Merge "ARM: hw_breakpoint: don't clear bkpts during halting mode debug" (6675d9b6) · Commits · e / devices / android_kernel_oneplus_sm8150

arch/arm/kernel/hw_breakpoint.c

+23 −0

Original line number	Diff line number	Diff line
		@@ -226,6 +226,18 @@ static int get_num_brps(void)
		return core_has_mismatch_brps() ? brps - 1 : brps;
		}

		/* Determine if halting mode is enabled */
		static int halting_mode_enabled(void)
		{
		u32 dscr;

		ARM_DBG_READ(c0, c1, 0, dscr);
		WARN_ONCE(dscr & ARM_DSCR_HDBGEN,
		"halting debug mode enabled. Unable to access hardware resources.\n");

		return !!(dscr & ARM_DSCR_HDBGEN);
		}

		/*
		* In order to access the breakpoint/watchpoint control registers,
		* we must be running in debug monitor mode. Unfortunately, we can
		@@ -930,6 +942,17 @@ static void reset_ctrl_regs(unsigned int cpu)
		int i, raw_num_brps, err = 0;
		u32 val;

		/*
		* Bail out without clearing the breakpoint registers if halting
		* debug mode or monitor debug mode is enabled. Checking for monitor
		* debug mode here ensures we don't clear the breakpoint registers
		* across power collapse if save and restore code has already
		* preserved the debug register values or they weren't lost and
		* monitor mode was already enabled earlier.
		*/
		if (halting_mode_enabled() \|\| monitor_mode_enabled())
		return;

		/*
		* v7 debug contains save and restore registers so that debug state
		* can be maintained across low-power modes without leaving the debug