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authorEugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>2017-08-15 21:13:53 +0300
committerVineet Gupta <vgupta@synopsys.com>2017-09-01 21:26:26 +0300
commitbee91c3a3ce63daf64bb53ae60e6a2fb2961d3d7 (patch)
tree06d55b2574b1eebbdd5e12e4a56da04f9a9e9806 /arch/arc
parent0fa400cb8a90753044bbcb5810fa1a59d96d5ea1 (diff)
downloadlinux-bee91c3a3ce63daf64bb53ae60e6a2fb2961d3d7.tar.xz
ARCv2: IOC: Tighten up the contraints (specifically base / size alignment)
[Needed for HSDK] - Currently IOC base is hardcoded to 0x8000_0000 which is default value of LINUX_LINK_BASE, but may not always be the case - IOC programming model imposes the constraint that IOC aperture size needs to be aligned to IOC base address, which we were not checking so far. Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com> [vgupta: reworked the changelog]
Diffstat (limited to 'arch/arc')
-rw-r--r--arch/arc/mm/cache.c27
1 files changed, 19 insertions, 8 deletions
diff --git a/arch/arc/mm/cache.c b/arch/arc/mm/cache.c
index ad498e58a1fe..d68d36c15909 100644
--- a/arch/arc/mm/cache.c
+++ b/arch/arc/mm/cache.c
@@ -1147,7 +1147,7 @@ SYSCALL_DEFINE3(cacheflush, uint32_t, start, uint32_t, sz, uint32_t, flags)
*/
noinline void __init arc_ioc_setup(void)
{
- unsigned int ap_sz;
+ unsigned int ioc_base, mem_sz;
/* Flush + invalidate + disable L1 dcache */
__dc_disable();
@@ -1156,18 +1156,29 @@ noinline void __init arc_ioc_setup(void)
if (read_aux_reg(ARC_REG_SLC_BCR))
slc_entire_op(OP_FLUSH_N_INV);
- /* IOC Aperture start: TDB: handle non default CONFIG_LINUX_LINK_BASE */
- write_aux_reg(ARC_REG_IO_COH_AP0_BASE, 0x80000);
-
/*
- * IOC Aperture size:
- * decoded as 2 ^ (SIZE + 2) KB: so setting 0x11 implies 512M
+ * currently IOC Aperture covers entire DDR
* TBD: fix for PGU + 1GB of low mem
* TBD: fix for PAE
*/
- ap_sz = order_base_2(arc_get_mem_sz()/1024) - 2;
- write_aux_reg(ARC_REG_IO_COH_AP0_SIZE, ap_sz);
+ mem_sz = arc_get_mem_sz();
+
+ if (!is_power_of_2(mem_sz) || mem_sz < 4096)
+ panic("IOC Aperture size must be power of 2 larger than 4KB");
+
+ /*
+ * IOC Aperture size decoded as 2 ^ (SIZE + 2) KB,
+ * so setting 0x11 implies 512MB, 0x12 implies 1GB...
+ */
+ write_aux_reg(ARC_REG_IO_COH_AP0_SIZE, order_base_2(mem_sz >> 10) - 2);
+
+ /* for now assume kernel base is start of IOC aperture */
+ ioc_base = CONFIG_LINUX_LINK_BASE;
+
+ if (ioc_base % mem_sz != 0)
+ panic("IOC Aperture start must be aligned to the size of the aperture");
+ write_aux_reg(ARC_REG_IO_COH_AP0_BASE, ioc_base >> 12);
write_aux_reg(ARC_REG_IO_COH_PARTIAL, 1);
write_aux_reg(ARC_REG_IO_COH_ENABLE, 1);