soc/intel/braswell: Correct serial IRQ support

Serial IRQ was configured in quiet mode, but not enabled.
Enable serial IRQ and use 'enum seriirq_mode' as a devicetree
option.

Function sc_enable_serial_irqs() is added to enabled serial IRQs.
enable_serirq_quiet_mode() is renamed to
sc_set_serial_irqs_mode(). This function use the 'serirq_mode' to
set the mode. The call to this function is moved from finalize to init
having serial IRQs enable in early stage.

Serial IRQs must be enabled in continuous mode for at least one frame
before switching into quiet mode.

BUG=N/A
TEST=Portwell PQ7-M107

Change-Id: I7844cad69dc0563fa6109d779d0afb7c2edd7245
Signed-off-by: Frans Hendriks <fhendriks@eltan.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/29398
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Michał Żygowski <michal.zygowski@3mdeb.com>

3 files changed, 38 insertions, 10 deletions

diff --git a/src/soc/intel/braswell/chip.h b/src/soc/intel/braswell/chip.h
index 9fde4d12a6..4afaf44417 100644
--- a/src/soc/intel/braswell/chip.h
+++ b/src/soc/intel/braswell/chip.h
@@ -3,6 +3,7 @@
  *
  * Copyright (C) 2013 Google Inc.
  * Copyright (C) 2015 Intel Corp.
+ * Copyright (C) 2019 Eltan B.V.
  *
  * 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
@@ -24,6 +25,7 @@
 
 #include <stdint.h>
 #include <fsp/util.h>
+#include <intelblocks/lpc_lib.h>
 #include <soc/pci_devs.h>
 
 #define SVID_CONFIG1		1
@@ -54,6 +56,8 @@ struct soc_intel_braswell_config {
 	uint8_t enable_xdp_tap;
 	uint8_t clkreq_enable;
 
+	enum serirq_mode serirq_mode;
+
 	/* Disable SLP_X stretching after SUS power well loss. */
 	int disable_slp_x_stretch_sus_fail;
 
diff --git a/src/soc/intel/braswell/include/soc/lpc.h b/src/soc/intel/braswell/include/soc/lpc.h
index 7b1e3424e9..1a56f9e8c1 100644
--- a/src/soc/intel/braswell/include/soc/lpc.h
+++ b/src/soc/intel/braswell/include/soc/lpc.h
@@ -31,6 +31,10 @@
 #define UART_CONT	0x80
 #define RCBA		0xf0
 
+/* iLB Memory Mapped IO */
+#define ILB_OIC		0x60
+#define  SIRQEN		(1 << 12)
+
 /* Memory Mapped IO in LPC bridge */
 #define SCNT		0x10
 #define SCNT_MODE	(1 << 7) /* When cleared, SERIRQ is in quiet mode */
diff --git a/src/soc/intel/braswell/southcluster.c b/src/soc/intel/braswell/southcluster.c
index e79cb128a5..000790d9a6 100644
--- a/src/soc/intel/braswell/southcluster.c
+++ b/src/soc/intel/braswell/southcluster.c
@@ -28,6 +28,7 @@
 #include <device/device.h>
 #include <device/pci.h>
 #include <device/pci_ids.h>
+#include <intelblocks/lpc_lib.h>
 #include <pc80/isa-dma.h>
 #include <pc80/i8254.h>
 #include <pc80/i8259.h>
@@ -41,17 +42,23 @@
 #include <soc/spi.h>
 #include <spi-generic.h>
 #include <stdint.h>
-#include <reg_script.h>
 
-static const struct reg_script ops[] = {
-	REG_MMIO_RMW32(ILB_BASE_ADDRESS + SCNT,
-		~SCNT_MODE, 0),	/* put LPC SERIRQ in Quiet Mode */
-	REG_SCRIPT_END
-};
-
-static void enable_serirq_quiet_mode(void)
+static void sc_set_serial_irqs_mode(struct device *dev, enum serirq_mode mode)
 {
-	reg_script_run(ops);
+	u8 *ilb_base = (u8 *)(pci_read_config32(dev, IBASE) & ~0xF);
+
+	switch (mode) {
+	case SERIRQ_CONTINUOUS:
+		break;
+	case SERIRQ_OFF:
+		write32(ilb_base + ILB_OIC, read32(ilb_base + ILB_OIC) &
+			~SIRQEN);
+		break;
+	case SERIRQ_QUIET:
+	default:
+		write8(ilb_base + SCNT, read8(ilb_base + SCNT) & ~SCNT_MODE);
+		break;
+	}
 }
 
 static inline void
@@ -85,6 +92,15 @@ static void sc_add_mmio_resources(struct device *dev)
 #define LPC_DEFAULT_IO_RANGE_LOWER 0
 #define LPC_DEFAULT_IO_RANGE_UPPER 0x1000
 
+static void sc_enable_serial_irqs(struct device *dev)
+{
+	u8 *ilb_base = (u8 *)(pci_read_config32(dev, IBASE) & ~0xF);
+
+	printk(BIOS_SPEW, "Enable serial irq\n");
+	write32(ilb_base + ILB_OIC, read32(ilb_base + ILB_OIC) | SIRQEN);
+	write8(ilb_base + SCNT, read8(ilb_base + SCNT) | SCNT_MODE);
+}
+
 /*
  * Write PCI config space IRQ assignments.  PCI devices have the INT_LINE
  * (0x3C) and INT_PIN (0x3D) registers which report interrupt routing
@@ -285,6 +301,8 @@ static void sc_init(struct device *dev)
 
 	isa_dma_init();
 
+	sc_enable_serial_irqs(dev);
+
 	/* Set up the PIRQ PIC routing based on static config. */
 	for (i = 0; i < NUM_PIRQS; i++)
 		write8((void *)(pr_base + i*sizeof(ir->pic[i])),
@@ -320,6 +338,9 @@ static void sc_init(struct device *dev)
 
 	/* Initialize i8254 timers */
 	setup_i8254();
+
+	sc_set_serial_irqs_mode(dev, config->serirq_mode);
+
 }
 
 /*
@@ -630,7 +651,6 @@ static void finalize_chipset(void *unused)
 		write32(spi + LVSCC, cfg.lvscc | VCL);
 	}
 	spi_init();
-	enable_serirq_quiet_mode();
 
 	printk(BIOS_DEBUG, "Finalizing SMM.\n");
 	outb(APM_CNT_FINALIZE, APM_CNT);