Merge tag 'socfpga-clk-update-for-v3.16' of git://git.rocketboards.org/linux-socfpga-next into clk-next-socfpga

Adds support getting the divider registers for the MAIN PLL that was once
thought to be hidden.

3 files changed, 23 insertions, 4 deletions

diff --git a/drivers/clk/socfpga/clk-gate.c b/drivers/clk/socfpga/clk-gate.c
index 501d513bf890..dd3a78c64795 100644
--- a/drivers/clk/socfpga/clk-gate.c
+++ b/drivers/clk/socfpga/clk-gate.c
@@ -32,7 +32,6 @@
 #define SOCFPGA_MMC_CLK			"sdmmc_clk"
 #define SOCFPGA_GPIO_DB_CLK_OFFSET	0xA8
 
-#define div_mask(width)	((1 << (width)) - 1)
 #define streq(a, b) (strcmp((a), (b)) == 0)
 
 #define to_socfpga_gate_clk(p) container_of(p, struct socfpga_gate_clk, hw.hw)
diff --git a/drivers/clk/socfpga/clk-periph.c b/drivers/clk/socfpga/clk-periph.c
index 81623a3736f9..46531c34ec9b 100644
--- a/drivers/clk/socfpga/clk-periph.c
+++ b/drivers/clk/socfpga/clk-periph.c
@@ -29,12 +29,18 @@ static unsigned long clk_periclk_recalc_rate(struct clk_hw *hwclk,
 					     unsigned long parent_rate)
 {
 	struct socfpga_periph_clk *socfpgaclk = to_socfpga_periph_clk(hwclk);
-	u32 div;
+	u32 div, val;
 
-	if (socfpgaclk->fixed_div)
+	if (socfpgaclk->fixed_div) {
 		div = socfpgaclk->fixed_div;
-	else
+	} else {
+		if (socfpgaclk->div_reg) {
+			val = readl(socfpgaclk->div_reg) >> socfpgaclk->shift;
+			val &= div_mask(socfpgaclk->width);
+			parent_rate /= (val + 1);
+		}
 		div = ((readl(socfpgaclk->hw.reg) & 0x1ff) + 1);
+	}
 
 	return parent_rate / div;
 }
@@ -54,6 +60,7 @@ static __init void __socfpga_periph_init(struct device_node *node,
 	struct clk_init_data init;
 	int rc;
 	u32 fixed_div;
+	u32 div_reg[3];
 
 	of_property_read_u32(node, "reg", &reg);
 
@@ -63,6 +70,15 @@ static __init void __socfpga_periph_init(struct device_node *node,
 
 	periph_clk->hw.reg = clk_mgr_base_addr + reg;
 
+	rc = of_property_read_u32_array(node, "div-reg", div_reg, 3);
+	if (!rc) {
+		periph_clk->div_reg = clk_mgr_base_addr + div_reg[0];
+		periph_clk->shift = div_reg[1];
+		periph_clk->width = div_reg[2];
+	} else {
+		periph_clk->div_reg = 0;
+	}
+
 	rc = of_property_read_u32(node, "fixed-divider", &fixed_div);
 	if (rc)
 		periph_clk->fixed_div = 0;
diff --git a/drivers/clk/socfpga/clk.h b/drivers/clk/socfpga/clk.h
index d2e54019c94f..d291f60c46e1 100644
--- a/drivers/clk/socfpga/clk.h
+++ b/drivers/clk/socfpga/clk.h
@@ -27,6 +27,7 @@
 #define CLKMGR_PERPLL_SRC	0xAC
 
 #define SOCFPGA_MAX_PARENTS		3
+#define div_mask(width) ((1 << (width)) - 1)
 
 extern void __iomem *clk_mgr_base_addr;
 
@@ -52,6 +53,9 @@ struct socfpga_periph_clk {
 	struct clk_gate hw;
 	char *parent_name;
 	u32 fixed_div;
+	void __iomem *div_reg;
+	u32 width;      /* only valid if div_reg != 0 */
+	u32 shift;      /* only valid if div_reg != 0 */
 };
 
 #endif /* SOCFPGA_CLK_H */