From 05b2de7d0861b0bc6013ccaec021c07f068cb501 Mon Sep 17 00:00:00 2001 From: Dmitry Osipenko Date: Mon, 27 May 2019 20:21:46 +0800 Subject: [PATCH] memory: tegra: Fix integer overflow on tick value calculation commit b906c056b6023c390f18347169071193fda57dde upstream. Multiplying the Memory Controller clock rate by the tick count results in an integer overflow and in result the truncated tick value is being programmed into hardware, such that the GR3D memory client performance is reduced by two times. Cc: stable Signed-off-by: Dmitry Osipenko Signed-off-by: Thierry Reding Signed-off-by: Greg Kroah-Hartman Signed-off-by: Yang Yingliang --- drivers/memory/tegra/mc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/memory/tegra/mc.c b/drivers/memory/tegra/mc.c index bd25faf6d13d..c8f16666256c 100644 --- a/drivers/memory/tegra/mc.c +++ b/drivers/memory/tegra/mc.c @@ -280,7 +280,7 @@ static int tegra_mc_setup_latency_allowance(struct tegra_mc *mc) u32 value; /* compute the number of MC clock cycles per tick */ - tick = mc->tick * clk_get_rate(mc->clk); + tick = (unsigned long long)mc->tick * clk_get_rate(mc->clk); do_div(tick, NSEC_PER_SEC); value = readl(mc->regs + MC_EMEM_ARB_CFG); -- GitLab