[PATCH] clk: mvebu: cp110: Fix clock tree representation

From: Gregory CLEMENT
Date: Wed Feb 28 2018 - 09:08:33 EST


Thanks to new documentation, we have a better view of the clock tree.
There were few mistakes in the first version of this driver, the main one
being the parental link between the clocks. Actually the tree is more
flat that we though. Most of the IP blocks require two clocks: one for
the IP itself and one for accessing the registers, and unlike what we
wrote there is no link between these two clocks.

The other mistakes were about the name of the clocks: the root clock is
not the Audio PLL but the PLL0, and what we called the EIP clock is named
the x2 Core clock and is used by other IP block than the EIP ones.

Signed-off-by: Gregory CLEMENT <gregory.clement@xxxxxxxxxxx>
---
drivers/clk/mvebu/cp110-system-controller.c | 94 ++++++++++++-----------------
1 file changed, 39 insertions(+), 55 deletions(-)

diff --git a/drivers/clk/mvebu/cp110-system-controller.c b/drivers/clk/mvebu/cp110-system-controller.c
index ca9a0a536174..75bf7b8f282f 100644
--- a/drivers/clk/mvebu/cp110-system-controller.c
+++ b/drivers/clk/mvebu/cp110-system-controller.c
@@ -13,18 +13,17 @@
/*
* CP110 has 6 core clocks:
*
- * - APLL (1 Ghz)
- * - PPv2 core (1/3 APLL)
- * - EIP (1/2 APLL)
- * - Core (1/2 EIP)
- * - SDIO (2/5 APLL)
+ * - PLL0 (1 Ghz)
+ * - PPv2 core (1/3 PLL0)
+ * - x2 Core (1/2 PLL0)
+ * - Core (1/2 x2 Core)
+ * - SDIO (2/5 PLL0)
*
* - NAND clock, which is either:
* - Equal to SDIO clock
- * - 2/5 APLL
+ * - 2/5 PLL0
*
- * CP110 has 32 gatable clocks, for the various peripherals in the
- * IP. They have fairly complicated parent/child relationships.
+ * CP110 has 32 gatable clocks, for the various peripherals in the IP.
*/

#define pr_fmt(fmt) "cp110-system-controller: " fmt
@@ -53,9 +52,9 @@ enum {
#define CP110_CLK_NUM \
(CP110_MAX_CORE_CLOCKS + CP110_MAX_GATABLE_CLOCKS)

-#define CP110_CORE_APLL 0
+#define CP110_CORE_PLL0 0
#define CP110_CORE_PPV2 1
-#define CP110_CORE_EIP 2
+#define CP110_CORE_X2CORE 2
#define CP110_CORE_CORE 3
#define CP110_CORE_NAND 4
#define CP110_CORE_SDIO 5
@@ -237,7 +236,7 @@ static int cp110_syscon_common_probe(struct platform_device *pdev,
struct regmap *regmap;
struct device *dev = &pdev->dev;
struct device_node *np = dev->of_node;
- const char *ppv2_name, *apll_name, *core_name, *eip_name, *nand_name,
+ const char *ppv2_name, *pll0_name, *core_name, *x2core_name, *nand_name,
*sdio_name;
struct clk_hw_onecell_data *cp110_clk_data;
struct clk_hw *hw, **cp110_clks;
@@ -263,20 +262,20 @@ static int cp110_syscon_common_probe(struct platform_device *pdev,
cp110_clks = cp110_clk_data->hws;
cp110_clk_data->num = CP110_CLK_NUM;

- /* Register the APLL which is the root of the hw tree */
- apll_name = cp110_unique_name(dev, syscon_node, "apll");
- hw = clk_hw_register_fixed_rate(NULL, apll_name, NULL, 0,
+ /* Register the PLL0 which is the root of the hw tree */
+ pll0_name = cp110_unique_name(dev, syscon_node, "pll0");
+ hw = clk_hw_register_fixed_rate(NULL, pll0_name, NULL, 0,
1000 * 1000 * 1000);
if (IS_ERR(hw)) {
ret = PTR_ERR(hw);
- goto fail_apll;
+ goto fail_pll0;
}

- cp110_clks[CP110_CORE_APLL] = hw;
+ cp110_clks[CP110_CORE_PLL0] = hw;

- /* PPv2 is APLL/3 */
+ /* PPv2 is PLL0/3 */
ppv2_name = cp110_unique_name(dev, syscon_node, "ppv2-core");
- hw = clk_hw_register_fixed_factor(NULL, ppv2_name, apll_name, 0, 1, 3);
+ hw = clk_hw_register_fixed_factor(NULL, ppv2_name, pll0_name, 0, 1, 3);
if (IS_ERR(hw)) {
ret = PTR_ERR(hw);
goto fail_ppv2;
@@ -284,30 +283,32 @@ static int cp110_syscon_common_probe(struct platform_device *pdev,

cp110_clks[CP110_CORE_PPV2] = hw;

- /* EIP clock is APLL/2 */
- eip_name = cp110_unique_name(dev, syscon_node, "eip");
- hw = clk_hw_register_fixed_factor(NULL, eip_name, apll_name, 0, 1, 2);
+ /* X2CORE clock is PLL0/2 */
+ x2core_name = cp110_unique_name(dev, syscon_node, "x2core");
+ hw = clk_hw_register_fixed_factor(NULL, x2core_name, pll0_name,
+ 0, 1, 2);
if (IS_ERR(hw)) {
ret = PTR_ERR(hw);
goto fail_eip;
}

- cp110_clks[CP110_CORE_EIP] = hw;
+ cp110_clks[CP110_CORE_X2CORE] = hw;

- /* Core clock is EIP/2 */
+ /* Core clock is X2CORE/2 */
core_name = cp110_unique_name(dev, syscon_node, "core");
- hw = clk_hw_register_fixed_factor(NULL, core_name, eip_name, 0, 1, 2);
+ hw = clk_hw_register_fixed_factor(NULL, core_name, x2core_name,
+ 0, 1, 2);
if (IS_ERR(hw)) {
ret = PTR_ERR(hw);
goto fail_core;
}

cp110_clks[CP110_CORE_CORE] = hw;
- /* NAND can be either APLL/2.5 or core clock */
+ /* NAND can be either PLL0/2.5 or core clock */
nand_name = cp110_unique_name(dev, syscon_node, "nand-core");
if (nand_clk_ctrl & NF_CLOCK_SEL_400_MASK)
hw = clk_hw_register_fixed_factor(NULL, nand_name,
- apll_name, 0, 2, 5);
+ pll0_name, 0, 2, 5);
else
hw = clk_hw_register_fixed_factor(NULL, nand_name,
core_name, 0, 1, 1);
@@ -318,10 +319,10 @@ static int cp110_syscon_common_probe(struct platform_device *pdev,

cp110_clks[CP110_CORE_NAND] = hw;

- /* SDIO clock is APLL/2.5 */
+ /* SDIO clock is PLL0/2.5 */
sdio_name = cp110_unique_name(dev, syscon_node, "sdio-core");
hw = clk_hw_register_fixed_factor(NULL, sdio_name,
- apll_name, 0, 2, 5);
+ pll0_name, 0, 2, 5);
if (IS_ERR(hw)) {
ret = PTR_ERR(hw);
goto fail_sdio;
@@ -341,40 +342,23 @@ static int cp110_syscon_common_probe(struct platform_device *pdev,
continue;

switch (i) {
- case CP110_GATE_AUDIO:
- case CP110_GATE_COMM_UNIT:
- case CP110_GATE_EIP150:
- case CP110_GATE_EIP197:
- case CP110_GATE_SLOW_IO:
- parent = gate_name[CP110_GATE_MAIN];
- break;
- case CP110_GATE_MG:
- parent = gate_name[CP110_GATE_MG_CORE];
- break;
case CP110_GATE_NAND:
parent = nand_name;
break;
+ case CP110_GATE_MG:
+ case CP110_GATE_GOP_DP:
case CP110_GATE_PPV2:
parent = ppv2_name;
break;
case CP110_GATE_SDIO:
parent = sdio_name;
break;
- case CP110_GATE_GOP_DP:
- parent = gate_name[CP110_GATE_SDMMC_GOP];
- break;
- case CP110_GATE_XOR1:
- case CP110_GATE_XOR0:
- case CP110_GATE_PCIE_X1_0:
- case CP110_GATE_PCIE_X1_1:
+ case CP110_GATE_MAIN:
+ case CP110_GATE_PCIE_XOR:
case CP110_GATE_PCIE_X4:
- parent = gate_name[CP110_GATE_PCIE_XOR];
- break;
- case CP110_GATE_SATA:
- case CP110_GATE_USB3H0:
- case CP110_GATE_USB3H1:
- case CP110_GATE_USB3DEV:
- parent = gate_name[CP110_GATE_SATA_USB];
+ case CP110_GATE_EIP150:
+ case CP110_GATE_EIP197:
+ parent = x2core_name;
break;
default:
parent = core_name;
@@ -413,12 +397,12 @@ static int cp110_syscon_common_probe(struct platform_device *pdev,
fail_nand:
clk_hw_unregister_fixed_factor(cp110_clks[CP110_CORE_CORE]);
fail_core:
- clk_hw_unregister_fixed_factor(cp110_clks[CP110_CORE_EIP]);
+ clk_hw_unregister_fixed_factor(cp110_clks[CP110_CORE_X2CORE]);
fail_eip:
clk_hw_unregister_fixed_factor(cp110_clks[CP110_CORE_PPV2]);
fail_ppv2:
- clk_hw_unregister_fixed_rate(cp110_clks[CP110_CORE_APLL]);
-fail_apll:
+ clk_hw_unregister_fixed_rate(cp110_clks[CP110_CORE_PLL0]);
+fail_pll0:
return ret;
}

--
2.16.1