From a7c535e3a8e50e625750d2aa0ed4f84591ca7bfa Mon Sep 17 00:00:00 2001 From: Juergen Borleis Date: Mon, 27 Apr 2015 15:59:50 +0200 Subject: [PATCH] rtc: imxdi: monitor a security violation at runtime Maybe the unit enters the hardware related state at runtime and not at system boot time (after a power cycle). Signed-off-by: Juergen Borleis Signed-off-by: Robert Schwebel [rsc: got NDA clearance from Freescale] Signed-off-by: Alexandre Belloni --- drivers/rtc/rtc-imxdi.c | 21 +++++++++++++++++++-- 1 file changed, 19 insertions(+), 2 deletions(-) diff --git a/drivers/rtc/rtc-imxdi.c b/drivers/rtc/rtc-imxdi.c index 3d7f0390170e..a08da4a353db 100644 --- a/drivers/rtc/rtc-imxdi.c +++ b/drivers/rtc/rtc-imxdi.c @@ -665,6 +665,25 @@ static irqreturn_t dryice_norm_irq(int irq, void *dev_id) irqreturn_t rc = IRQ_NONE; dier = readl(imxdi->ioaddr + DIER); + dsr = readl(imxdi->ioaddr + DSR); + + /* handle the security violation event */ + if (dier & DIER_SVIE) { + if (dsr & DSR_SVF) { + /* + * Disable the interrupt when this kind of event has + * happened. + * There cannot be more than one event of this type, + * because it needs a complex state change + * including a main power cycle to get again out of + * this state. + */ + di_int_disable(imxdi, DIER_SVIE); + /* report the violation */ + di_report_tamper_info(imxdi, dsr); + rc = IRQ_HANDLED; + } + } /* handle write complete and write error cases */ if (dier & DIER_WCIE) { @@ -675,7 +694,6 @@ static irqreturn_t dryice_norm_irq(int irq, void *dev_id) return rc; /* DSR_WCF clears itself on DSR read */ - dsr = readl(imxdi->ioaddr + DSR); if (dsr & (DSR_WCF | DSR_WEF)) { /* mask the interrupt */ di_int_disable(imxdi, DIER_WCIE); @@ -691,7 +709,6 @@ static irqreturn_t dryice_norm_irq(int irq, void *dev_id) /* handle the alarm case */ if (dier & DIER_CAIE) { /* DSR_WCF clears itself on DSR read */ - dsr = readl(imxdi->ioaddr + DSR); if (dsr & DSR_CAF) { /* mask the interrupt */ di_int_disable(imxdi, DIER_CAIE); -- 2.20.1