@@ -713,14 +713,32 @@ static void gpmi_nfc_compute_timings(str
(use_half_period ? BM_GPMI_CTRL1_HALF_PERIOD : 0);
}
-static void gpmi_nfc_apply_timings(struct gpmi_nand_data *this)
+static int gpmi_nfc_apply_timings(struct gpmi_nand_data *this)
{
struct gpmi_nfc_hardware_timing *hw = &this->hw;
struct resources *r = &this->resources;
void __iomem *gpmi_regs = r->gpmi_regs;
unsigned int dll_wait_time_us;
+ int ret;
+
+ /* Clock dividers do NOT guarantee a clean clock signal on its output
+ * during the change of the divide factor on i.MX6Q/UL/SX. On i.MX7/8,
+ * all clock dividers provide these guarantee.
+ */
+ if (GPMI_IS_MX6Q(this) || GPMI_IS_MX6SX(this))
+ clk_disable_unprepare(r->clock[0]);
+
+ ret = clk_set_rate(r->clock[0], hw->clk_rate);
+ if (ret) {
+ dev_err(this->dev, "cannot set clock rate to %lu Hz: %d\n", hw->clk_rate, ret);
+ return ret;
+ }
- clk_set_rate(r->clock[0], hw->clk_rate);
+ if (GPMI_IS_MX6Q(this) || GPMI_IS_MX6SX(this)) {
+ ret = clk_prepare_enable(r->clock[0]);
+ if (ret)
+ return ret;
+ }
writel(hw->timing0, gpmi_regs + HW_GPMI_TIMING0);
writel(hw->timing1, gpmi_regs + HW_GPMI_TIMING1);
@@ -739,6 +757,8 @@ static void gpmi_nfc_apply_timings(struc
/* Wait for the DLL to settle. */
udelay(dll_wait_time_us);
+
+ return 0;
}
static int gpmi_setup_interface(struct nand_chip *chip, int chipnr,
@@ -2278,7 +2298,9 @@ static int gpmi_nfc_exec_op(struct nand_
*/
if (this->hw.must_apply_timings) {
this->hw.must_apply_timings = false;
- gpmi_nfc_apply_timings(this);
+ ret = gpmi_nfc_apply_timings(this);
+ if (ret)
+ return ret;
}
dev_dbg(this->dev, "%s: %d instructions\n", __func__, op->ninstrs);