| Message ID | 20190614074652.21960-2-jckuo@nvidia.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Tegra XHCI controller ELPG support | expand |
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
On 7/4/19 8:16 PM, Jon Hunter wrote: > > 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() ..." Thanks. I will amend the commit message accordingly. > > 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? Yes, tegra210_plle_hw_sequence_start() has to be invoked after PLLE is enabled/locked. Caller is in charge of calling with correct sequence. I will add a check in tegra210_plle_hw_sequence_start() to ensure that PLLE HW sequencer will not be accidentally enabled when PLLE is not enabled/locked yet. Thanks, JC
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);
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(+)