[U-Boot] [PATCH v6 16/26] tegra124: clock: Add display clocks and functions

Simon Glass
2015-04-15T03:03:34Z

Add functions to provide access to the display clocks on Tegra124 including
setting the clock rate for an EDP display.

Signed-off-by: Simon Glass <sjg@chromium.org>
---

Changes in v6: None
Changes in v4: None
Changes in v3: None
Changes in v2: None

arch/arm/include/asm/arch-tegra/clk_rst.h | 15 ++-
arch/arm/include/asm/arch-tegra124/clock-tables.h | 3 +-
arch/arm/include/asm/arch-tegra124/clock.h | 21 ++++
arch/arm/mach-tegra/clock.c | 2 +
arch/arm/mach-tegra/tegra124/clock.c | 141 +++++++++++++++++++++-
5 files changed, 173 insertions(+), 9 deletions(-)

diff --git a/arch/arm/include/asm/arch-tegra/clk_rst.h b/arch/arm/include/asm/arch-tegra/clk_rst.h
index 7d28e16..de50e08 100644
--- a/arch/arm/include/asm/arch-tegra/clk_rst.h
+++ b/arch/arm/include/asm/arch-tegra/clk_rst.h
@@ -202,9 +202,13 @@ struct clk_rst_ctlr {
uint crc_reserved52[1]; /* _reserved_52, 0x554 */
uint crc_super_gr3d_clk_div; /* _SUPER_GR3D_CLK_DIVIDER_0, 0x558 */
uint crc_spare_reg0; /* _SPARE_REG0_0, 0x55C */
-
- /* Tegra124 - skip to 0x600 here for new CLK_SOURCE_ regs */
- uint crc_reserved60[40]; /* _reserved_60, 0x560 - 0x5FC */
+ u32 _rsv32[4]; /* 0x560-0x56c */
+ u32 crc_plld2_ss_cfg; /* _PLLD2_SS_CFG 0x570 */
+ u32 _rsv32_1[7]; /* 0x574-58c */
+ struct clk_pll_simple plldp; /* _PLLDP_BASE, 0x590 _PLLDP_MISC */
+ u32 crc_plldp_ss_cfg; /* _PLLDP_SS_CFG, 0x598 */
+ u32 _rsrv32_2[25];
+ /* Tegra124 */
uint crc_clk_src_x[TEGRA_CLK_SOURCES_X]; /* XUSB, etc, 0x600-0x678 */
};

@@ -440,4 +444,9 @@ enum {
#define PLLX_IDDQ_SHIFT 3
#define PLLX_IDDQ_MASK (1U << PLLX_IDDQ_SHIFT)

+/* CLK_RST_PLLDP_SS_CFG */
+#define PLLDP_SS_CFG_CLAMP (1 << 22)
+#define PLLDP_SS_CFG_UNDOCUMENTED (1 << 24)
+#define PLLDP_SS_CFG_DITHER (1 << 28)
+
#endif /* _TEGRA_CLK_RST_H_ */
diff --git a/arch/arm/include/asm/arch-tegra124/clock-tables.h b/arch/arm/include/asm/arch-tegra124/clock-tables.h
index daf9a2b..7005855 100644
--- a/arch/arm/include/asm/arch-tegra124/clock-tables.h
+++ b/arch/arm/include/asm/arch-tegra124/clock-tables.h
@@ -25,6 +25,7 @@ enum clock_id {
CLOCK_ID_XCPU = CLOCK_ID_FIRST_SIMPLE,
CLOCK_ID_EPCI,
CLOCK_ID_SFROM32KHZ,
+ CLOCK_ID_DP, /* Special for Tegra124 */

/* These are the base clocks (inputs to the Tegra SoC) */
CLOCK_ID_32KHZ,
@@ -424,7 +425,7 @@ enum periphc_internal_id {

/* 0x58 */
PERIPHC_58h,
- PERIPHC_59h,
+ PERIPHC_SOR,
PERIPHC_5ah,
PERIPHC_5bh,
PERIPHC_SATAOOB,
diff --git a/arch/arm/include/asm/arch-tegra124/clock.h b/arch/arm/include/asm/arch-tegra124/clock.h
index 8e65086..e202cc5 100644
--- a/arch/arm/include/asm/arch-tegra124/clock.h
+++ b/arch/arm/include/asm/arch-tegra124/clock.h
@@ -16,6 +16,27 @@
#define OSC_FREQ_SHIFT 28
#define OSC_FREQ_MASK (0xF << OSC_FREQ_SHIFT)

+/* CLK_RST_CONTROLLER_CLK_SOURCE_SOR0_0 */
+#define SOR0_CLK_SEL0 (1 << 14)
+#define SOR0_CLK_SEL1 (1 << 15)
+
int tegra_plle_enable(void);

+void clock_sor_enable_edp_clock(void);
+
+/**
+ * clock_set_display_rate() - Set the display clock rate
+ *
+ * @frequency: the requested PLLD frequency
+ *
+ * Return the PLLD frequenc (which may not quite what was requested), or 0
+ * on failure
+ */
+u32 clock_set_display_rate(u32 frequency);
+
+/**
+ * clock_set_up_plldp() - Set up the EDP clock ready for use
+ */
+void clock_set_up_plldp(void);
+
#endif /* _TEGRA124_CLOCK_H_ */
diff --git a/arch/arm/mach-tegra/clock.c b/arch/arm/mach-tegra/clock.c
index 4b58cc1..cdd5438 100644
--- a/arch/arm/mach-tegra/clock.c
+++ b/arch/arm/mach-tegra/clock.c
@@ -593,6 +593,7 @@ void clock_init(void)
pll_rate[CLOCK_ID_MEMORY] = clock_get_rate(CLOCK_ID_MEMORY);
pll_rate[CLOCK_ID_PERIPH] = clock_get_rate(CLOCK_ID_PERIPH);
pll_rate[CLOCK_ID_CGENERAL] = clock_get_rate(CLOCK_ID_CGENERAL);
+ pll_rate[CLOCK_ID_DISPLAY] = clock_get_rate(CLOCK_ID_DISPLAY);
pll_rate[CLOCK_ID_OSC] = clock_get_rate(CLOCK_ID_OSC);
pll_rate[CLOCK_ID_SFROM32KHZ] = 32768;
pll_rate[CLOCK_ID_XCPU] = clock_get_rate(CLOCK_ID_XCPU);
@@ -600,6 +601,7 @@ void clock_init(void)
debug("PLLM = %d\n", pll_rate[CLOCK_ID_MEMORY]);
debug("PLLP = %d\n", pll_rate[CLOCK_ID_PERIPH]);
debug("PLLC = %d\n", pll_rate[CLOCK_ID_CGENERAL]);
+ debug("PLLD = %d\n", pll_rate[CLOCK_ID_DISPLAY]);
debug("PLLX = %d\n", pll_rate[CLOCK_ID_XCPU]);

/* Do any special system timer/TSC setup */
diff --git a/arch/arm/mach-tegra/tegra124/clock.c b/arch/arm/mach-tegra/tegra124/clock.c
index fc8bd19..2d17550 100644
--- a/arch/arm/mach-tegra/tegra124/clock.c
+++ b/arch/arm/mach-tegra/tegra124/clock.c
@@ -42,6 +42,7 @@ enum clock_type_id {
CLOCK_TYPE_ASPTE,
CLOCK_TYPE_PMDACD2T,
CLOCK_TYPE_PCST,
+ CLOCK_TYPE_DP,

CLOCK_TYPE_PC2CC3M,
CLOCK_TYPE_PC2CC3S_T,
@@ -101,6 +102,10 @@ static enum clock_id clock_source[CLOCK_TYPE_COUNT][CLOCK_MAX_MUX+1] = {
{ CLK(PERIPH), CLK(CGENERAL), CLK(SFROM32KHZ), CLK(OSC),
CLK(NONE), CLK(NONE), CLK(NONE), CLK(NONE),
MASK_BITS_31_28},
+ /* CLOCK_TYPE_DP */
+ { CLK(NONE), CLK(NONE), CLK(NONE), CLK(NONE),
+ CLK(NONE), CLK(NONE), CLK(NONE), CLK(NONE),
+ MASK_BITS_31_28},

/* Additional clock types on Tegra114+ */
/* CLOCK_TYPE_PC2CC3M */
@@ -259,7 +264,7 @@ static enum clock_type_id clock_periph_type[PERIPHC_COUNT] = {

/* 0x58 */
TYPE(PERIPHC_58h, CLOCK_TYPE_NONE),
- TYPE(PERIPHC_59h, CLOCK_TYPE_NONE),
+ TYPE(PERIPHC_SOR, CLOCK_TYPE_NONE),
TYPE(PERIPHC_5ah, CLOCK_TYPE_NONE),
TYPE(PERIPHC_5bh, CLOCK_TYPE_NONE),
TYPE(PERIPHC_SATAOOB, CLOCK_TYPE_PCMT),
@@ -546,7 +551,7 @@ static s8 periph_id_to_internal_id[PERIPH_ID_COUNT] = {
NONE(X_RESERVED19),
NONE(ADX1),
NONE(DPAUX),
- NONE(SOR0),
+ PERIPHC_SOR,
NONE(X_RESERVED23),

/* 184 */
@@ -594,7 +599,10 @@ u32 *get_periph_source_reg(enum periph_id periph_id)
assert(periph_id >= PERIPH_ID_FIRST && periph_id < PERIPH_ID_COUNT);
internal_id = periph_id_to_internal_id[periph_id];
assert(internal_id != -1);
- if (internal_id >= PERIPHC_VW_FIRST) {
+ if (internal_id >= PERIPHC_X_FIRST) {
+ internal_id -= PERIPHC_X_FIRST;
+ return &clkrst->crc_clk_src_x[internal_id];
+ } else if (internal_id >= PERIPHC_VW_FIRST) {
internal_id -= PERIPHC_VW_FIRST;
return &clkrst->crc_clk_src_vw[internal_id];
} else {
@@ -657,8 +665,10 @@ void clock_set_enable(enum periph_id periph_id, int enable)
assert(clock_periph_id_isvalid(periph_id));
if ((int)periph_id < (int)PERIPH_ID_VW_FIRST)
clk = &clkrst->crc_clk_out_enb[PERIPH_REG(periph_id)];
- else
+ else if ((int)periph_id < PERIPH_ID_X_FIRST)
clk = &clkrst->crc_clk_out_enb_vw[PERIPH_REG(periph_id)];
+ else
+ clk = &clkrst->crc_clk_out_enb_x;
reg = readl(clk);
if (enable)
reg |= PERIPH_MASK(periph_id);
@@ -678,8 +688,10 @@ void reset_set_enable(enum periph_id periph_id, int enable)
assert(clock_periph_id_isvalid(periph_id));
if (periph_id < PERIPH_ID_VW_FIRST)
reset = &clkrst->crc_rst_dev[PERIPH_REG(periph_id)];
- else
+ else if ((int)periph_id < PERIPH_ID_X_FIRST)
reset = &clkrst->crc_rst_dev_vw[PERIPH_REG(periph_id)];
+ else
+ reset = &clkrst->crc_rst_devices_x;
reg = readl(reset);
if (enable)
reg |= PERIPH_MASK(periph_id);
@@ -933,3 +945,122 @@ int tegra_plle_enable(void)

return 0;
}
+
+void clock_sor_enable_edp_clock(void)
+{
+ u32 *reg;
+
+ /* uses PLLP, has a non-standard bit layout. */
+ reg = get_periph_source_reg(PERIPH_ID_SOR0);
+ setbits_le32(reg, SOR0_CLK_SEL0);
+}
+
+u32 clock_set_display_rate(u32 frequency)
+{
+ /**
+ * plld (fo) = vco >> p, where 500MHz < vco < 1000MHz
+ * = (cf * n) >> p, where 1MHz < cf < 6MHz
+ * = ((ref / m) * n) >> p
+ *
+ * Iterate the possible values of p (3 bits, 2^7) to find out a minimum
+ * safe vco, then find best (m, n). since m has only 5 bits, we can
+ * iterate all possible values. Note Tegra 124 supports 11 bits for n,
+ * but our pll_fields has only 10 bits for n.
+ *
+ * Note values undershoot or overshoot target output frequency may not
+ * work if the values are not in "safe" range by panel specification.
+ */
+ u32 ref = clock_get_rate(CLOCK_ID_OSC);
+ u32 divm, divn, divp, cpcon;
+ u32 cf, vco, rounded_rate = frequency;
+ u32 diff, best_diff, best_m = 0, best_n = 0, best_p;
+ const u32 max_m = 1 << 5, max_n = 1 << 10, max_p = 1 << 3,
+ mhz = 1000 * 1000, min_vco = 500 * mhz, max_vco = 1000 * mhz,
+ min_cf = 1 * mhz, max_cf = 6 * mhz;
+ int mux_bits, divider_bits, source;
+
+ for (divp = 0, vco = frequency; vco < min_vco && divp < max_p; divp++)
+ vco <<= 1;
+
+ if (vco < min_vco || vco > max_vco) {
+ printf("%s: Cannot find out a supported VCO for Frequency (%u)\n",
+ __func__, frequency);
+ return 0;
+ }
+
+ best_p = divp;
+ best_diff = vco;
+
+ for (divm = 1; divm < max_m && best_diff; divm++) {
+ cf = ref / divm;
+ if (cf < min_cf)
+ break;
+ if (cf > max_cf)
+ continue;
+
+ divn = vco / cf;
+ if (divn >= max_n)
+ continue;
+
+ diff = vco - divn * cf;
+ if (divn + 1 < max_n && diff > cf / 2) {
+ divn++;
+ diff = cf - diff;
+ }
+
+ if (diff >= best_diff)
+ continue;
+
+ best_diff = diff;
+ best_m = divm;
+ best_n = divn;
+ }
+
+ if (best_n < 50)
+ cpcon = 2;
+ else if (best_n < 300)
+ cpcon = 3;
+ else if (best_n < 600)
+ cpcon = 8;
+ else
+ cpcon = 12;
+
+ if (best_diff) {
+ printf("%s: Failed to match output frequency %u, best difference is %u\n",
+ __func__, frequency, best_diff);
+ rounded_rate = (ref / best_m * best_n) >> best_p;
+ }
+
+ debug("%s: PLLD=%u ref=%u, m/n/p/cpcon=%u/%u/%u/%u\n",
+ __func__, rounded_rate, ref, best_m, best_n, best_p, cpcon);
+
+ source = get_periph_clock_source(PERIPH_ID_DISP1, CLOCK_ID_DISPLAY,
+ &mux_bits, &divider_bits);
+ clock_ll_set_source_bits(PERIPH_ID_DISP1, mux_bits, source);
+ clock_set_rate(CLOCK_ID_DISPLAY, best_n, best_m, best_p, cpcon);
+
+ return rounded_rate;
+}
+
+void clock_set_up_plldp(void)
+{
+ struct clk_rst_ctlr *clkrst =
+ (struct clk_rst_ctlr *)NV_PA_CLK_RST_BASE;
+ u32 value;
+
+ value = PLLDP_SS_CFG_UNDOCUMENTED | PLLDP_SS_CFG_DITHER;
+ writel(value | PLLDP_SS_CFG_CLAMP, &clkrst->crc_plldp_ss_cfg);
+ clock_start_pll(CLOCK_ID_DP, 1, 90, 3, 0, 0);
+ writel(value, &clkrst->crc_plldp_ss_cfg);
+}
+
+struct clk_pll_simple *clock_get_simple_pll(enum clock_id clkid)
+{
+ struct clk_rst_ctlr *clkrst =
+ (struct clk_rst_ctlr *)NV_PA_CLK_RST_BASE;
+
+ if (clkid == CLOCK_ID_DP)
+ return &clkrst->plldp;
+
+ return NULL;
+}
--
2.2.0.rc0.207.ga3a616c