sunxi: Support H3 CCU security switches

H3's CCU includes some switches which disable non-secure access to some
of the more critical clock controls, such as MBUS, PLLs, and main
platform busses.

Configure them to enable non-secure access.

For now the only SoC that has this feature is the H3. For other
platforms just use a default (weak) empty function so things do
not break.

Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Acked-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

arch/arm/cpu/armv7/sunxi/clock.c

@@ -14,12 +14,17 @@
 #include <asm/arch/gpio.h>
 #include <asm/arch/sys_proto.h>
 
+__weak void clock_init_sec(void)
+{
+}
+
 int clock_init(void)
 {
 #ifdef CONFIG_SPL_BUILD
 	clock_init_safe();
 #endif
 	clock_init_uart();
+	clock_init_sec();
 
 	return 0;
 }

arch/arm/cpu/armv7/sunxi/clock_sun6i.c

@@ -45,6 +45,19 @@ void clock_init_safe(void)
 }
 #endif
 
+void clock_init_sec(void)
+{
+#ifdef CONFIG_MACH_SUN8I_H3
+	struct sunxi_ccm_reg * const ccm =
+		(struct sunxi_ccm_reg *)SUNXI_CCM_BASE;
+
+	setbits_le32(&ccm->ccu_sec_switch,
+		     CCM_SEC_SWITCH_MBUS_NONSEC |
+		     CCM_SEC_SWITCH_BUS_NONSEC |
+		     CCM_SEC_SWITCH_PLL_NONSEC);
+#endif
+}
+
 void clock_init_uart(void)
 {
 #if CONFIG_CONS_INDEX < 5

arch/arm/include/asm/arch-sunxi/clock.h

@@ -30,6 +30,7 @@ int clock_init(void);
 int clock_twi_onoff(int port, int state);
 void clock_set_de_mod_clock(u32 *clk_cfg, unsigned int hz);
 void clock_init_safe(void);
+void clock_init_sec(void);
 void clock_init_uart(void);
 #endif
 

arch/arm/include/asm/arch-sunxi/clock_sun6i.h

@@ -137,6 +137,8 @@ struct sunxi_ccm_reg {
 	u32 apb1_reset_cfg;	/* 0x2d0 APB1 Reset config */
 	u32 reserved24;
 	u32 apb2_reset_cfg;	/* 0x2d8 APB2 Reset config */
+	u32 reserved25[5];
+	u32 ccu_sec_switch;	/* 0x2f0 CCU Security Switch, H3 only */
 };
 
 /* apb2 bit field */
@@ -375,6 +377,11 @@ struct sunxi_ccm_reg {
 #define CCM_DE_CTRL_PLL10		(5 << 24)
 #define CCM_DE_CTRL_GATE		(1 << 31)
 
+/* CCU security switch, H3 only */
+#define CCM_SEC_SWITCH_MBUS_NONSEC	(1 << 2)
+#define CCM_SEC_SWITCH_BUS_NONSEC	(1 << 1)
+#define CCM_SEC_SWITCH_PLL_NONSEC	(1 << 0)
+
 #ifndef __ASSEMBLY__
 void clock_set_pll1(unsigned int hz);
 void clock_set_pll3(unsigned int hz);