[Skiboot] [PATCH 28/61] platforms: Add Rainier

[Vasant Hegde]

From: Alistair Popple <alistair at popple.id.au>

Rainier comes in two variants; 4U and 2U.

PCIe slot power on from oohall with multi-socket support from fbarrat:

On Rainier the PCIe slots have individual slot power controllers. These
need to be enabled at boot so that we can scan the devices in the PHB
root ports.

This should really be integrated into the OPAL slot power control
framework that was used for PCIe Hotplug support on Frienze (P8 FSP
systems). Unfortunately, the way that is implemented is difficult to
extend at best and needs to be refactored before we can add support
for runtime power control on rainier.

Signed-off-by: Alistair Popple <alistair at popple.id.au>
Signed-off-by: Oliver O'Halloran <oohall at gmail.com>
Signed-off-by: Frederic Barrat <fbarrat at linux.ibm.com>
[arbab at linux.ibm.com: Use bmc_plat_ast2600_openbmc]
Signed-off-by: Reza Arbab <arbab at linux.ibm.com>
Signed-off-by: Vasant Hegde <hegdevasant at linux.vnet.ibm.com>
---
 platforms/astbmc/Makefile.inc |   3 +-
 platforms/astbmc/rainier.c    | 136 ++++++++++++++++++++++++++++++++++
 2 files changed, 137 insertions(+), 2 deletions(-)
 create mode 100644 platforms/astbmc/rainier.c

diff --git a/platforms/astbmc/Makefile.inc b/platforms/astbmc/Makefile.inc
index 24e94039f..070813231 100644
--- a/platforms/astbmc/Makefile.inc
+++ b/platforms/astbmc/Makefile.inc
@@ -7,8 +7,7 @@ ASTBMC_OBJS = pnor.o common.o slots.o \
 	      witherspoon.o zaius.o romulus.o p9dsu.o \
 	      vesnin.o nicole.o mihawk.o mowgli.o \
 	      talos.o blackbird.o \
-	      swift.o
+	      swift.o rainier.o
 
 ASTBMC = $(PLATDIR)/astbmc/built-in.a
 $(ASTBMC): $(ASTBMC_OBJS:%=$(PLATDIR)/astbmc/%)
-
diff --git a/platforms/astbmc/rainier.c b/platforms/astbmc/rainier.c
new file mode 100644
index 000000000..17d9fe2bf
--- /dev/null
+++ b/platforms/astbmc/rainier.c
@@ -0,0 +1,136 @@
+// SPDX-License-Identifier: Apache-2.0
+/*
+ * Copyright (c) 2020 IBM
+ */
+
+#include <skiboot.h>
+#include <device.h>
+#include <ipmi.h>
+#include <chip.h>
+#include <i2c.h>
+#include <timebase.h>
+
+#include "astbmc.h"
+
+/*
+ * puti2c pu 2 1 C6 00 6 1 -quiet
+ * puti2c pu 2 1 C6 54 7 1 -quiet
+ * puti2c pu 2 1 C6 05 8 1 -quiet
+ * puti2c pu 2 1 C6 00 9 1 -quiet
+ *
+ * sleep 4
+ *
+ * puti2c pu 2 1 C6 55 6 1 -quiet
+ * puti2c pu 2 1 C6 55 7 1 -quiet
+ * 	2  - engine
+ * 	1  - port
+ * 	C6 - slave addr
+ * 	55 - data
+ * 	7  - register
+ * 	1  - register length?
+ */
+
+static int64_t smbus_write8(struct i2c_bus *bus, uint8_t reg, uint8_t data)
+{
+	struct i2c_request req;
+
+	memset(&req, 0, sizeof(req));
+
+	req.bus	= bus;
+	req.dev_addr   = 0xC6 >> 1; /* Docs use 8bit addresses */
+
+	req.op         = SMBUS_WRITE;
+	req.offset     = reg;
+	req.offset_bytes = 1;
+	req.rw_buf     = &data;
+	req.rw_len     = 1;
+	req.timeout = 100;
+
+	return i2c_request_sync(&req);
+}
+
+static int64_t slot_power_enable(struct i2c_bus *bus)
+{
+	/* FIXME: we could do this in one transaction using auto-increment */
+	if (smbus_write8(bus, 0x6, 0x00))
+		return -1;
+	if (smbus_write8(bus, 0x7, 0x54))
+		return -1;
+	if (smbus_write8(bus, 0x8, 0x05))
+		return -1;
+	if (smbus_write8(bus, 0x9, 0x00))
+		return -1;
+
+	/* FIXME: Poll for PGOOD going high */
+
+	if (smbus_write8(bus, 0x6, 0x55))
+		return -1;
+	if (smbus_write8(bus, 0x7, 0x55))
+		return -1;
+
+	return 0;
+}
+
+static void rainier_init_slot_power(void)
+{
+	struct proc_chip *chip;
+	struct i2c_bus *bus;
+
+	/*
+	 * Controller on P0 is for slots C7 -> C11
+	 *            on P2 is for slots C0 -> C4
+	 * Both chips use engine 2 port 1
+	 *
+	 * Rainier with only one socket is officially supported, so
+	 * we may not have slots C0 -> C4
+	 */
+	for_each_chip(chip) {
+		if (chip->id % 4)
+			continue;
+		bus = p8_i2c_add_bus(chip->id, 2, 1, 400000);
+		if (!bus) {
+			prerror("Unable to find PCIe power controller I2C bus!\n");
+			return;
+		}
+		if (slot_power_enable(bus)) {
+			prerror("Error enabling PCIe slot power on chip %d\n",
+				chip->id);
+		}
+	}
+}
+
+static void rainier_init(void)
+{
+	astbmc_init();
+	rainier_init_slot_power();
+}
+
+static bool rainier_probe(void)
+{
+	if (!dt_node_is_compatible(dt_root, "ibm,rainier") &&
+	    !dt_node_is_compatible(dt_root, "ibm,rainier-2s2u") &&
+	    !dt_node_is_compatible(dt_root, "ibm,rainier-2s4u"))
+		return false;
+
+	/* Lot of common early inits here */
+	astbmc_early_init();
+
+	/* Setup UART for use by OPAL (Linux hvc) */
+	uart_set_console_policy(UART_CONSOLE_OPAL);
+
+	return true;
+}
+
+DECLARE_PLATFORM(rainier) = {
+	.name			= "Rainier",
+	.probe			= rainier_probe,
+	.init			= rainier_init,
+	.start_preload_resource	= flash_start_preload_resource,
+	.resource_loaded	= flash_resource_loaded,
+	.bmc			= &bmc_plat_ast2600_openbmc,
+	.cec_power_down         = astbmc_ipmi_power_down,
+	.cec_reboot             = astbmc_ipmi_reboot,
+	.elog_commit		= ipmi_elog_commit,
+	.exit			= astbmc_exit,
+	.terminate		= ipmi_terminate,
+};
-- 
2.31.1