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-rw-r--r--arch/arc/plat-hsdk/platform.c108
1 files changed, 108 insertions, 0 deletions
diff --git a/arch/arc/plat-hsdk/platform.c b/arch/arc/plat-hsdk/platform.c
new file mode 100644
index 000000000000..744e62e58788
--- /dev/null
+++ b/arch/arc/plat-hsdk/platform.c
@@ -0,0 +1,108 @@
+/*
+ * ARC HSDK Platform support code
+ *
+ * Copyright (C) 2017 Synopsys, Inc. (www.synopsys.com)
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/init.h>
+#include <linux/smp.h>
+#include <asm/arcregs.h>
+#include <asm/io.h>
+#include <asm/mach_desc.h>
+
+#define ARC_CCM_UNUSED_ADDR 0x60000000
+
+static void __init hsdk_init_per_cpu(unsigned int cpu)
+{
+ /*
+ * By default ICCM is mapped to 0x7z while this area is used for
+ * kernel virtual mappings, so move it to currently unused area.
+ */
+ if (cpuinfo_arc700[cpu].iccm.sz)
+ write_aux_reg(ARC_REG_AUX_ICCM, ARC_CCM_UNUSED_ADDR);
+
+ /*
+ * By default DCCM is mapped to 0x8z while this area is used by kernel,
+ * so move it to currently unused area.
+ */
+ if (cpuinfo_arc700[cpu].dccm.sz)
+ write_aux_reg(ARC_REG_AUX_DCCM, ARC_CCM_UNUSED_ADDR);
+}
+
+#define ARC_PERIPHERAL_BASE 0xf0000000
+#define CREG_BASE (ARC_PERIPHERAL_BASE + 0x1000)
+#define CREG_PAE (CREG_BASE + 0x180)
+#define CREG_PAE_UPDATE (CREG_BASE + 0x194)
+
+#define CREG_CORE_IF_CLK_DIV (CREG_BASE + 0x4B8)
+#define CREG_CORE_IF_CLK_DIV_2 0x1
+#define CGU_BASE ARC_PERIPHERAL_BASE
+#define CGU_PLL_STATUS (ARC_PERIPHERAL_BASE + 0x4)
+#define CGU_PLL_CTRL (ARC_PERIPHERAL_BASE + 0x0)
+#define CGU_PLL_STATUS_LOCK BIT(0)
+#define CGU_PLL_STATUS_ERR BIT(1)
+#define CGU_PLL_CTRL_1GHZ 0x3A10
+#define HSDK_PLL_LOCK_TIMEOUT 500
+
+#define HSDK_PLL_LOCKED() \
+ !!(ioread32((void __iomem *) CGU_PLL_STATUS) & CGU_PLL_STATUS_LOCK)
+
+#define HSDK_PLL_ERR() \
+ !!(ioread32((void __iomem *) CGU_PLL_STATUS) & CGU_PLL_STATUS_ERR)
+
+static void __init hsdk_set_cpu_freq_1ghz(void)
+{
+ u32 timeout = HSDK_PLL_LOCK_TIMEOUT;
+
+ /*
+ * As we set cpu clock which exceeds 500MHz, the divider for the interface
+ * clock must be programmed to div-by-2.
+ */
+ iowrite32(CREG_CORE_IF_CLK_DIV_2, (void __iomem *) CREG_CORE_IF_CLK_DIV);
+
+ /* Set cpu clock to 1GHz */
+ iowrite32(CGU_PLL_CTRL_1GHZ, (void __iomem *) CGU_PLL_CTRL);
+
+ while (!HSDK_PLL_LOCKED() && timeout--)
+ cpu_relax();
+
+ if (!HSDK_PLL_LOCKED() || HSDK_PLL_ERR())
+ pr_err("Failed to setup CPU frequency to 1GHz!");
+}
+
+static void __init hsdk_init_early(void)
+{
+ /*
+ * PAE remapping for DMA clients does not work due to an RTL bug, so
+ * CREG_PAE register must be programmed to all zeroes, otherwise it
+ * will cause problems with DMA to/from peripherals even if PAE40 is
+ * not used.
+ */
+
+ /* Default is 1, which means "PAE offset = 4GByte" */
+ writel_relaxed(0, (void __iomem *) CREG_PAE);
+
+ /* Really apply settings made above */
+ writel(1, (void __iomem *) CREG_PAE_UPDATE);
+
+ /*
+ * Setup CPU frequency to 1GHz.
+ * TODO: remove it after smart hsdk pll driver will be introduced.
+ */
+ hsdk_set_cpu_freq_1ghz();
+}
+
+static const char *hsdk_compat[] __initconst = {
+ "snps,hsdk",
+ NULL,
+};
+
+MACHINE_START(SIMULATION, "hsdk")
+ .dt_compat = hsdk_compat,
+ .init_early = hsdk_init_early,
+ .init_per_cpu = hsdk_init_per_cpu,
+MACHINE_END
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