ARM: l2c: add warnings for stuff modifying aux_ctrl register values (560be613) · Commits · e / devices / android_kernel_oneplus_sm8150

arch/arm/mm/cache-l2x0.c

+22 −3

Original line number	Diff line number	Diff line
		@@ -755,13 +755,24 @@ static void __init __l2c_init(const struct l2c_init_data *data,
		{
		struct outer_cache_fns fns;
		unsigned way_size_bits, ways;
		u32 aux;
		u32 aux, old_aux;

		aux = readl_relaxed(l2x0_base + L2X0_AUX_CTRL);
		/*
		* Sanity check the aux values. aux_mask is the bits we preserve
		* from reading the hardware register, and aux_val is the bits we
		* set.
		*/
		if (aux_val & aux_mask)
		pr_alert("L2C: platform provided aux values permit register corruption.\n");

		old_aux = aux = readl_relaxed(l2x0_base + L2X0_AUX_CTRL);
		aux &= aux_mask;
		aux \|= aux_val;

		if (old_aux != aux)
		pr_warn("L2C: DT/platform modifies aux control register: 0x%08x -> 0x%08x\n",
		old_aux, aux);

		/* Determine the number of ways */
		switch (cache_id & L2X0_CACHE_ID_PART_MASK) {
		case L2X0_CACHE_ID_PART_L310:
		@@ -1392,7 +1403,7 @@ int __init l2x0_of_init(u32 aux_val, u32 aux_mask)
		const struct l2c_init_data *data;
		struct device_node *np;
		struct resource res;
		u32 cache_id;
		u32 cache_id, old_aux;

		np = of_find_matching_node(NULL, l2x0_ids);
		if (!np)
		@@ -1409,6 +1420,14 @@ int __init l2x0_of_init(u32 aux_val, u32 aux_mask)

		data = of_match_node(l2x0_ids, np)->data;

		old_aux = readl_relaxed(l2x0_base + L2X0_AUX_CTRL);
		if (old_aux != ((old_aux & aux_mask) \| aux_val)) {
		pr_warn("L2C: platform modifies aux control register: 0x%08x -> 0x%08x\n",
		old_aux, (old_aux & aux_mask) \| aux_val);
		} else if (aux_mask != ~0U && aux_val != 0) {
		pr_alert("L2C: platform provided aux values match the hardware, so have no effect. Please remove them.\n");
		}

		/* All L2 caches are unified, so this property should be specified */
		if (!of_property_read_bool(np, "cache-unified"))
		pr_err("L2C: device tree omits to specify unified cache\n");