sunxi_nand_spl: Turn off clocks when we're done with the nand

Turn off the nand and dma clocks when we're done with the nand, this
puts the nand and dma controllers back into a clean state for when the
kernel boots.

Without this the kernel will not boot properly when it is built with
dma-controller support.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Ian Campbell <ijc@hellion.org.uk>

drivers/mtd/nand/sunxi_nand_spl.c

@@ -5,9 +5,10 @@
  * SPDX-License-Identifier:     GPL-2.0+
  */
 
+#include <asm/arch/clock.h>
+#include <asm/io.h>
 #include <common.h>
 #include <config.h>
-#include <asm/io.h>
 #include <nand.h>
 
 /* registers */
@@ -330,4 +331,16 @@ int nand_spl_load_image(uint32_t offs, unsigned int size, void *dest)
 	return ecc_errors ? -1 : 0;
 }
 
-void nand_deselect(void) {}
+void nand_deselect(void)
+{
+	struct sunxi_ccm_reg *const ccm =
+		(struct sunxi_ccm_reg *)SUNXI_CCM_BASE;
+
+	clrbits_le32(&ccm->ahb_gate0, (CLK_GATE_OPEN << AHB_GATE_OFFSET_NAND0));
+#ifdef CONFIG_MACH_SUN9I
+	clrbits_le32(&ccm->ahb_gate1, (1 << AHB_GATE_OFFSET_DMA));
+#else
+	clrbits_le32(&ccm->ahb_gate0, (1 << AHB_GATE_OFFSET_DMA));
+#endif
+	clrbits_le32(&ccm->nand0_clk_cfg, CCM_NAND_CTRL_ENABLE | AHB_DIV_1);
+}