From bee91c3a3ce63daf64bb53ae60e6a2fb2961d3d7 Mon Sep 17 00:00:00 2001 From: Eugeniy Paltsev Date: Tue, 15 Aug 2017 21:13:53 +0300 Subject: 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 Signed-off-by: Vineet Gupta [vgupta: reworked the changelog] --- arch/arc/mm/cache.c | 27 +++++++++++++++++++-------- 1 file changed, 19 insertions(+), 8 deletions(-) (limited to 'arch/arc') 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); -- cgit