[U-Boot] [PATCH 14/21] ARM: tegra: add peripheral clock init table

Stephen Warren swarren at wwwdotorg.org
Tue Sep 13 18:45:55 CEST 2016 

From: Stephen Warren <swarren at nvidia.com>

Currently, Tegra peripheral drivers control two aspects of their HW module
clock(s):

1) The clock enable/rate for the peripheral clock itself.

2) The system-level clock tree setup, i.e. the clock parent.

Aspect 1 is reasonable, but aspect 2 is a system-level decision, not
something that an individual peripheral driver should in general know
about or influence. Such system-level knowledge ties the driver to a
specific SoC implementation, even when they use generic APIs for clock
manipulation, since they must have SoC-specific knowledge such as parent
clock IDs. Limited exceptions exist, such as where peripheral HW is
expected to dynamically switch between clock sources at run-time, such
as CPU clock scaling or display clock conflict management in a multi-head
scenario.

This patch enhances the Tegra core code to perform system-level clock
tree setup, in a similar fashion to the Linux kernel Tegra clock driver.
This will allow future patches to simplify peripheral drivers by removing
the clock parent setup logic.

This change is required prior to converting peripheral drivers to use the
standard clock APIs, since:

1) The clock uclass doesn't currently support a set_parent() operation.
Adding one is possible, but not necessary at the moment.

2) The clock APIs retrieve all clock IDs from device tree, and the DT
bindings for almost all peripherals only includes information about the
relevant peripheral clocks, and not any potential parent clocks.

Signed-off-by: Stephen Warren <swarren at nvidia.com>
---
 arch/arm/include/asm/arch-tegra/clock.h |  6 ++++++
 arch/arm/mach-tegra/clock.c             | 15 +++++++++++++++
 arch/arm/mach-tegra/tegra114/clock.c    | 23 +++++++++++++++++++++++
 arch/arm/mach-tegra/tegra124/clock.c    | 23 +++++++++++++++++++++++
 arch/arm/mach-tegra/tegra20/clock.c     | 21 +++++++++++++++++++++
 arch/arm/mach-tegra/tegra210/clock.c    | 23 +++++++++++++++++++++++
 arch/arm/mach-tegra/tegra30/clock.c     | 23 +++++++++++++++++++++++
 7 files changed, 134 insertions(+)

diff --git a/arch/arm/include/asm/arch-tegra/clock.h b/arch/arm/include/asm/arch-tegra/clock.h
index 7daf8bc1632a..e0737f574add 100644
--- a/arch/arm/include/asm/arch-tegra/clock.h
+++ b/arch/arm/include/asm/arch-tegra/clock.h
@@ -362,6 +362,12 @@ struct clk_pll_info {
 };
 extern struct clk_pll_info tegra_pll_info_table[CLOCK_ID_PLL_COUNT];
 
+struct periph_clk_init {
+	enum periph_id periph_id;
+	enum clock_id parent_clock_id;
+};
+extern struct periph_clk_init periph_clk_init_table[];
+
 /**
  * Enable output clock for external peripherals
  *
diff --git a/arch/arm/mach-tegra/clock.c b/arch/arm/mach-tegra/clock.c
index 36eabc8f5721..597f6286d6c1 100644
--- a/arch/arm/mach-tegra/clock.c
+++ b/arch/arm/mach-tegra/clock.c
@@ -612,6 +612,8 @@ int clock_verify(void)
 
 void clock_init(void)
 {
+	int i;
+
 	pll_rate[CLOCK_ID_CGENERAL] = clock_get_rate(CLOCK_ID_CGENERAL);
 	pll_rate[CLOCK_ID_MEMORY] = clock_get_rate(CLOCK_ID_MEMORY);
 	pll_rate[CLOCK_ID_PERIPH] = clock_get_rate(CLOCK_ID_PERIPH);
@@ -630,6 +632,19 @@ void clock_init(void)
 	debug("PLLU = %d\n", pll_rate[CLOCK_ID_USB]);
 	debug("PLLD = %d\n", pll_rate[CLOCK_ID_DISPLAY]);
 	debug("PLLX = %d\n", pll_rate[CLOCK_ID_XCPU]);
+
+	for (i = 0; periph_clk_init_table[i].periph_id != -1; i++) {
+		enum periph_id periph_id;
+		enum clock_id parent;
+		int source, mux_bits, divider_bits;
+
+		periph_id = periph_clk_init_table[i].periph_id;
+		parent = periph_clk_init_table[i].parent_clock_id;
+
+		source = get_periph_clock_source(periph_id, parent, &mux_bits,
+						 &divider_bits);
+		clock_ll_set_source_bits(periph_id, mux_bits, source);
+	}
 }
 
 static void set_avp_clock_source(u32 src)
diff --git a/arch/arm/mach-tegra/tegra114/clock.c b/arch/arm/mach-tegra/tegra114/clock.c
index e6ef873c8dc4..6620206be0ba 100644
--- a/arch/arm/mach-tegra/tegra114/clock.c
+++ b/arch/arm/mach-tegra/tegra114/clock.c
@@ -699,3 +699,26 @@ void arch_timer_init(void)
 	writel(val, &sysctr->cntcr);
 	debug("%s: TSC CNTCR = 0x%08X\n", __func__, val);
 }
+
+struct periph_clk_init periph_clk_init_table[] = {
+	{ PERIPH_ID_SBC1, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_SBC2, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_SBC3, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_SBC4, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_SBC5, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_SBC6, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_HOST1X, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_DISP1, CLOCK_ID_CGENERAL },
+	{ PERIPH_ID_NDFLASH, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_SDMMC1, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_SDMMC2, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_SDMMC3, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_SDMMC4, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_PWM, CLOCK_ID_SFROM32KHZ },
+	{ PERIPH_ID_I2C1, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_I2C2, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_I2C3, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_I2C4, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_I2C5, CLOCK_ID_PERIPH },
+	{ -1, },
+};
diff --git a/arch/arm/mach-tegra/tegra124/clock.c b/arch/arm/mach-tegra/tegra124/clock.c
index 1e71146236e9..84b679c1c54b 100644
--- a/arch/arm/mach-tegra/tegra124/clock.c
+++ b/arch/arm/mach-tegra/tegra124/clock.c
@@ -1107,3 +1107,26 @@ struct clk_pll_simple *clock_get_simple_pll(enum clock_id clkid)
 
 	return NULL;
 }
+
+struct periph_clk_init periph_clk_init_table[] = {
+	{ PERIPH_ID_SBC1, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_SBC2, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_SBC3, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_SBC4, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_SBC5, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_SBC6, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_HOST1X, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_DISP1, CLOCK_ID_CGENERAL },
+	{ PERIPH_ID_SDMMC1, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_SDMMC2, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_SDMMC3, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_SDMMC4, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_PWM, CLOCK_ID_SFROM32KHZ },
+	{ PERIPH_ID_I2C1, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_I2C2, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_I2C3, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_I2C4, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_I2C5, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_I2C6, CLOCK_ID_PERIPH },
+	{ -1, },
+};
diff --git a/arch/arm/mach-tegra/tegra20/clock.c b/arch/arm/mach-tegra/tegra20/clock.c
index cd9fb9a55340..d11e89bd253f 100644
--- a/arch/arm/mach-tegra/tegra20/clock.c
+++ b/arch/arm/mach-tegra/tegra20/clock.c
@@ -717,3 +717,24 @@ int tegra_plle_enable(void)
 
 	return 0;
 }
+
+struct periph_clk_init periph_clk_init_table[] = {
+	{ PERIPH_ID_SPI1, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_SBC1, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_SBC2, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_SBC3, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_SBC4, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_HOST1X, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_DISP1, CLOCK_ID_CGENERAL },
+	{ PERIPH_ID_NDFLASH, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_SDMMC1, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_SDMMC2, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_SDMMC3, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_SDMMC4, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_PWM, CLOCK_ID_SFROM32KHZ },
+	{ PERIPH_ID_DVC_I2C, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_I2C1, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_I2C2, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_I2C3, CLOCK_ID_PERIPH },
+	{ -1, },
+};
diff --git a/arch/arm/mach-tegra/tegra210/clock.c b/arch/arm/mach-tegra/tegra210/clock.c
index f0052e7934a1..d51c1481ea20 100644
--- a/arch/arm/mach-tegra/tegra210/clock.c
+++ b/arch/arm/mach-tegra/tegra210/clock.c
@@ -1225,3 +1225,26 @@ int tegra_plle_enable(void)
 
 	return 0;
 }
+
+struct periph_clk_init periph_clk_init_table[] = {
+	{ PERIPH_ID_SBC1, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_SBC2, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_SBC3, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_SBC4, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_SBC5, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_SBC6, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_HOST1X, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_DISP1, CLOCK_ID_CGENERAL },
+	{ PERIPH_ID_SDMMC1, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_SDMMC2, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_SDMMC3, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_SDMMC4, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_PWM, CLOCK_ID_SFROM32KHZ },
+	{ PERIPH_ID_I2C1, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_I2C2, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_I2C3, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_I2C4, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_I2C5, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_I2C6, CLOCK_ID_PERIPH },
+	{ -1, },
+};
diff --git a/arch/arm/mach-tegra/tegra30/clock.c b/arch/arm/mach-tegra/tegra30/clock.c
index 1f104f288e57..52a6dcebdfcd 100644
--- a/arch/arm/mach-tegra/tegra30/clock.c
+++ b/arch/arm/mach-tegra/tegra30/clock.c
@@ -763,3 +763,26 @@ int tegra_plle_enable(void)
 
 	return 0;
 }
+
+struct periph_clk_init periph_clk_init_table[] = {
+	{ PERIPH_ID_SBC1, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_SBC2, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_SBC3, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_SBC4, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_SBC5, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_SBC6, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_HOST1X, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_DISP1, CLOCK_ID_CGENERAL },
+	{ PERIPH_ID_NDFLASH, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_SDMMC1, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_SDMMC2, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_SDMMC3, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_SDMMC4, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_PWM, CLOCK_ID_SFROM32KHZ },
+	{ PERIPH_ID_DVC_I2C, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_I2C1, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_I2C2, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_I2C3, CLOCK_ID_PERIPH },
+	{ PERIPH_ID_I2C4, CLOCK_ID_PERIPH },
+	{ -1, },
+};
-- 
2.9.3

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