ARM: OMAP2+: Detect incorrectly aligned GPMC base address

Each GPMC chip-select can be configured to map 16MB, 32MB, 64MB or 128MB
of address space. The physical base address where a chip-select starts
is also configurable and must be aligned on a boundary that is equal to
or greater than the size of the address space mapped bt the chip-select.
When enabling a GPMC chip-select, ensure that the base address is aligned
to the appropriate boundary.

Reported-by: Mark Jackson <mpfj-list@mimc.co.uk>
Signed-off-by: Jon Hunter <jon-hunter@ti.com>
Tested-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>

diff --git a/arch/arm/mach-omap2/gpmc.c b/arch/arm/mach-omap2/gpmc.c
index c7bf6dd..5c22b5a 100644 (file)
--- a/arch/arm/mach-omap2/gpmc.c
+++ b/arch/arm/mach-omap2/gpmc.c
@@ -403,11 +403,18 @@ int gpmc_cs_set_timings(int cs, const struct gpmc_timings *t)
        return 0;
 }
 
-static void gpmc_cs_enable_mem(int cs, u32 base, u32 size)
+static int gpmc_cs_enable_mem(int cs, u32 base, u32 size)
 {
        u32 l;
        u32 mask;
 
+       /*
+        * Ensure that base address is aligned on a
+        * boundary equal to or greater than size.
+        */
+       if (base & (size - 1))
+               return -EINVAL;
+
        mask = (1 << GPMC_SECTION_SHIFT) - size;
        l = gpmc_cs_read_reg(cs, GPMC_CS_CONFIG7);
        l &= ~0x3f;
@@ -416,6 +423,8 @@ static void gpmc_cs_enable_mem(int cs, u32 base, u32 size)
        l |= ((mask >> GPMC_CHUNK_SHIFT) & 0x0f) << 8;
        l |= GPMC_CONFIG7_CSVALID;
        gpmc_cs_write_reg(cs, GPMC_CS_CONFIG7, l);
+
+       return 0;
 }
 
 static void gpmc_cs_disable_mem(int cs)
@@ -526,7 +535,9 @@ static int gpmc_cs_remap(int cs, u32 base)
        ret = gpmc_cs_insert_mem(cs, base, size);
        if (ret < 0)
                return ret;
-       gpmc_cs_enable_mem(cs, base, size);
+       ret = gpmc_cs_enable_mem(cs, base, size);
+       if (ret < 0)
+               return ret;
 
        return 0;
 }
@@ -556,7 +567,12 @@ int gpmc_cs_request(int cs, unsigned long size, unsigned long *base)
        if (r < 0)
                goto out;
 
-       gpmc_cs_enable_mem(cs, res->start, resource_size(res));
+       r = gpmc_cs_enable_mem(cs, res->start, resource_size(res));
+       if (r < 0) {
+               release_resource(res);
+               goto out;
+       }
+
        *base = res->start;
        gpmc_cs_set_reserved(cs, 1);
 out: