[1/8] clk: tegra: Add PLLE HW power sequencer control
diff mbox series

Message ID 20190614074652.21960-2-jckuo@nvidia.com
State New
Headers show
Series
  • Tegra XHCI controller ELPG support
Related show

Commit Message

JC Kuo June 14, 2019, 7:46 a.m. UTC
PLLE hardware power sequencer has to be enabled after PEX/SATA
UPHY PLL's sequencers are enabled.

tegra210_plle_hw_sequence_start() for XUSB PADCTL driver to enable
PLLE hardware sequencer at proper time.

tegra210_plle_hw_sequence_is_enabled() for XUSB PADCTL driver to
check whether PLLE hardware sequencer has been enabled or not.

Signed-off-by: JC Kuo <jckuo@nvidia.com>
---
 drivers/clk/tegra/clk-tegra210.c | 45 ++++++++++++++++++++++++++++++++
 include/linux/clk/tegra.h        |  2 ++
 2 files changed, 47 insertions(+)

Comments

Jon Hunter July 4, 2019, 12:16 p.m. UTC | #1
On 14/06/2019 08:46, JC Kuo wrote:
> PLLE hardware power sequencer has to be enabled after PEX/SATA
> UPHY PLL's sequencers are enabled.
> 
> tegra210_plle_hw_sequence_start() for XUSB PADCTL driver to enable
> PLLE hardware sequencer at proper time.
> 
> tegra210_plle_hw_sequence_is_enabled() for XUSB PADCTL driver to
> check whether PLLE hardware sequencer has been enabled or not.

I think that here to be clear about what is going on you should state
that you are "adding the function tegra210_plle_hw_sequence_start() ..."

Are these functions dependent upon clk_plle_tegra210_enable() already
being called? I assume that there must be some dependency between the
above functions and the existing plle enable function. If there is a
dependency, how do you ensure the existing enable is already called?

Cheers
Jon

Patch
diff mbox series

diff --git a/drivers/clk/tegra/clk-tegra210.c b/drivers/clk/tegra/clk-tegra210.c
index e1ba62d2b1a0..14d330669f36 100644
--- a/drivers/clk/tegra/clk-tegra210.c
+++ b/drivers/clk/tegra/clk-tegra210.c
@@ -398,6 +398,14 @@  static const char *mux_pllmcp_clkm[] = {
 #define PLLRE_BASE_DEFAULT_MASK		0x1c000000
 #define PLLRE_MISC0_WRITE_MASK		0x67ffffff
 
+/* PLLE */
+#define PLLE_MISC_IDDQ_SW_CTRL		(1 << 14)
+#define PLLE_AUX_USE_LOCKDET		(1 << 3)
+#define PLLE_AUX_SS_SEQ_INCLUDE		(1 << 31)
+#define PLLE_AUX_ENABLE_SWCTL		(1 << 4)
+#define PLLE_AUX_SS_SWCTL		(1 << 6)
+#define PLLE_AUX_SEQ_ENABLE		(1 << 24)
+
 /* PLLX */
 #define PLLX_USE_DYN_RAMP		1
 #define PLLX_BASE_LOCK			(1 << 27)
@@ -484,6 +492,43 @@  static const char *mux_pllmcp_clkm[] = {
 #define PLLU_MISC0_WRITE_MASK		0xbfffffff
 #define PLLU_MISC1_WRITE_MASK		0x00000007
 
+bool tegra210_plle_hw_sequence_is_enabled(void)
+{
+	u32 val;
+
+	val = readl_relaxed(clk_base + PLLE_AUX);
+	if (val & PLLE_AUX_SEQ_ENABLE)
+		return true;
+
+	return false;
+}
+EXPORT_SYMBOL_GPL(tegra210_plle_hw_sequence_is_enabled);
+
+void tegra210_plle_hw_sequence_start(void)
+{
+	u32 val;
+
+	if (tegra210_plle_hw_sequence_is_enabled())
+		return;
+
+	val = readl_relaxed(clk_base + PLLE_MISC0);
+	val &= ~PLLE_MISC_IDDQ_SW_CTRL;
+	writel_relaxed(val, clk_base + PLLE_MISC0);
+
+	val = readl_relaxed(clk_base + PLLE_AUX);
+	val |= (PLLE_AUX_USE_LOCKDET | PLLE_AUX_SS_SEQ_INCLUDE);
+	val &= ~(PLLE_AUX_ENABLE_SWCTL | PLLE_AUX_SS_SWCTL);
+	writel_relaxed(val, clk_base + PLLE_AUX);
+
+	fence_udelay(1, clk_base);
+
+	val |= PLLE_AUX_SEQ_ENABLE;
+	writel_relaxed(val, clk_base + PLLE_AUX);
+
+	fence_udelay(1, clk_base);
+}
+EXPORT_SYMBOL_GPL(tegra210_plle_hw_sequence_start);
+
 void tegra210_xusb_pll_hw_control_enable(void)
 {
 	u32 val;
diff --git a/include/linux/clk/tegra.h b/include/linux/clk/tegra.h
index b8aef62cc3f5..07b6d6145c95 100644
--- a/include/linux/clk/tegra.h
+++ b/include/linux/clk/tegra.h
@@ -110,6 +110,8 @@  static inline void tegra_cpu_clock_resume(void)
 }
 #endif
 
+extern void tegra210_plle_hw_sequence_start(void);
+extern bool tegra210_plle_hw_sequence_is_enabled(void);
 extern void tegra210_xusb_pll_hw_control_enable(void);
 extern void tegra210_xusb_pll_hw_sequence_start(void);
 extern void tegra210_sata_pll_hw_control_enable(void);