom */
+	ret = lmb_free(&lmb, a, alloc_addr_a - ram);
+	ut_asserteq(ret, 0);
+	ASSERT_LMB(&lmb, ram, ram_size, 1, ram + 0x8000000, 0x10010000,
+		   0, 0, 0, 0);
+	d = lmb_alloc_addr(&lmb, ram, 4);
+	ut_asserteq(d, ram);
+	ASSERT_LMB(&lmb, ram, ram_size, 2, d, 4,
+		   ram + 0x8000000, 0x10010000, 0, 0);
+
+	/* check that allocating outside memory fails */
+	if (ram_end != 0) {
+		ret = lmb_alloc_addr(&lmb, ram_end, 1);
+		ut_asserteq(ret, 0);
+	}
+	if (ram != 0) {
+		ret = lmb_alloc_addr(&lmb, ram - 1, 1);
+		ut_asserteq(ret, 0);
+	}
+
+	return 0;
+}
+
+static int lib_test_lmb_alloc_addr(struct unit_test_state *uts)
+{
+	int ret;
+
+	/* simulate 512 MiB RAM beginning at 1GiB */
+	ret = test_alloc_addr(uts, 0x40000000);
+	if (ret)
+		return ret;
+
+	/* simulate 512 MiB RAM beginning at 1.5GiB */
+	return test_alloc_addr(uts, 0xE0000000);
+}
+
+DM_TEST(lib_test_lmb_alloc_addr, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT);
+
+/* Simulate 512 MiB RAM, reserve 3 blocks, check addresses in between */
+static int test_get_unreserved_size(struct unit_test_state *uts,
+				    const phys_addr_t ram)
+{
+	const phys_size_t ram_size = 0x20000000;
+	const phys_addr_t ram_end = ram + ram_size;
+	const phys_size_t alloc_addr_a = ram + 0x8000000;
+	const phys_size_t alloc_addr_b = ram + 0x8000000 * 2;
+	const phys_size_t alloc_addr_c = ram + 0x8000000 * 3;
+	struct lmb lmb;
+	long ret;
+	phys_size_t s;
+
+	/* check for overflow */
+	ut_assert(ram_end == 0 || ram_end > ram);
+
+	lmb_init(&lmb);
+
+	ret = lmb_add(&lmb, ram, ram_size);
+	ut_asserteq(ret, 0);
+
+	/*  reserve 3 blocks */
+	ret = lmb_reserve(&lmb, alloc_addr_a, 0x10000);
+	ut_asserteq(ret, 0);
+	ret = lmb_reserve(&lmb, alloc_addr_b, 0x10000);
+	ut_asserteq(ret, 0);
+	ret = lmb_reserve(&lmb, alloc_addr_c, 0x10000);
+	ut_asserteq(ret, 0);
+	ASSERT_LMB(&lmb, ram, ram_size, 3, alloc_addr_a, 0x10000,
+		   alloc_addr_b, 0x10000, alloc_addr_c, 0x10000);
+
+	/* check addresses in between blocks */
+	s = lmb_get_unreserved_size(&lmb, ram);
+	ut_asserteq(s, alloc_addr_a - ram);
+	s = lmb_get_unreserved_size(&lmb, ram + 0x10000);
+	ut_asserteq(s, alloc_addr_a - ram - 0x10000);
+	s = lmb_get_unreserved_size(&lmb, alloc_addr_a - 4);
+	ut_asserteq(s, 4);
+
+	s = lmb_get_unreserved_size(&lmb, alloc_addr_a + 0x10000);
+	ut_asserteq(s, alloc_addr_b - alloc_addr_a - 0x10000);
+	s = lmb_get_unreserved_size(&lmb, alloc_addr_a + 0x20000);
+	ut_asserteq(s, alloc_addr_b - alloc_addr_a - 0x20000);
+	s = lmb_get_unreserved_size(&lmb, alloc_addr_b - 4);
+	ut_asserteq(s, 4);
+
+	s = lmb_get_unreserved_size(&lmb, alloc_addr_c + 0x10000);
+	ut_asserteq(s, ram_end - alloc_addr_c - 0x10000);
+	s = lmb_get_unreserved_size(&lmb, alloc_addr_c + 0x20000);
+	ut_asserteq(s, ram_end - alloc_addr_c - 0x20000);
+	s = lmb_get_unreserved_size(&lmb, ram_end - 4);
+	ut_asserteq(s, 4);
+
+	return 0;
+}
+
+static int lib_test_lmb_get_unreserved_size(struct unit_test_state *uts)
+{
+	int ret;
+
+	/* simulate 512 MiB RAM beginning at 1GiB */
+	ret = test_get_unreserved_size(uts, 0x40000000);
+	if (ret)
+		return ret;
+
+	/* simulate 512 MiB RAM beginning at 1.5GiB */
+	return test_get_unreserved_size(uts, 0xE0000000);
+}
+
+DM_TEST(lib_test_lmb_get_unreserved_size,
+	DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT);