Commit bee91c3a authored by Eugeniy Paltsev's avatar Eugeniy Paltsev Committed by Vineet Gupta
Browse files

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: default avatarEugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: default avatarVineet Gupta <vgupta@synopsys.com>
[vgupta: reworked the changelog]
parent 0fa400cb

arch/arc/mm/cache.c

+19 −8
Original line number Diff line number Diff line
@@ -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);

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