Commit 3af5a67c authored Feb 08, 2016 by Paul Burton Committed by Ralf Baechle Feb 09, 2016

MIPS: Fix early CM probing



Commit c014d164 ("MIPS: Add platform callback before initializing
the L2 cache") added a platform_early_l2_init function in order to allow
platforms to probe for the CM before L2 initialisation is performed, so
that CM GCRs are available to mips_sc_probe.

That commit actually fails to do anything useful, since it checks
mips_cm_revision to determine whether it should call mips_cm_probe but
the result of mips_cm_revision will always be 0 until mips_cm_probe has
been called. Thus the "early" mips_cm_probe call never occurs.

Fix this & drop the useless weak platform_early_l2_init function by
simply calling mips_cm_probe from setup_arch. For platforms that don't
select CONFIG_MIPS_CM this will be a no-op, and for those that do it
removes the requirement for them to call mips_cm_probe manually
(although doing so isn't harmful for now).

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Reviewed-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Cc: Andrzej Hajda <a.hajda@samsung.com>
Cc: Aaro Koskinen <aaro.koskinen@nokia.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Rob Herring <robh@kernel.org>
Cc: Peter Hurley <peter@hurleysoftware.com>
Cc: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Cc: Jaedon Shin <jaedon.shin@gmail.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Jonas Gorski <jogo@openwrt.org>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12475/


Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

parent e6c058f9

arch/mips/kernel/setup.c

+1 −0

Original line number	Diff line number	Diff line
		@@ -782,6 +782,7 @@ static inline void prefill_possible_map(void) {}
		void __init setup_arch(char **cmdline_p)
		{
		cpu_probe();
		mips_cm_probe();
		prom_init();

		setup_early_fdc_console();

arch/mips/mm/sc-mips.c

+0 −10

Original line number	Diff line number	Diff line
		@@ -181,10 +181,6 @@ static int __init mips_sc_probe_cm3(void)
		return 1;
		}

		void __weak platform_early_l2_init(void)
		{
		}

		static inline int __init mips_sc_probe(void)
		{
		struct cpuinfo_mips *c = &current_cpu_data;
		@@ -194,12 +190,6 @@ static inline int __init mips_sc_probe(void)
		/* Mark as not present until probe completed */
		c->scache.flags \|= MIPS_CACHE_NOT_PRESENT;

		/*
		* Do we need some platform specific probing before
		* we configure L2?
		*/
		platform_early_l2_init();

		if (mips_cm_revision() >= CM_REV_CM3)
		return mips_sc_probe_cm3();

arch/mips/mti-malta/malta-init.c

+0 −8

Original line number	Diff line number	Diff line
		@@ -293,7 +293,6 @@ void __init prom_init(void)
		console_config();
		#endif
		/* Early detection of CMP support */
		mips_cm_probe();
		mips_cpc_probe();

		if (!register_cps_smp_ops())
		@@ -304,10 +303,3 @@ void __init prom_init(void)
		return;
		register_up_smp_ops();
		}

		void platform_early_l2_init(void)
		{
		/* L2 configuration lives in the CM3 */
		if (mips_cm_revision() >= CM_REV_CM3)
		mips_cm_probe();
		}