2018-07-03 11:37:29

by Aapo Vienamo

[permalink] [raw]
Subject: [PATCH 1/3] clk: tegra: refactor 7.1 div calculation

From: Peter De Schrijver <[email protected]>

Move this to a separate file so it can be used to calculate the sdmmc
clock dividers.

Signed-off-by: Peter De-Schrijver <[email protected]>
Signed-off-by: Aapo Vienamo <[email protected]>
---
drivers/clk/tegra/Makefile | 1 +
drivers/clk/tegra/clk-divider.c | 30 ++++--------------------
drivers/clk/tegra/clk.h | 3 +++
drivers/clk/tegra/div71.c | 51 +++++++++++++++++++++++++++++++++++++++++
4 files changed, 60 insertions(+), 25 deletions(-)
create mode 100644 drivers/clk/tegra/div71.c

diff --git a/drivers/clk/tegra/Makefile b/drivers/clk/tegra/Makefile
index b716923..6d4f563 100644
--- a/drivers/clk/tegra/Makefile
+++ b/drivers/clk/tegra/Makefile
@@ -24,3 +24,4 @@ obj-$(CONFIG_ARCH_TEGRA_132_SOC) += clk-tegra124.o
obj-y += cvb.o
obj-$(CONFIG_ARCH_TEGRA_210_SOC) += clk-tegra210.o
obj-$(CONFIG_CLK_TEGRA_BPMP) += clk-bpmp.o
+obj-y += div71.o
diff --git a/drivers/clk/tegra/clk-divider.c b/drivers/clk/tegra/clk-divider.c
index 16e0aee..ad87858 100644
--- a/drivers/clk/tegra/clk-divider.c
+++ b/drivers/clk/tegra/clk-divider.c
@@ -32,35 +32,15 @@
static int get_div(struct tegra_clk_frac_div *divider, unsigned long rate,
unsigned long parent_rate)
{
- u64 divider_ux1 = parent_rate;
- u8 flags = divider->flags;
- int mul;
-
- if (!rate)
- return 0;
-
- mul = get_mul(divider);
-
- if (!(flags & TEGRA_DIVIDER_INT))
- divider_ux1 *= mul;
-
- if (flags & TEGRA_DIVIDER_ROUND_UP)
- divider_ux1 += rate - 1;
-
- do_div(divider_ux1, rate);
-
- if (flags & TEGRA_DIVIDER_INT)
- divider_ux1 *= mul;
+ int div;

- divider_ux1 -= mul;
+ div = div71_get(rate, parent_rate, divider->width, divider->frac_width,
+ divider->flags);

- if ((s64)divider_ux1 < 0)
+ if (div < 0)
return 0;

- if (divider_ux1 > get_max_div(divider))
- return get_max_div(divider);
-
- return divider_ux1;
+ return div;
}

static unsigned long clk_frac_div_recalc_rate(struct clk_hw *hw,
diff --git a/drivers/clk/tegra/clk.h b/drivers/clk/tegra/clk.h
index e1f8846..f14e136 100644
--- a/drivers/clk/tegra/clk.h
+++ b/drivers/clk/tegra/clk.h
@@ -811,6 +811,9 @@ extern tegra_clk_apply_init_table_func tegra_clk_apply_init_table;
int tegra_pll_wait_for_lock(struct tegra_clk_pll *pll);
u16 tegra_pll_get_fixed_mdiv(struct clk_hw *hw, unsigned long input_rate);
int tegra_pll_p_div_to_hw(struct tegra_clk_pll *pll, u8 p_div);
+int div71_get(unsigned long rate, unsigned parent_rate, u8 width,
+ u8 frac_width, u8 flags);
+

/* Combined read fence with delay */
#define fence_udelay(delay, reg) \
diff --git a/drivers/clk/tegra/div71.c b/drivers/clk/tegra/div71.c
new file mode 100644
index 0000000..27b3846
--- /dev/null
+++ b/drivers/clk/tegra/div71.c
@@ -0,0 +1,51 @@
+/*
+ * Copyright (c) 2018, NVIDIA CORPORATION. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/kernel.h>
+
+#include "clk.h"
+
+#define div_mask(w) ((1 << (w)) - 1)
+
+int div71_get(unsigned long rate, unsigned parent_rate, u8 width,
+ u8 frac_width, u8 flags)
+{
+ s64 divider_ux1 = parent_rate;
+ int mul;
+
+ if (!rate)
+ return 0;
+
+ mul = 1 << frac_width;
+
+ if (!(flags & TEGRA_DIVIDER_INT))
+ divider_ux1 *= mul;
+
+ if (flags & TEGRA_DIVIDER_ROUND_UP)
+ divider_ux1 += rate - 1;
+
+ do_div(divider_ux1, rate);
+
+ if (flags & TEGRA_DIVIDER_INT)
+ divider_ux1 *= mul;
+
+ divider_ux1 -= mul;
+
+ if (divider_ux1 > div_mask(width))
+ return div_mask(width);
+
+ return divider_ux1;
+}
--
2.7.4



2018-07-03 11:36:47

by Aapo Vienamo

[permalink] [raw]
Subject: [PATCH 3/3] clk: tegra: make sdmmc2 and sdmmc4 as sdmmc clocks

From: Peter De-Schrijver <[email protected]>

These clock have low jitter paths to certain parents. To model these
correctly, use the sdmmc mux divider clock type.

Signed-off-by: Peter De-Schrijver <[email protected]>
Signed-off-by: Aapo Vienamo <[email protected]>
---
drivers/clk/tegra/clk-id.h | 2 --
drivers/clk/tegra/clk-tegra-periph.c | 11 -----------
drivers/clk/tegra/clk-tegra210.c | 14 ++++++++++++--
3 files changed, 12 insertions(+), 15 deletions(-)

diff --git a/drivers/clk/tegra/clk-id.h b/drivers/clk/tegra/clk-id.h
index b616e33..de466b4 100644
--- a/drivers/clk/tegra/clk-id.h
+++ b/drivers/clk/tegra/clk-id.h
@@ -227,13 +227,11 @@ enum clk_id {
tegra_clk_sdmmc1_9,
tegra_clk_sdmmc2,
tegra_clk_sdmmc2_8,
- tegra_clk_sdmmc2_9,
tegra_clk_sdmmc3,
tegra_clk_sdmmc3_8,
tegra_clk_sdmmc3_9,
tegra_clk_sdmmc4,
tegra_clk_sdmmc4_8,
- tegra_clk_sdmmc4_9,
tegra_clk_se,
tegra_clk_soc_therm,
tegra_clk_soc_therm_8,
diff --git a/drivers/clk/tegra/clk-tegra-periph.c b/drivers/clk/tegra/clk-tegra-periph.c
index 2acba29..38c4eb2 100644
--- a/drivers/clk/tegra/clk-tegra-periph.c
+++ b/drivers/clk/tegra/clk-tegra-periph.c
@@ -451,15 +451,6 @@ static u32 mux_pllp_pllc4_out2_pllc4_out1_clkm_pllc4_out0_idx[] = {
[0] = 0, [1] = 3, [2] = 4, [3] = 6, [4] = 7,
};

-static const char *mux_pllp_clkm_pllc4_out2_out1_out0_lj[] = {
- "pll_p",
- "pll_c4_out2", "pll_c4_out0", /* LJ input */
- "pll_c4_out2", "pll_c4_out1",
- "pll_c4_out1", /* LJ input */
- "clk_m", "pll_c4_out0"
-};
-#define mux_pllp_clkm_pllc4_out2_out1_out0_lj_idx NULL
-
static const char *mux_pllp_pllc2_c_c3_clkm[] = {
"pll_p", "pll_c2", "pll_c", "pll_c3", "clk_m"
};
@@ -686,9 +677,7 @@ static struct tegra_periph_init_data periph_clks[] = {
MUX("sdmmc3", mux_pllp_pllc_pllm_clkm, CLK_SOURCE_SDMMC3, 69, TEGRA_PERIPH_ON_APB, tegra_clk_sdmmc3),
MUX("sdmmc4", mux_pllp_pllc_pllm_clkm, CLK_SOURCE_SDMMC4, 15, TEGRA_PERIPH_ON_APB, tegra_clk_sdmmc4),
MUX8("sdmmc1", mux_pllp_pllc4_out2_pllc4_out1_clkm_pllc4_out0, CLK_SOURCE_SDMMC1, 14, TEGRA_PERIPH_ON_APB, tegra_clk_sdmmc1_9),
- MUX8("sdmmc2", mux_pllp_clkm_pllc4_out2_out1_out0_lj, CLK_SOURCE_SDMMC2, 9, TEGRA_PERIPH_ON_APB, tegra_clk_sdmmc2_9),
MUX8("sdmmc3", mux_pllp_pllc4_out2_pllc4_out1_clkm_pllc4_out0, CLK_SOURCE_SDMMC3, 69, TEGRA_PERIPH_ON_APB, tegra_clk_sdmmc3_9),
- MUX8("sdmmc4", mux_pllp_clkm_pllc4_out2_out1_out0_lj, CLK_SOURCE_SDMMC4, 15, TEGRA_PERIPH_ON_APB, tegra_clk_sdmmc4_9),
MUX("la", mux_pllp_pllc_pllm_clkm, CLK_SOURCE_LA, 76, TEGRA_PERIPH_ON_APB, tegra_clk_la),
MUX("trace", mux_pllp_pllc_pllm_clkm, CLK_SOURCE_TRACE, 77, TEGRA_PERIPH_ON_APB, tegra_clk_trace),
MUX("owr", mux_pllp_pllc_pllm_clkm, CLK_SOURCE_OWR, 71, TEGRA_PERIPH_ON_APB, tegra_clk_owr),
diff --git a/drivers/clk/tegra/clk-tegra210.c b/drivers/clk/tegra/clk-tegra210.c
index 5435d01..9eb1cb1 100644
--- a/drivers/clk/tegra/clk-tegra210.c
+++ b/drivers/clk/tegra/clk-tegra210.c
@@ -44,6 +44,8 @@
#define CLK_SOURCE_EMC 0x19c
#define CLK_SOURCE_SOR1 0x410
#define CLK_SOURCE_LA 0x1f8
+#define CLK_SOURCE_SDMMC2 0x154
+#define CLK_SOURCE_SDMMC4 0x164

#define PLLC_BASE 0x80
#define PLLC_OUT 0x84
@@ -2286,11 +2288,9 @@ static struct tegra_clk tegra210_clks[tegra_clk_max] __initdata = {
[tegra_clk_rtc] = { .dt_id = TEGRA210_CLK_RTC, .present = true },
[tegra_clk_timer] = { .dt_id = TEGRA210_CLK_TIMER, .present = true },
[tegra_clk_uarta_8] = { .dt_id = TEGRA210_CLK_UARTA, .present = true },
- [tegra_clk_sdmmc2_9] = { .dt_id = TEGRA210_CLK_SDMMC2, .present = true },
[tegra_clk_i2s1] = { .dt_id = TEGRA210_CLK_I2S1, .present = true },
[tegra_clk_i2c1] = { .dt_id = TEGRA210_CLK_I2C1, .present = true },
[tegra_clk_sdmmc1_9] = { .dt_id = TEGRA210_CLK_SDMMC1, .present = true },
- [tegra_clk_sdmmc4_9] = { .dt_id = TEGRA210_CLK_SDMMC4, .present = true },
[tegra_clk_pwm] = { .dt_id = TEGRA210_CLK_PWM, .present = true },
[tegra_clk_i2s2] = { .dt_id = TEGRA210_CLK_I2S2, .present = true },
[tegra_clk_usbd] = { .dt_id = TEGRA210_CLK_USBD, .present = true },
@@ -3030,6 +3030,16 @@ static __init void tegra210_periph_clk_init(void __iomem *clk_base,
0, NULL);
clks[TEGRA210_CLK_ACLK] = clk;

+ clk = tegra_clk_register_sdmmc_mux_div("sdmmc2", clk_base,
+ CLK_SOURCE_SDMMC2, 9,
+ TEGRA_DIVIDER_ROUND_UP, 0, NULL);
+ clks[TEGRA210_CLK_SDMMC2] = clk;
+
+ clk = tegra_clk_register_sdmmc_mux_div("sdmmc4", clk_base,
+ CLK_SOURCE_SDMMC4, 15,
+ TEGRA_DIVIDER_ROUND_UP, 0, NULL);
+ clks[TEGRA210_CLK_SDMMC4] = clk;
+
for (i = 0; i < ARRAY_SIZE(tegra210_periph); i++) {
struct tegra_periph_init_data *init = &tegra210_periph[i];
struct clk **clkp;
--
2.7.4


2018-07-03 11:36:59

by Aapo Vienamo

[permalink] [raw]
Subject: [PATCH 2/3] clk: tegra: Add sdmmc mux divider clock

From: Peter De-Schrijver <[email protected]>

Add a clock type to model the sdmmc switch divider clocks which have paths
to source clocks bypassing the divider (Low Jitter paths). These
are handled by selecting the lj path when the divider is 1 (ie the
rate is the parent rate), otherwise the normal path with divider
will be selected. Otherwise this clock behaves as a normal peripheral
clock.

Signed-off-by: Peter De-Schrijver <[email protected]>
Signed-off-by: Aapo Vienamo <[email protected]>
---
drivers/clk/tegra/Makefile | 1 +
drivers/clk/tegra/clk-sdmmc-mux.c | 254 ++++++++++++++++++++++++++++++++++++++
drivers/clk/tegra/clk.h | 27 ++++
3 files changed, 282 insertions(+)
create mode 100644 drivers/clk/tegra/clk-sdmmc-mux.c

diff --git a/drivers/clk/tegra/Makefile b/drivers/clk/tegra/Makefile
index 6d4f563..916f65b 100644
--- a/drivers/clk/tegra/Makefile
+++ b/drivers/clk/tegra/Makefile
@@ -8,6 +8,7 @@ obj-y += clk-periph-fixed.o
obj-y += clk-periph-gate.o
obj-y += clk-pll.o
obj-y += clk-pll-out.o
+obj-y += clk-sdmmc-mux.o
obj-y += clk-super.o
obj-y += clk-tegra-audio.o
obj-y += clk-tegra-periph.o
diff --git a/drivers/clk/tegra/clk-sdmmc-mux.c b/drivers/clk/tegra/clk-sdmmc-mux.c
new file mode 100644
index 0000000..8e19cb3
--- /dev/null
+++ b/drivers/clk/tegra/clk-sdmmc-mux.c
@@ -0,0 +1,254 @@
+/*
+ * Copyright (c) 2018 NVIDIA CORPORATION. All rights reserved.
+ *
+ * based on clk-mux.c
+
+ * Copyright (C) 2011 Sascha Hauer, Pengutronix <[email protected]>
+ * Copyright (C) 2011 Richard Zhao, Linaro <[email protected]>
+ * Copyright (C) 2011-2012 Mike Turquette, Linaro Ltd <[email protected]>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/err.h>
+#include <linux/types.h>
+
+#include "clk.h"
+
+#define DIV_MASK GENMASK(7, 0)
+#define MUX_SHIFT 29
+#define MUX_MASK GENMASK(MUX_SHIFT + 2, MUX_SHIFT)
+
+#define get_max_div(d) DIV_MASK
+#define get_div_field(val) ((val) & DIV_MASK)
+#define get_mux_field(val) (((val) & MUX_MASK) >> MUX_SHIFT)
+
+static const char * const mux_sdmmc_parents[] = { "pll_p", "pll_c4_out2",
+ "pll_c4_out0", "pll_c4_out1",
+ "clk_m" };
+static u8 mux_lj_idx[] = { [0] = 0, [1] = 1, [2] = 2, [3] = 5, [4] = 6 };
+static u8 mux_non_lj_idx[] = { [0] = 0, [1] = 3, [2] = 7, [3] = 4, [4] = 6 };
+
+static u8 clk_sdmmc_mux_get_parent(struct clk_hw *hw)
+{
+ struct tegra_sdmmc_mux *sdmmc_mux = to_clk_sdmmc_mux(hw);
+ int num_parents, i;
+ u32 src, val;
+ u8 *mux_idx;
+
+ num_parents = clk_hw_get_num_parents(hw);
+
+ val = readl_relaxed(sdmmc_mux->reg);
+ src = get_mux_field(val);
+ if (get_div_field(val))
+ mux_idx = mux_non_lj_idx;
+ else
+ mux_idx = mux_lj_idx;
+
+ for (i = 0; i < num_parents; i++) {
+ if (mux_idx[i] == src)
+ return i;
+ }
+
+ WARN(1, "Unknown parent selector %d\n", src);
+
+ return 0;
+}
+
+static int clk_sdmmc_mux_set_parent(struct clk_hw *hw, u8 index)
+{
+ struct tegra_sdmmc_mux *sdmmc_mux = to_clk_sdmmc_mux(hw);
+ u32 val;
+
+
+ val = readl_relaxed(sdmmc_mux->reg);
+ if (get_div_field(val))
+ index = mux_non_lj_idx[index];
+ else
+ index = mux_lj_idx[index];
+
+ val &= ~MUX_MASK;
+ val |= index << MUX_SHIFT;
+
+ writel(val, sdmmc_mux->reg);
+
+ return 0;
+}
+
+static unsigned long clk_sdmmc_mux_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct tegra_sdmmc_mux *sdmmc_mux = to_clk_sdmmc_mux(hw);
+ u32 val;
+ int div, mul;
+ u64 rate = parent_rate;
+
+ val = readl_relaxed(sdmmc_mux->reg);
+ div = get_div_field(val);
+
+ mul = 2;
+ div += mul;
+
+ rate *= mul;
+ rate += div - 1;
+ do_div(rate, div);
+
+ return rate;
+}
+
+static int clk_sdmmc_mux_determine_rate(struct clk_hw *hw,
+ struct clk_rate_request *req)
+{
+ struct tegra_sdmmc_mux *sdmmc_mux = to_clk_sdmmc_mux(hw);
+ int div, mul;
+ unsigned long output_rate = req->best_parent_rate;
+
+ req->rate = max(req->rate, req->min_rate);
+ req->rate = min(req->rate, req->max_rate);
+
+ if (!req->rate)
+ return output_rate;
+
+ div = div71_get(req->rate, output_rate, 8, 1, sdmmc_mux->div_flags);
+ if (div < 0)
+ div = 0;
+
+ mul = 2;
+ if (sdmmc_mux->div_flags & TEGRA_DIVIDER_ROUND_UP)
+ req->rate = DIV_ROUND_UP(output_rate * mul, div + mul);
+ else
+ req->rate = output_rate * mul / (div + mul);
+
+ return 0;
+}
+
+static int clk_sdmmc_mux_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct tegra_sdmmc_mux *sdmmc_mux = to_clk_sdmmc_mux(hw);
+ int div;
+ unsigned long flags = 0;
+ u32 val;
+ u8 src;
+
+ div = div71_get(rate, parent_rate, 8, 1, sdmmc_mux->div_flags);
+ if (div < 0)
+ return div;
+
+ if (sdmmc_mux->lock)
+ spin_lock_irqsave(sdmmc_mux->lock, flags);
+
+ src = clk_sdmmc_mux_get_parent(hw);
+ if (div)
+ src = mux_non_lj_idx[src];
+ else
+ src = mux_lj_idx[src];
+
+ val = src << MUX_SHIFT;
+ val |= div;
+ writel(val, sdmmc_mux->reg);
+ fence_udelay(2, sdmmc_mux->reg);
+
+ if (sdmmc_mux->lock)
+ spin_unlock_irqrestore(sdmmc_mux->lock, flags);
+
+ return 0;
+}
+
+static int clk_sdmmc_mux_is_enabled(struct clk_hw *hw)
+{
+ struct tegra_sdmmc_mux *sdmmc_mux = to_clk_sdmmc_mux(hw);
+ const struct clk_ops *gate_ops = sdmmc_mux->gate_ops;
+ struct clk_hw *gate_hw = &sdmmc_mux->gate.hw;
+
+ __clk_hw_set_clk(gate_hw, hw);
+
+ return gate_ops->is_enabled(gate_hw);
+}
+
+static int clk_sdmmc_mux_enable(struct clk_hw *hw)
+{
+ struct tegra_sdmmc_mux *sdmmc_mux = to_clk_sdmmc_mux(hw);
+ const struct clk_ops *gate_ops = sdmmc_mux->gate_ops;
+ struct clk_hw *gate_hw = &sdmmc_mux->gate.hw;
+
+ __clk_hw_set_clk(gate_hw, hw);
+
+ return gate_ops->enable(gate_hw);
+}
+
+static void clk_sdmmc_mux_disable(struct clk_hw *hw)
+{
+ struct tegra_sdmmc_mux *sdmmc_mux = to_clk_sdmmc_mux(hw);
+ const struct clk_ops *gate_ops = sdmmc_mux->gate_ops;
+ struct clk_hw *gate_hw = &sdmmc_mux->gate.hw;
+
+ gate_ops->disable(gate_hw);
+}
+
+const struct clk_ops tegra_clk_sdmmc_mux_ops = {
+ .get_parent = clk_sdmmc_mux_get_parent,
+ .set_parent = clk_sdmmc_mux_set_parent,
+ .determine_rate = clk_sdmmc_mux_determine_rate,
+ .recalc_rate = clk_sdmmc_mux_recalc_rate,
+ .set_rate = clk_sdmmc_mux_set_rate,
+ .is_enabled = clk_sdmmc_mux_is_enabled,
+ .enable = clk_sdmmc_mux_enable,
+ .disable = clk_sdmmc_mux_disable,
+};
+
+struct clk *tegra_clk_register_sdmmc_mux_div(const char *name,
+ void __iomem *clk_base, u32 offset, u32 clk_num, u8 div_flags,
+ unsigned long flags, void *lock)
+{
+ struct clk *clk;
+ struct clk_init_data init;
+ const struct tegra_clk_periph_regs *bank;
+ struct tegra_sdmmc_mux *sdmmc_mux;
+
+ init.ops = &tegra_clk_sdmmc_mux_ops;
+ init.name = name;
+ init.flags = flags;
+ init.parent_names = mux_sdmmc_parents;
+ init.num_parents = ARRAY_SIZE(mux_sdmmc_parents);
+
+ bank = get_reg_bank(clk_num);
+ if (!bank)
+ return ERR_PTR(-EINVAL);
+
+ sdmmc_mux = kzalloc(sizeof(*sdmmc_mux), GFP_KERNEL);
+ if (!sdmmc_mux)
+ return ERR_PTR(-ENOMEM);
+
+ /* Data in .init is copied by clk_register(), so stack variable OK */
+ sdmmc_mux->hw.init = &init;
+ sdmmc_mux->reg = clk_base + offset;
+ sdmmc_mux->lock = lock;
+ sdmmc_mux->gate.clk_base = clk_base;
+ sdmmc_mux->gate.regs = bank;
+ sdmmc_mux->gate.enable_refcnt = periph_clk_enb_refcnt;
+ sdmmc_mux->gate.clk_num = clk_num;
+ sdmmc_mux->gate.flags = TEGRA_PERIPH_ON_APB;
+ sdmmc_mux->div_flags = div_flags;
+ sdmmc_mux->gate_ops = &tegra_clk_periph_gate_ops;
+
+ clk = clk_register(NULL, &sdmmc_mux->hw);
+ if (IS_ERR(clk))
+ return clk;
+
+ sdmmc_mux->gate.hw.clk = clk;
+
+ return clk;
+}
+
diff --git a/drivers/clk/tegra/clk.h b/drivers/clk/tegra/clk.h
index f14e136..4c3d0f5 100644
--- a/drivers/clk/tegra/clk.h
+++ b/drivers/clk/tegra/clk.h
@@ -19,6 +19,7 @@

#include <linux/clk-provider.h>
#include <linux/clkdev.h>
+#include <linux/delay.h>

/**
* struct tegra_clk_sync_source - external clock source from codec
@@ -705,6 +706,32 @@ struct clk *tegra_clk_register_super_clk(const char *name,
const char * const *parent_names, u8 num_parents,
unsigned long flags, void __iomem *reg, u8 clk_super_flags,
spinlock_t *lock);
+
+/**
+ * struct tegra_sdmmc_mux - switch divider with Low Jitter inputs for SDMMC
+ *
+ * @hw: handle between common and hardware-specific interfaces
+ * @reg: register controlling mux and divider
+ * @flags: hardware-specific flags
+ * @lock: optional register lock
+ * @gate: gate clock
+ * @gate_ops: gate clock ops
+ */
+struct tegra_sdmmc_mux {
+ struct clk_hw hw;
+ void __iomem *reg;
+ spinlock_t *lock;
+ const struct clk_ops *gate_ops;
+ struct tegra_clk_periph_gate gate;
+ u8 div_flags;
+};
+
+#define to_clk_sdmmc_mux(_hw) container_of(_hw, struct tegra_sdmmc_mux, hw)
+
+struct clk *tegra_clk_register_sdmmc_mux_div(const char *name,
+ void __iomem *clk_base, u32 offset, u32 clk_num, u8 div_flags,
+ unsigned long flags, void *lock);
+
/**
* struct clk_init_table - clock initialization table
* @clk_id: clock id as mentioned in device tree bindings
--
2.7.4


2018-07-03 15:13:00

by Peter Geis

[permalink] [raw]
Subject: Re: [PATCH 1/3] clk: tegra: refactor 7.1 div calculation

Good Morning,

Just a heads up.
During compilation with your patches, I get the following warning:

In file included from ./arch/arm/include/asm/div64.h:127:0,
from ./include/linux/kernel.h:174,
from drivers/clk/tegra/div71.c:17:
drivers/clk/tegra/div71.c: In function ‘div71_get’:
./include/asm-generic/div64.h:222:28: warning: comparison of distinct
pointer types lacks a cast
(void)(((typeof((n)) *)0) == ((uint64_t *)0)); \
^
drivers/clk/tegra/div71.c:40:2: note: in expansion of macro ‘do_div’
do_div(divider_ux1, rate);
^~~~~~

Very Respectfully,
Peter Geis


On 07/03/2018 07:35 AM, Aapo Vienamo wrote:
> From: Peter De Schrijver <[email protected]>
>
> Move this to a separate file so it can be used to calculate the sdmmc
> clock dividers.
>
> Signed-off-by: Peter De-Schrijver <[email protected]>
> Signed-off-by: Aapo Vienamo <[email protected]>
> ---
> drivers/clk/tegra/Makefile | 1 +
> drivers/clk/tegra/clk-divider.c | 30 ++++--------------------
> drivers/clk/tegra/clk.h | 3 +++
> drivers/clk/tegra/div71.c | 51 +++++++++++++++++++++++++++++++++++++++++
> 4 files changed, 60 insertions(+), 25 deletions(-)
> create mode 100644 drivers/clk/tegra/div71.c
>
> diff --git a/drivers/clk/tegra/Makefile b/drivers/clk/tegra/Makefile
> index b716923..6d4f563 100644
> --- a/drivers/clk/tegra/Makefile
> +++ b/drivers/clk/tegra/Makefile
> @@ -24,3 +24,4 @@ obj-$(CONFIG_ARCH_TEGRA_132_SOC) += clk-tegra124.o
> obj-y += cvb.o
> obj-$(CONFIG_ARCH_TEGRA_210_SOC) += clk-tegra210.o
> obj-$(CONFIG_CLK_TEGRA_BPMP) += clk-bpmp.o
> +obj-y += div71.o
> diff --git a/drivers/clk/tegra/clk-divider.c b/drivers/clk/tegra/clk-divider.c
> index 16e0aee..ad87858 100644
> --- a/drivers/clk/tegra/clk-divider.c
> +++ b/drivers/clk/tegra/clk-divider.c
> @@ -32,35 +32,15 @@
> static int get_div(struct tegra_clk_frac_div *divider, unsigned long rate,
> unsigned long parent_rate)
> {
> - u64 divider_ux1 = parent_rate;
> - u8 flags = divider->flags;
> - int mul;
> -
> - if (!rate)
> - return 0;
> -
> - mul = get_mul(divider);
> -
> - if (!(flags & TEGRA_DIVIDER_INT))
> - divider_ux1 *= mul;
> -
> - if (flags & TEGRA_DIVIDER_ROUND_UP)
> - divider_ux1 += rate - 1;
> -
> - do_div(divider_ux1, rate);
> -
> - if (flags & TEGRA_DIVIDER_INT)
> - divider_ux1 *= mul;
> + int div;
>
> - divider_ux1 -= mul;
> + div = div71_get(rate, parent_rate, divider->width, divider->frac_width,
> + divider->flags);
>
> - if ((s64)divider_ux1 < 0)
> + if (div < 0)
> return 0;
>
> - if (divider_ux1 > get_max_div(divider))
> - return get_max_div(divider);
> -
> - return divider_ux1;
> + return div;
> }
>
> static unsigned long clk_frac_div_recalc_rate(struct clk_hw *hw,
> diff --git a/drivers/clk/tegra/clk.h b/drivers/clk/tegra/clk.h
> index e1f8846..f14e136 100644
> --- a/drivers/clk/tegra/clk.h
> +++ b/drivers/clk/tegra/clk.h
> @@ -811,6 +811,9 @@ extern tegra_clk_apply_init_table_func tegra_clk_apply_init_table;
> int tegra_pll_wait_for_lock(struct tegra_clk_pll *pll);
> u16 tegra_pll_get_fixed_mdiv(struct clk_hw *hw, unsigned long input_rate);
> int tegra_pll_p_div_to_hw(struct tegra_clk_pll *pll, u8 p_div);
> +int div71_get(unsigned long rate, unsigned parent_rate, u8 width,
> + u8 frac_width, u8 flags);
> +
>
> /* Combined read fence with delay */
> #define fence_udelay(delay, reg) \
> diff --git a/drivers/clk/tegra/div71.c b/drivers/clk/tegra/div71.c
> new file mode 100644
> index 0000000..27b3846
> --- /dev/null
> +++ b/drivers/clk/tegra/div71.c
> @@ -0,0 +1,51 @@
> +/*
> + * Copyright (c) 2018, NVIDIA CORPORATION. All rights reserved.
> + *
> + * This program is free software; you can redistribute it and/or modify it
> + * under the terms and conditions of the GNU General Public License,
> + * version 2, as published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope it will be useful, but WITHOUT
> + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
> + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
> + * more details.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program. If not, see <http://www.gnu.org/licenses/>.
> + */
> +
> +#include <linux/kernel.h>
> +
> +#include "clk.h"
> +
> +#define div_mask(w) ((1 << (w)) - 1)
> +
> +int div71_get(unsigned long rate, unsigned parent_rate, u8 width,
> + u8 frac_width, u8 flags)
> +{
> + s64 divider_ux1 = parent_rate;
> + int mul;
> +
> + if (!rate)
> + return 0;
> +
> + mul = 1 << frac_width;
> +
> + if (!(flags & TEGRA_DIVIDER_INT))
> + divider_ux1 *= mul;
> +
> + if (flags & TEGRA_DIVIDER_ROUND_UP)
> + divider_ux1 += rate - 1;
> +
> + do_div(divider_ux1, rate);
> +
> + if (flags & TEGRA_DIVIDER_INT)
> + divider_ux1 *= mul;
> +
> + divider_ux1 -= mul;
> +
> + if (divider_ux1 > div_mask(width))
> + return div_mask(width);
> +
> + return divider_ux1;
> +}
>

2018-07-03 15:32:27

by kernel test robot

[permalink] [raw]
Subject: Re: [PATCH 1/3] clk: tegra: refactor 7.1 div calculation

Hi Peter,

I love your patch! Perhaps something to improve:

[auto build test WARNING on tegra/for-next]
[also build test WARNING on v4.18-rc3 next-20180703]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url: https://github.com/0day-ci/linux/commits/Aapo-Vienamo/clk-tegra-refactor-7-1-div-calculation/20180703-205606
base: https://git.kernel.org/pub/scm/linux/kernel/git/tegra/linux.git for-next
config: arm-allmodconfig (attached as .config)
compiler: arm-linux-gnueabi-gcc (Debian 7.2.0-11) 7.2.0
reproduce:
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# save the attached .config to linux build tree
GCC_VERSION=7.2.0 make.cross ARCH=arm

All warnings (new ones prefixed by >>):

In file included from arch/arm/include/asm/div64.h:127:0,
from include/linux/kernel.h:174,
from drivers/clk/tegra/div71.c:17:
drivers/clk/tegra/div71.c: In function 'div71_get':
include/asm-generic/div64.h:222:28: warning: comparison of distinct pointer types lacks a cast
(void)(((typeof((n)) *)0) == ((uint64_t *)0)); \
^
>> drivers/clk/tegra/div71.c:40:2: note: in expansion of macro 'do_div'
do_div(divider_ux1, rate);
^~~~~~

vim +/do_div +40 drivers/clk/tegra/div71.c

> 17 #include <linux/kernel.h>
18
19 #include "clk.h"
20
21 #define div_mask(w) ((1 << (w)) - 1)
22
23 int div71_get(unsigned long rate, unsigned parent_rate, u8 width,
24 u8 frac_width, u8 flags)
25 {
26 s64 divider_ux1 = parent_rate;
27 int mul;
28
29 if (!rate)
30 return 0;
31
32 mul = 1 << frac_width;
33
34 if (!(flags & TEGRA_DIVIDER_INT))
35 divider_ux1 *= mul;
36
37 if (flags & TEGRA_DIVIDER_ROUND_UP)
38 divider_ux1 += rate - 1;
39
> 40 do_div(divider_ux1, rate);

---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation


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2018-07-04 07:58:04

by Aapo Vienamo

[permalink] [raw]
Subject: Re: [PATCH 1/3] clk: tegra: refactor 7.1 div calculation

On Tue, 3 Jul 2018 11:10:21 -0400
Peter Geis <[email protected]> wrote:

> Good Morning,
>
> Just a heads up.
> During compilation with your patches, I get the following warning:
>
> In file included from ./arch/arm/include/asm/div64.h:127:0,
> from ./include/linux/kernel.h:174,
> from drivers/clk/tegra/div71.c:17:
> drivers/clk/tegra/div71.c: In function ‘div71_get’:
> ./include/asm-generic/div64.h:222:28: warning: comparison of distinct
> pointer types lacks a cast
> (void)(((typeof((n)) *)0) == ((uint64_t *)0)); \
> ^
> drivers/clk/tegra/div71.c:40:2: note: in expansion of macro ‘do_div’
> do_div(divider_ux1, rate);
> ^~~~~~
>
> Very Respectfully,
> Peter Geis
>

That's indeed true. Looks like this warning is produced only on 32-bit
arm as it uses a different variant of the do_div macro than arm64.

Thanks,
-Aapo

2018-07-06 17:12:24

by Stephen Boyd

[permalink] [raw]
Subject: Re: [PATCH 1/3] clk: tegra: refactor 7.1 div calculation

Quoting Aapo Vienamo (2018-07-04 00:51:48)
> On Tue, 3 Jul 2018 11:10:21 -0400
> Peter Geis <[email protected]> wrote:
>
> > Good Morning,
> >
> > Just a heads up.
> > During compilation with your patches, I get the following warning:
> >
> > In file included from ./arch/arm/include/asm/div64.h:127:0,
> > from ./include/linux/kernel.h:174,
> > from drivers/clk/tegra/div71.c:17:
> > drivers/clk/tegra/div71.c: In function ‘div71_get’:
> > ./include/asm-generic/div64.h:222:28: warning: comparison of distinct
> > pointer types lacks a cast
> > (void)(((typeof((n)) *)0) == ((uint64_t *)0)); \
> > ^
> > drivers/clk/tegra/div71.c:40:2: note: in expansion of macro ‘do_div’
> > do_div(divider_ux1, rate);
> > ^~~~~~
> >
> > Very Respectfully,
> > Peter Geis
> >
>
> That's indeed true. Looks like this warning is produced only on 32-bit
> arm as it uses a different variant of the do_div macro than arm64.
>

divider_ux1 is an s64, but the generic do_div() macro is checking to
make sure that's compatible with a u64, and it isn't. Maybe you should
use a function like div64_long()?