clk: meson: gxbb: remove the "cpu_clk" from the GXBB and GXL driver

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@googlemail.com>
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>

diff --git a/drivers/clk/meson/gxbb.c b/drivers/clk/meson/gxbb.c
index ad5f027..7cf88ca 100644 (file)
--- 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 };
 
@@ -1045,7 +1020,6 @@ 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,
@@ -1165,7 +1139,6 @@ 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,
@@ -1430,7 +1403,6 @@ struct clkc_data {
        unsigned int clk_dividers_count;
        struct meson_clk_audio_divider *const *clk_audio_dividers;
        unsigned int clk_audio_dividers_count;
-       struct meson_clk_cpu *cpu_clk;
        struct clk_hw_onecell_data *hw_onecell_data;
 };
 
@@ -1447,7 +1419,6 @@ static const struct clkc_data gxbb_clkc_data = {
        .clk_dividers_count = ARRAY_SIZE(gxbb_clk_dividers),
        .clk_audio_dividers = gxbb_audio_dividers,
        .clk_audio_dividers_count = ARRAY_SIZE(gxbb_audio_dividers),
-       .cpu_clk = &gxbb_cpu_clk,
        .hw_onecell_data = &gxbb_hw_onecell_data,
 };
 
@@ -1464,7 +1435,6 @@ static const struct clkc_data gxl_clkc_data = {
        .clk_dividers_count = ARRAY_SIZE(gxbb_clk_dividers),
        .clk_audio_dividers = gxbb_audio_dividers,
        .clk_audio_dividers_count = ARRAY_SIZE(gxbb_audio_dividers),
-       .cpu_clk = &gxbb_cpu_clk,
        .hw_onecell_data = &gxl_hw_onecell_data,
 };
 
@@ -1479,8 +1449,6 @@ 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);
@@ -1502,9 +1470,6 @@ 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 +
@@ -1538,29 +1503,6 @@ 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 4d04f4a..70f029a 100644 (file)
--- 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 */