[PATCH 10/14] clock-snapdragon: Add clk_rcg_set_rate() with mnd_width=0

[Sumit Garg]

Add clk_rcg_set_rate() which allows to configure clocks without programming
MND values. This is required for configuring I2C clocks on QCS404.

Co-developed-by: Mike Worsfold <mworsfold at impinj.com>
Signed-off-by: Mike Worsfold <mworsfold at impinj.com>
Signed-off-by: Sumit Garg <sumit.garg at linaro.org>
---
 arch/arm/mach-snapdragon/clock-snapdragon.c | 24 +++++++++++++++++++++
 arch/arm/mach-snapdragon/clock-snapdragon.h |  2 ++
 2 files changed, 26 insertions(+)

diff --git a/arch/arm/mach-snapdragon/clock-snapdragon.c b/arch/arm/mach-snapdragon/clock-snapdragon.c
index fda7098274..0ac45dce9a 100644
--- a/arch/arm/mach-snapdragon/clock-snapdragon.c
+++ b/arch/arm/mach-snapdragon/clock-snapdragon.c
@@ -111,6 +111,30 @@ void clk_rcg_set_rate_mnd(phys_addr_t base, const struct bcr_regs *regs,
 	clk_bcr_update(base + regs->cmd_rcgr);
 }
 
+/* root set rate for clocks with half integer and mnd_width=0 */
+void clk_rcg_set_rate(phys_addr_t base, const struct bcr_regs *regs, int div,
+		      int source)
+{
+	u32 cfg;
+
+	/* setup src select and divider */
+	cfg  = readl(base + regs->cfg_rcgr);
+	cfg &= ~CFG_MASK;
+	cfg |= source & CFG_CLK_SRC_MASK; /* Select clock source */
+
+	/*
+	 * Set the divider; HW permits fraction dividers (+0.5), but
+	 * for simplicity, we will support integers only
+	 */
+	if (div)
+		cfg |= (2 * div - 1) & CFG_DIVIDER_MASK;
+
+	writel(cfg, base + regs->cfg_rcgr); /* Write new clock configuration */
+
+	/* Inform h/w to start using the new config. */
+	clk_bcr_update(base + regs->cmd_rcgr);
+}
+
 static int msm_clk_probe(struct udevice *dev)
 {
 	struct msm_clk_priv *priv = dev_get_priv(dev);
diff --git a/arch/arm/mach-snapdragon/clock-snapdragon.h b/arch/arm/mach-snapdragon/clock-snapdragon.h
index 2ac53b538d..c90bbefa58 100644
--- a/arch/arm/mach-snapdragon/clock-snapdragon.h
+++ b/arch/arm/mach-snapdragon/clock-snapdragon.h
@@ -42,5 +42,7 @@ void clk_enable_cbc(phys_addr_t cbcr);
 void clk_enable_vote_clk(phys_addr_t base, const struct vote_clk *vclk);
 void clk_rcg_set_rate_mnd(phys_addr_t base, const struct bcr_regs *regs,
 			  int div, int m, int n, int source);
+void clk_rcg_set_rate(phys_addr_t base, const struct bcr_regs *regs, int div,
+		      int source);
 
 #endif
-- 
2.34.1