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/Makefile b/drivers/clk/altera/Makefile
index 38cd730..33db092 100644 (file)
--- a/drivers/clk/altera/Makefile
+++ b/drivers/clk/altera/Makefile
@@ -6,3 +6,4 @@
 obj-$(CONFIG_TARGET_SOCFPGA_AGILEX) += clk-agilex.o
 obj-$(CONFIG_TARGET_SOCFPGA_ARRIA10) += clk-arria10.o
 obj-$(CONFIG_TARGET_SOCFPGA_N5X) += clk-n5x.o
+obj-$(CONFIG_TARGET_SOCFPGA_N5X) += clk-mem-n5x.o

diff --git a/drivers/clk/altera/clk-mem-n5x.c b/drivers/clk/altera/clk-mem-n5x.c
new file mode 100644 (file)
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),
+};

diff --git a/drivers/clk/altera/clk-mem-n5x.h b/drivers/clk/altera/clk-mem-n5x.h
new file mode 100644 (file)
index 0000000..d000ae2
--- /dev/null
+++ b/drivers/clk/altera/clk-mem-n5x.h
@@ -0,0 +1,84 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2020-2021 Intel Corporation <www.intel.com>
+ */
+
+#ifndef        _CLK_MEM_N5X_
+#define        _CLK_MEM_N5X_
+
+#ifndef __ASSEMBLY__
+#include <linux/bitops.h>
+#endif
+
+/* Clock Manager registers */
+#define MEMCLKMGR_STAT                                 4
+#define MEMCLKMGR_INTRGEN                              8
+#define MEMCLKMGR_INTRMSK                              0x0c
+#define MEMCLKMGR_INTRCLR                              0x10
+#define MEMCLKMGR_INTRSTS                              0x14
+#define MEMCLKMGR_INTRSTK                              0x18
+#define MEMCLKMGR_INTRRAW                              0x1c
+
+/* Memory Clock Manager PPL group registers */
+#define MEMCLKMGR_MEMPLL_EN                            0x20
+#define MEMCLKMGR_MEMPLL_ENS                           0x24
+#define MEMCLKMGR_MEMPLL_ENR                           0x28
+#define MEMCLKMGR_MEMPLL_BYPASS                                0x2c
+#define MEMCLKMGR_MEMPLL_BYPASSS                       0x30
+#define MEMCLKMGR_MEMPLL_BYPASSR                       0x34
+#define MEMCLKMGR_MEMPLL_MEMDIV                                0x38
+#define MEMCLKMGR_MEMPLL_PLLGLOB                       0x3c
+#define MEMCLKMGR_MEMPLL_PLLCTRL                       0x40
+#define MEMCLKMGR_MEMPLL_PLLDIV                                0x44
+#define MEMCLKMGR_MEMPLL_PLLOUTDIV                     0x48
+#define MEMCLKMGR_MEMPLL_EXTCNTRST                     0x4c
+
+#define MEMCLKMGR_CTRL_BOOTMODE                                BIT(0)
+
+#define MEMCLKMGR_STAT_MEMPLL_LOCKED                   BIT(8)
+
+#define MEMCLKMGR_STAT_ALLPLL_LOCKED_MASK              \
+       (MEMCLKMGR_STAT_MEMPLL_LOCKED)
+
+#define MEMCLKMGR_INTER_MEMPLLLOCKED_MASK              BIT(0)
+#define MEMCLKMGR_INTER_MEMPLLLOST_MASK                        BIT(2)
+
+#define MEMCLKMGR_BYPASS_MEMPLL_ALL                    0x1
+
+#define MEMCLKMGR_MEMDIV_MPFEDIV_OFFSET                        0
+#define MEMCLKMGR_MEMDIV_APBDIV_OFFSET                 4
+#define MEMCLKMGR_MEMDIV_DFICTRLDIV_OFFSET             8
+#define MEMCLKMGR_MEMDIV_DFIDIV_OFFSET                 12
+#define MEMCLKMGR_MEMDIV_DFICTRLDIV_MASK               BIT(0)
+#define MEMCLKMGR_MEMDIV_DIVIDER_MASK                  GENMASK(1, 0)
+
+#define MEMCLKMGR_PLLGLOB_PSRC_MASK                    GENMASK(17, 16)
+#define MEMCLKMGR_PLLGLOB_PSRC_OFFSET                  16
+#define MEMCLKMGR_PLLGLOB_LOSTLOCK_BYPASS_EN_MASK      BIT(28)
+#define MEMCLKMGR_PLLGLOB_CLR_LOSTLOCK_BYPASS_MASK     BIT(29)
+
+#define MEMCLKMGR_PSRC_EOSC1                           0
+#define MEMCLKMGR_PSRC_INTOSC                          1
+#define MEMCLKMGR_PSRC_F2S                             2
+
+#define MEMCLKMGR_PLLCTRL_BYPASS_MASK                  BIT(0)
+#define MEMCLKMGR_PLLCTRL_RST_N_MASK                   BIT(1)
+
+#define MEMCLKMGR_PLLDIV_DIVR_MASK                     GENMASK(5, 0)
+#define MEMCLKMGR_PLLDIV_DIVF_MASK                     GENMASK(16, 8)
+#define MEMCLKMGR_PLLDIV_DIVQ_MASK                     GENMASK(26, 24)
+#define MEMCLKMGR_PLLDIV_RANGE_MASK                    GENMASK(30, 28)
+
+#define MEMCLKMGR_PLLDIV_DIVR_OFFSET                   0
+#define MEMCLKMGR_PLLDIV_DIVF_OFFSET                   8
+#define MEMCLKMGR_PLLDIV_DIVQ_QDIV_OFFSET              24
+#define MEMCLKMGR_PLLDIV_RANGE_OFFSET                  28
+
+#define MEMCLKMGR_PLLOUTDIV_C0CNT_MASK                 GENMASK(4, 0)
+#define MEMCLKMGR_PLLOUTDIV_C0CNT_OFFSET               0
+
+#define MEMCLKMGR_EXTCNTRST_C0CNTRST                   BIT(7)
+#define MEMCLKMGR_EXTCNTRST_ALLCNTRST                  \
+       (MEMCLKMGR_EXTCNTRST_C0CNTRST)
+
+#endif /* _CLK_MEM_N5X_ */