From 471b5e42cc7d76678314542d0ce079e5f3cfb706 Mon Sep 17 00:00:00 2001 From: Chris Brandt Date: Thu, 16 Feb 2017 18:53:29 +0100 Subject: ARM: 8659/1: l2c: allow CA9 optimizations to be disabled If a PL310 is added to a system, but the sideband signals are not connected, some Cortex A9 optimizations cannot be used. In particular, enabling Full Line of Zeros in the CA9 without sidebands connected will crash the system since the CA9 will expect the L2C to perform operations, yet the L2C never gets the commands. Early BRESP also does not work without sideband signals. Signed-off-by: Chris Brandt Signed-off-by: Russell King --- arch/arm/mm/cache-l2x0.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) (limited to 'arch/arm/mm') diff --git a/arch/arm/mm/cache-l2x0.c b/arch/arm/mm/cache-l2x0.c index 2290be390f87..808efbb89b88 100644 --- a/arch/arm/mm/cache-l2x0.c +++ b/arch/arm/mm/cache-l2x0.c @@ -57,6 +57,9 @@ static unsigned long sync_reg_offset = L2X0_CACHE_SYNC; struct l2x0_regs l2x0_saved_regs; +static bool l2x0_bresp_disable; +static bool l2x0_flz_disable; + /* * Common code for all cache controllers. */ @@ -620,7 +623,7 @@ static void __init l2c310_enable(void __iomem *base, unsigned num_lock) u32 aux = l2x0_saved_regs.aux_ctrl; if (rev >= L310_CACHE_ID_RTL_R2P0) { - if (cortex_a9) { + if (cortex_a9 && !l2x0_bresp_disable) { aux |= L310_AUX_CTRL_EARLY_BRESP; pr_info("L2C-310 enabling early BRESP for Cortex-A9\n"); } else if (aux & L310_AUX_CTRL_EARLY_BRESP) { @@ -629,7 +632,7 @@ static void __init l2c310_enable(void __iomem *base, unsigned num_lock) } } - if (cortex_a9) { + if (cortex_a9 && !l2x0_flz_disable) { u32 aux_cur = readl_relaxed(base + L2X0_AUX_CTRL); u32 acr = get_auxcr(); @@ -1200,6 +1203,12 @@ static void __init l2c310_of_parse(const struct device_node *np, *aux_mask &= ~L2C_AUX_CTRL_PARITY_ENABLE; } + if (of_property_read_bool(np, "arm,early-bresp-disable")) + l2x0_bresp_disable = true; + + if (of_property_read_bool(np, "arm,full-line-zero-disable")) + l2x0_flz_disable = true; + prefetch = l2x0_saved_regs.prefetch_ctrl; ret = of_property_read_u32(np, "arm,double-linefill", &val); -- cgit