[PATCH v5 08/21] clk: thead: Add support for custom ops in CCU_GATE_CLK_OPS macro

Michal Wilczynski
2025-02-19T14:03:02Z

The IMG Rogue GPU requires three clocks: core, sys, and mem [1]. On the
T-HEAD TH1520 SoC, the mem clock gate is marked as "Reserved" in the
hardware manual (section 4.4.2.6.1) [2] and cannot be configured.

Add a new CCU_GATE_CLK_OPS macro that allows specifying custom clock
operations. This enables us to use nop operations for the mem clock,
preventing the driver from attempting to enable/disable this reserved
clock gate.

Link: https://lore.kernel.org/all/2fe3d93f-62ac-4439-ac17-d81137f6410a@imgtec.com [1]
Link: https://openbeagle.org/beaglev-ahead/beaglev-ahead/-/blob/main/docs/TH1520%20System%20User%20Manual.pdf [2]

Signed-off-by: Michal Wilczynski <m.wilczynski@samsung.com>
---
drivers/clk/thead/clk-th1520-ap.c | 26 ++++++++++++++++++++++++++
1 file changed, 26 insertions(+)

diff --git a/drivers/clk/thead/clk-th1520-ap.c b/drivers/clk/thead/clk-th1520-ap.c
index 57972589f120..ea96d007aecd 100644
--- a/drivers/clk/thead/clk-th1520-ap.c
+++ b/drivers/clk/thead/clk-th1520-ap.c
@@ -89,6 +89,21 @@ struct ccu_pll {
} \
}

+#define CCU_GATE_CLK_OPS(_clkid, _struct, _name, _parent, _reg, _gate, _flags, \
+ _clk_ops) \
+ struct ccu_gate _struct = { \
+ .enable = _gate, \
+ .common = { \
+ .clkid = _clkid, \
+ .cfg0 = _reg, \
+ .hw.init = CLK_HW_INIT_PARENTS_DATA( \
+ _name, \
+ _parent, \
+ &_clk_ops, \
+ _flags), \
+ } \
+ }
+
static inline struct ccu_common *hw_to_ccu_common(struct clk_hw *hw)
{
return container_of(hw, struct ccu_common, hw);
@@ -847,6 +862,11 @@ static CCU_GATE(CLK_SRAM1, sram1_clk, "sram1", axi_aclk_pd, 0x20c, BIT(3), 0);
static CCU_GATE(CLK_SRAM2, sram2_clk, "sram2", axi_aclk_pd, 0x20c, BIT(2), 0);
static CCU_GATE(CLK_SRAM3, sram3_clk, "sram3", axi_aclk_pd, 0x20c, BIT(1), 0);

+static const struct clk_ops clk_nop_ops = {};
+
+static CCU_GATE_CLK_OPS(CLK_GPU_MEM, gpu_mem_clk, "gpu-mem-clk",
+ video_pll_clk_pd, 0x0, BIT(2), 0, clk_nop_ops);
+
static CCU_GATE(CLK_AXI4_VO_ACLK, axi4_vo_aclk, "axi4-vo-aclk",
video_pll_clk_pd, 0x0, BIT(0), 0);
static CCU_GATE(CLK_GPU_CORE, gpu_core_clk, "gpu-core-clk", video_pll_clk_pd,
@@ -1205,6 +1225,12 @@ static int th1520_clk_probe(struct platform_device *pdev)
ret = devm_clk_hw_register(dev, &emmc_sdio_ref_clk.hw);
if (ret)
return ret;
+ } else if (plat_data == &th1520_vo_platdata) {
+ ret = devm_clk_hw_register(dev, &gpu_mem_clk.common.hw);
+ if (ret)
+ return ret;
+ gpu_mem_clk.common.map = map;
+ priv->hws[CLK_GPU_MEM] = &gpu_mem_clk.common.hw;
}

ret = devm_of_clk_add_hw_provider(dev, of_clk_hw_onecell_get, priv);
--
2.34.1