drivers: clk: Add memory clock driver for Intel N5X device
Add memory clock manager driver for N5X. Provides memory clock
initialization and enable functions.
Signed-off-by: Siew Chin Lim <elly.siew.chin.lim@intel.com>
diff --git a/drivers/clk/altera/clk-mem-n5x.c b/drivers/clk/altera/clk-mem-n5x.c
new file mode 100644
index 0000000..ca44998
--- /dev/null
+++ b/drivers/clk/altera/clk-mem-n5x.c
@@ -0,0 +1,136 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2020-2021 Intel Corporation <www.intel.com>
+ */
+
+#include <common.h>
+#include <asm/arch/clock_manager.h>
+#include <asm/global_data.h>
+#include <asm/io.h>
+#include "clk-mem-n5x.h"
+#include <clk-uclass.h>
+#include <dm.h>
+#include <dm/lists.h>
+#include <dm/util.h>
+#include <dt-bindings/clock/n5x-clock.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+struct socfpga_mem_clk_plat {
+ void __iomem *regs;
+};
+
+void clk_mem_wait_for_lock(struct socfpga_mem_clk_plat *plat, u32 mask)
+{
+ u32 inter_val;
+ u32 retry = 0;
+
+ do {
+ inter_val = CM_REG_READL(plat, MEMCLKMGR_STAT) & mask;
+
+ /* Wait for stable lock */
+ if (inter_val == mask)
+ retry++;
+ else
+ retry = 0;
+
+ if (retry >= 10)
+ return;
+ } while (1);
+}
+
+/*
+ * function to write the bypass register which requires a poll of the
+ * busy bit
+ */
+void clk_mem_write_bypass_mempll(struct socfpga_mem_clk_plat *plat, u32 val)
+{
+ CM_REG_WRITEL(plat, val, MEMCLKMGR_MEMPLL_BYPASS);
+}
+
+/*
+ * Setup clocks while making no assumptions about previous state of the clocks.
+ */
+static void clk_mem_basic_init(struct udevice *dev,
+ const struct cm_config * const cfg)
+{
+ struct socfpga_mem_clk_plat *plat = dev_get_plat(dev);
+
+ if (!cfg)
+ return;
+
+ /* Put PLLs in bypass */
+ clk_mem_write_bypass_mempll(plat, MEMCLKMGR_BYPASS_MEMPLL_ALL);
+
+ /* Put PLLs in Reset */
+ CM_REG_SETBITS(plat, MEMCLKMGR_MEMPLL_PLLCTRL,
+ MEMCLKMGR_PLLCTRL_BYPASS_MASK);
+
+ /* setup mem PLL */
+ CM_REG_WRITEL(plat, cfg->mem_memdiv, MEMCLKMGR_MEMPLL_MEMDIV);
+ CM_REG_WRITEL(plat, cfg->mem_pllglob, MEMCLKMGR_MEMPLL_PLLGLOB);
+ CM_REG_WRITEL(plat, cfg->mem_plldiv, MEMCLKMGR_MEMPLL_PLLDIV);
+ CM_REG_WRITEL(plat, cfg->mem_plloutdiv, MEMCLKMGR_MEMPLL_PLLOUTDIV);
+
+ /* Take PLL out of reset and power up */
+ CM_REG_CLRBITS(plat, MEMCLKMGR_MEMPLL_PLLCTRL,
+ MEMCLKMGR_PLLCTRL_BYPASS_MASK);
+}
+
+static int socfpga_mem_clk_enable(struct clk *clk)
+{
+ const struct cm_config *cm_default_cfg = cm_get_default_config();
+ struct socfpga_mem_clk_plat *plat = dev_get_plat(clk->dev);
+
+ clk_mem_basic_init(clk->dev, cm_default_cfg);
+
+ clk_mem_wait_for_lock(plat, MEMCLKMGR_STAT_ALLPLL_LOCKED_MASK);
+
+ CM_REG_WRITEL(plat, CM_REG_READL(plat, MEMCLKMGR_MEMPLL_PLLGLOB) |
+ MEMCLKMGR_PLLGLOB_CLR_LOSTLOCK_BYPASS_MASK,
+ MEMCLKMGR_MEMPLL_PLLGLOB);
+
+ /* Take all PLLs out of bypass */
+ clk_mem_write_bypass_mempll(plat, 0);
+
+ /* Clear the loss of lock bits (write 1 to clear) */
+ CM_REG_CLRBITS(plat, MEMCLKMGR_INTRCLR,
+ MEMCLKMGR_INTER_MEMPLLLOST_MASK);
+
+ /* Take all ping pong counters out of reset */
+ CM_REG_CLRBITS(plat, MEMCLKMGR_MEMPLL_EXTCNTRST,
+ MEMCLKMGR_EXTCNTRST_ALLCNTRST);
+
+ return 0;
+}
+
+static int socfpga_mem_clk_of_to_plat(struct udevice *dev)
+{
+ struct socfpga_mem_clk_plat *plat = dev_get_plat(dev);
+ fdt_addr_t addr;
+
+ addr = devfdt_get_addr(dev);
+ if (addr == FDT_ADDR_T_NONE)
+ return -EINVAL;
+ plat->regs = (void __iomem *)addr;
+
+ return 0;
+}
+
+static struct clk_ops socfpga_mem_clk_ops = {
+ .enable = socfpga_mem_clk_enable
+};
+
+static const struct udevice_id socfpga_mem_clk_match[] = {
+ { .compatible = "intel,n5x-mem-clkmgr" },
+ {}
+};
+
+U_BOOT_DRIVER(socfpga_n5x_mem_clk) = {
+ .name = "mem-clk-n5x",
+ .id = UCLASS_CLK,
+ .of_match = socfpga_mem_clk_match,
+ .ops = &socfpga_mem_clk_ops,
+ .of_to_plat = socfpga_mem_clk_of_to_plat,
+ .plat_auto = sizeof(struct socfpga_mem_clk_plat),
+};