[PATCH v2 2/2] clk: meson: gxbb: remove the "cpu_clk" from the GXBB and GXL driver
Martin Blumenstingl
martin.blumenstingl at googlemail.com
Thu May 4 11:19:20 PDT 2017
It seems that the "cpu_clk" was carried over from the meson8b clock
controller driver. On Meson GX (GXBB/GXL/GXM) the registers which are
used by the cpu_clk have a different purpose (in other words: they don't
control the CPU clock anymore). HHI_SYS_CPU_CLK_CNTL1 bits 31:24 are
reserved according to the public S905 datasheet, while bit 23 is the
"A53_trace_clk_DIS" gate (which according to the datasheet should only
be used in case a silicon bug is discovered) and bits 22:20 are a
divider (A53_trace_clk). The meson clk-cpu code however expects that
bits 28:20 are reserved for a divider (according to the public S805
datasheet this "SCALE_DIV: This value represents an N+1 divider of the
input clock.").
The CPU clock on Meson GX SoCs is provided by the SCPI DVFS clock
driver instead. Two examples from a Meson GXL S905X SoC:
- vcpu (SCPI DVFS clock 0) rate: 1000000000 / cpu_clk rate: 708000000
- vcpu (SCPI DVFS clock 0) rate: 1512000000 / cpu_clk rate: 708000000
Unfortunately the CLKID_CPUCLK was already exported (but is currently
not used) to DT. Due to the removal of this clock definition there is
now a hole in the clk_hw_onecell_data (which is not a problem because
this case is already handled in gxbb_clkc_probe).
Signed-off-by: Martin Blumenstingl <martin.blumenstingl at googlemail.com>
---
drivers/clk/meson/gxbb.c | 64 +++---------------------------------------------
drivers/clk/meson/gxbb.h | 2 +-
2 files changed, 4 insertions(+), 62 deletions(-)
diff --git a/drivers/clk/meson/gxbb.c b/drivers/clk/meson/gxbb.c
index 75197664a7ee..25d05fc2d045 100644
--- a/drivers/clk/meson/gxbb.c
+++ b/drivers/clk/meson/gxbb.c
@@ -278,20 +278,6 @@ static const struct pll_rate_table gxl_gp0_pll_rate_table[] = {
{ /* sentinel */ },
};
-static const struct clk_div_table cpu_div_table[] = {
- { .val = 1, .div = 1 },
- { .val = 2, .div = 2 },
- { .val = 3, .div = 3 },
- { .val = 2, .div = 4 },
- { .val = 3, .div = 6 },
- { .val = 4, .div = 8 },
- { .val = 5, .div = 10 },
- { .val = 6, .div = 12 },
- { .val = 7, .div = 14 },
- { .val = 8, .div = 16 },
- { /* sentinel */ },
-};
-
static struct meson_clk_pll gxbb_fixed_pll = {
.m = {
.reg_off = HHI_MPLL_CNTL,
@@ -612,21 +598,10 @@ static struct meson_clk_mpll gxbb_mpll2 = {
};
/*
- * FIXME cpu clocks and the legacy composite clocks (e.g. clk81) are both PLL
- * post-dividers and should be modeled with their respective PLLs via the
- * forthcoming coordinated clock rates feature
+ * FIXME The legacy composite clocks (e.g. clk81) are both PLL post-dividers
+ * and should be modeled with their respective PLLs via the forthcoming
+ * coordinated clock rates feature
*/
-static struct meson_clk_cpu gxbb_cpu_clk = {
- .reg_off = HHI_SYS_CPU_CLK_CNTL1,
- .div_table = cpu_div_table,
- .clk_nb.notifier_call = meson_clk_cpu_notifier_cb,
- .hw.init = &(struct clk_init_data){
- .name = "cpu_clk",
- .ops = &meson_clk_cpu_ops,
- .parent_names = (const char *[]){ "sys_pll" },
- .num_parents = 1,
- },
-};
static u32 mux_table_clk81[] = { 6, 5, 7 };
@@ -939,7 +914,6 @@ static MESON_GATE(gxbb_ao_i2c, HHI_GCLK_AO, 4);
static struct clk_hw_onecell_data gxbb_hw_onecell_data = {
.hws = {
[CLKID_SYS_PLL] = &gxbb_sys_pll.hw,
- [CLKID_CPUCLK] = &gxbb_cpu_clk.hw,
[CLKID_HDMI_PLL] = &gxbb_hdmi_pll.hw,
[CLKID_FIXED_PLL] = &gxbb_fixed_pll.hw,
[CLKID_FCLK_DIV2] = &gxbb_fclk_div2.hw,
@@ -1052,7 +1026,6 @@ static struct clk_hw_onecell_data gxbb_hw_onecell_data = {
static struct clk_hw_onecell_data gxl_hw_onecell_data = {
.hws = {
[CLKID_SYS_PLL] = &gxbb_sys_pll.hw,
- [CLKID_CPUCLK] = &gxbb_cpu_clk.hw,
[CLKID_HDMI_PLL] = &gxbb_hdmi_pll.hw,
[CLKID_FIXED_PLL] = &gxbb_fixed_pll.hw,
[CLKID_FCLK_DIV2] = &gxbb_fclk_div2.hw,
@@ -1298,7 +1271,6 @@ struct clkc_data {
unsigned int clk_muxes_count;
struct clk_divider *const *clk_dividers;
unsigned int clk_dividers_count;
- struct meson_clk_cpu *cpu_clk;
struct clk_hw_onecell_data *hw_onecell_data;
};
@@ -1313,7 +1285,6 @@ static const struct clkc_data gxbb_clkc_data = {
.clk_muxes_count = ARRAY_SIZE(gxbb_clk_muxes),
.clk_dividers = gxbb_clk_dividers,
.clk_dividers_count = ARRAY_SIZE(gxbb_clk_dividers),
- .cpu_clk = &gxbb_cpu_clk,
.hw_onecell_data = &gxbb_hw_onecell_data,
};
@@ -1328,7 +1299,6 @@ static const struct clkc_data gxl_clkc_data = {
.clk_muxes_count = ARRAY_SIZE(gxbb_clk_muxes),
.clk_dividers = gxbb_clk_dividers,
.clk_dividers_count = ARRAY_SIZE(gxbb_clk_dividers),
- .cpu_clk = &gxbb_cpu_clk,
.hw_onecell_data = &gxl_hw_onecell_data,
};
@@ -1343,8 +1313,6 @@ static int gxbb_clkc_probe(struct platform_device *pdev)
const struct clkc_data *clkc_data;
void __iomem *clk_base;
int ret, clkid, i;
- struct clk_hw *parent_hw;
- struct clk *parent_clk;
struct device *dev = &pdev->dev;
clkc_data = of_device_get_match_data(&pdev->dev);
@@ -1366,9 +1334,6 @@ static int gxbb_clkc_probe(struct platform_device *pdev)
for (i = 0; i < clkc_data->clk_mplls_count; i++)
clkc_data->clk_mplls[i]->base = clk_base;
- /* Populate the base address for CPU clk */
- clkc_data->cpu_clk->base = clk_base;
-
/* Populate base address for gates */
for (i = 0; i < clkc_data->clk_gates_count; i++)
clkc_data->clk_gates[i]->reg = clk_base +
@@ -1394,29 +1359,6 @@ static int gxbb_clkc_probe(struct platform_device *pdev)
goto iounmap;
}
- /*
- * Register CPU clk notifier
- *
- * FIXME this is wrong for a lot of reasons. First, the muxes should be
- * struct clk_hw objects. Second, we shouldn't program the muxes in
- * notifier handlers. The tricky programming sequence will be handled
- * by the forthcoming coordinated clock rates mechanism once that
- * feature is released.
- *
- * Furthermore, looking up the parent this way is terrible. At some
- * point we will stop allocating a default struct clk when registering
- * a new clk_hw, and this hack will no longer work. Releasing the ccr
- * feature before that time solves the problem :-)
- */
- parent_hw = clk_hw_get_parent(&clkc_data->cpu_clk->hw);
- parent_clk = parent_hw->clk;
- ret = clk_notifier_register(parent_clk, &clkc_data->cpu_clk->clk_nb);
- if (ret) {
- pr_err("%s: failed to register clock notifier for cpu_clk\n",
- __func__);
- goto iounmap;
- }
-
return of_clk_add_hw_provider(dev->of_node, of_clk_hw_onecell_get,
clkc_data->hw_onecell_data);
diff --git a/drivers/clk/meson/gxbb.h b/drivers/clk/meson/gxbb.h
index c15bbce8c585..e5ed71e6353a 100644
--- a/drivers/clk/meson/gxbb.h
+++ b/drivers/clk/meson/gxbb.h
@@ -171,7 +171,7 @@
* to be exposed to client nodes in DT: include/dt-bindings/clock/gxbb-clkc.h
*/
#define CLKID_SYS_PLL 0
-#define CLKID_CPUCLK 1
+/* ID 1 is unused (it was used by the non-existing CLKID_CPUCLK before) */
/* CLKID_HDMI_PLL */
#define CLKID_FIXED_PLL 3
/* CLKID_FCLK_DIV2 */
--
2.12.2
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