soc/intel/common/block: Add Intel common ITSS code support

Create Intel Common ITSS code. This code currently only contains
the code for Interrupt initialization required in Bootblock phase.
More code will get added up in the subsequent phases.

Change-Id: I133294188eb5d1312caeafcb621fb650a7fab371
Signed-off-by: Barnali Sarkar <barnali.sarkar@intel.com>
Signed-off-by: Bora Guvendik <bora.guvendik@intel.com>
Reviewed-on: https://review.coreboot.org/19125
Tested-by: build bot (Jenkins)
Reviewed-by: Aaron Durbin <adurbin@chromium.org>

3 files changed, 147 insertions, 0 deletions

diff --git a/src/soc/intel/common/block/itss/Kconfig b/src/soc/intel/common/block/itss/Kconfig
new file mode 100644
index 0000000000..2f1a1004ad
--- /dev/null
+++ b/src/soc/intel/common/block/itss/Kconfig
@@ -0,0 +1,4 @@
+config SOC_INTEL_COMMON_BLOCK_ITSS
+	bool
+	help
+	  Intel Processor common interrupt timer subsystem support
diff --git a/src/soc/intel/common/block/itss/Makefile.inc b/src/soc/intel/common/block/itss/Makefile.inc
new file mode 100644
index 0000000000..bc0e97a2f9
--- /dev/null
+++ b/src/soc/intel/common/block/itss/Makefile.inc
@@ -0,0 +1,3 @@
+bootblock-$(CONFIG_SOC_INTEL_COMMON_BLOCK_ITSS) += itss.c
+romstage-$(CONFIG_SOC_INTEL_COMMON_BLOCK_ITSS) += itss.c
+ramstage-$(CONFIG_SOC_INTEL_COMMON_BLOCK_ITSS) += itss.c
diff --git a/src/soc/intel/common/block/itss/itss.c b/src/soc/intel/common/block/itss/itss.c
new file mode 100644
index 0000000000..a217675405
--- /dev/null
+++ b/src/soc/intel/common/block/itss/itss.c
@@ -0,0 +1,140 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2017 Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <stdint.h>
+#include <commonlib/helpers.h>
+#include <console/console.h>
+#include <intelblocks/itss.h>
+#include <intelblocks/pcr.h>
+#include <soc/itss.h>
+#include <soc/pcr_ids.h>
+
+void itss_irq_init(uint8_t pch_interrupt_routing[MAX_PXRC_CONFIG])
+{
+	uint8_t index = 0;
+
+	for (index = 0; index < MAX_PXRC_CONFIG; index++) {
+		uint8_t val = pch_interrupt_routing[index];
+		uint8_t irq = val & 0xf;
+
+		if (irq == 8 || irq == 13)
+			continue;
+		if (irq <= 2)
+			continue;
+
+		pcr_write8(PID_ITSS, PCR_ITSS_PIRQA_ROUT + index, val);
+	}
+}
+
+void itss_clock_gate_8254(void)
+{
+	const uint32_t cge8254_mask = (1 << 2);
+
+	pcr_rmw32(PID_ITSS, PCR_ITSS_ITSSPRC, ~cge8254_mask, cge8254_mask);
+}
+
+void itss_set_irq_polarity(int irq, int active_low)
+{
+	uint32_t mask;
+	uint16_t reg;
+	const uint16_t port = PID_ITSS;
+
+	if (irq < 0 || irq > ITSS_MAX_IRQ)
+		return;
+
+	reg = PCR_ITSS_IPC0_CONF + sizeof(uint32_t) * (irq / IRQS_PER_IPC);
+	mask = 1 << (irq % IRQS_PER_IPC);
+
+	pcr_rmw32(port, reg, ~mask, (active_low ? mask : 0));
+}
+
+static uint32_t irq_snapshot[NUM_IPC_REGS];
+
+void itss_snapshot_irq_polarities(int start, int end)
+{
+	int i;
+	int reg_start;
+	int reg_end;
+	const uint16_t port = PID_ITSS;
+
+	if (start < 0 || start > ITSS_MAX_IRQ ||
+	    end < 0 || end > ITSS_MAX_IRQ || end < start)
+		return;
+
+	reg_start = start / IRQS_PER_IPC;
+	reg_end = (end + IRQS_PER_IPC - 1) / IRQS_PER_IPC;
+
+	for (i = reg_start; i < reg_end; i++) {
+		uint16_t reg = PCR_ITSS_IPC0_CONF + sizeof(uint32_t) * i;
+		irq_snapshot[i] = pcr_read32(port, reg);
+	}
+}
+
+static void show_irq_polarities(const char *msg)
+{
+	int i;
+	const uint16_t port = PID_ITSS;
+
+	printk(BIOS_INFO, "ITSS IRQ Polarities %s:\n", msg);
+	for (i = 0; i < NUM_IPC_REGS; i++) {
+		uint16_t reg = PCR_ITSS_IPC0_CONF + sizeof(uint32_t) * i;
+		printk(BIOS_INFO, "IPC%d: 0x%08x\n", i, pcr_read32(port, reg));
+	}
+}
+
+void itss_restore_irq_polarities(int start, int end)
+{
+	int i;
+	int reg_start;
+	int reg_end;
+	const uint16_t port = PID_ITSS;
+
+	if (start < 0 || start > ITSS_MAX_IRQ ||
+	    end < 0 || end > ITSS_MAX_IRQ || end < start)
+		return;
+
+	show_irq_polarities("Before");
+
+	reg_start = start / IRQS_PER_IPC;
+	reg_end = (end + IRQS_PER_IPC - 1) / IRQS_PER_IPC;
+
+	for (i = reg_start; i < reg_end; i++) {
+		uint32_t mask;
+		uint16_t reg;
+		int irq_start;
+		int irq_end;
+
+		irq_start = i * IRQS_PER_IPC;
+		irq_end = MIN(irq_start + IRQS_PER_IPC - 1, ITSS_MAX_IRQ);
+
+		if (start > irq_end)
+			continue;
+		if (end < irq_start)
+			break;
+
+		/* Track bits within the bounds of of the register. */
+		irq_start = MAX(start, irq_start) % IRQS_PER_IPC;
+		irq_end = MIN(end, irq_end) % IRQS_PER_IPC;
+
+		/* Create bitmask of the inclusive range of start and end. */
+		mask = (((1U << irq_end) - 1) | (1U << irq_end));
+		mask &= ~((1U << irq_start) - 1);
+
+		reg = PCR_ITSS_IPC0_CONF + sizeof(uint32_t) * i;
+		pcr_rmw32(port, reg, ~mask, (mask & irq_snapshot[i]));
+	}
+
+	show_irq_polarities("After");
+}