mpc83xx: Add support for MPC83xx PCI-E controllers

This patch adds support for MPC83xx PCI-E controllers in Root Complex
mode.

The patch is based on Tony Li and Dave Liu work[1].

Though unlike the original patch, by default we don't register PCI-E
buses for use in U-Boot, we only configure the controllers for future
use in other OSes (Linux). This is done because we don't have enough
of spare BATs to map all the PCI-E regions.

To actually use PCI-E in U-Boot, users should explicitly define
CONFIG_83XX_GENERIC_PCIE_REGISTER_HOSES symbol in the board file. And
only then U-Boot will able to access PCI-E, but at the cost of disabled
address translation.

[1] http://lists.denx.de/pipermail/u-boot/2008-January/027630.html

Signed-off-by: Tony Li <tony.li@freescale.com>
Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Acked-by: Dave Liu <daveliu@freescale.com>
Signed-off-by: Kim Phillips <kim.phillips@freescale.com>
diff --git a/cpu/mpc83xx/pcie.c b/cpu/mpc83xx/pcie.c
new file mode 100644
index 0000000..02150ba
--- /dev/null
+++ b/cpu/mpc83xx/pcie.c
@@ -0,0 +1,314 @@
+/*
+ * Copyright (C) 2007-2009  Freescale Semiconductor, Inc.
+ * Copyright (C) 2008-2009  MontaVista Software, Inc.
+ *
+ * Authors: Tony Li <tony.li@freescale.com>
+ *          Anton Vorontsov <avorontsov@ru.mvista.com>
+ *
+ * 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; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#include <common.h>
+#include <pci.h>
+#include <mpc83xx.h>
+#include <asm/io.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+#define PCIE_MAX_BUSES 2
+
+#ifdef CONFIG_83XX_GENERIC_PCIE_REGISTER_HOSES
+
+static int mpc83xx_pcie_remap_cfg(struct pci_controller *hose, pci_dev_t dev)
+{
+	int bus = PCI_BUS(dev) - hose->first_busno;
+	immap_t *immr = (immap_t *)CONFIG_SYS_IMMR;
+	pex83xx_t *pex = &immr->pciexp[bus];
+	struct pex_outbound_window *out_win = &pex->bridge.pex_outbound_win[0];
+	u8 devfn = PCI_DEV(dev) << 3 | PCI_FUNC(dev);
+	u32 dev_base = bus << 24 | devfn << 16;
+
+	if (hose->indirect_type == INDIRECT_TYPE_NO_PCIE_LINK)
+		return -1;
+	/*
+	 * Workaround for the HW bug: for Type 0 configure transactions the
+	 * PCI-E controller does not check the device number bits and just
+	 * assumes that the device number bits are 0.
+	 */
+	if (devfn & 0xf8)
+		return -1;
+
+	out_le32(&out_win->tarl, dev_base);
+	return 0;
+}
+
+#define cfg_read(val, addr, type, op) \
+	do { *val = op((type)(addr)); } while (0)
+#define cfg_write(val, addr, type, op) \
+	do { op((type *)(addr), (val)); } while (0)
+
+#define PCIE_OP(rw, size, type, op)					\
+static int pcie_##rw##_config_##size(struct pci_controller *hose,	\
+				     pci_dev_t dev, int offset,		\
+				     type val)				\
+{									\
+	int ret;							\
+									\
+	ret = mpc83xx_pcie_remap_cfg(hose, dev);			\
+	if (ret)							\
+		return ret;						\
+	cfg_##rw(val, (void *)hose->cfg_addr + offset, type, op);	\
+	return 0;							\
+}
+
+PCIE_OP(read, byte, u8 *, in_8)
+PCIE_OP(read, word, u16 *, in_le16)
+PCIE_OP(read, dword, u32 *, in_le32)
+PCIE_OP(write, byte, u8, out_8)
+PCIE_OP(write, word, u16, out_le16)
+PCIE_OP(write, dword, u32, out_le32)
+
+static void mpc83xx_pcie_register_hose(int bus, struct pci_region *reg,
+				       u8 link)
+{
+	extern void disable_addr_trans(void); /* start.S */
+	static struct pci_controller pcie_hose[PCIE_MAX_BUSES];
+	static int max_bus;
+	struct pci_controller *hose = &pcie_hose[bus];
+	int i;
+
+	/*
+	 * There are no spare BATs to remap all PCI-E windows for U-Boot, so
+	 * disable translations. In general, this is not great solution, and
+	 * that's why we don't register PCI-E hoses by default.
+	 */
+	disable_addr_trans();
+
+	for (i = 0; i < 2; i++, reg++) {
+		if (reg->size == 0)
+			break;
+
+		hose->regions[i] = *reg;
+		hose->region_count++;
+	}
+
+	i = hose->region_count++;
+	hose->regions[i].bus_start = 0;
+	hose->regions[i].phys_start = 0;
+	hose->regions[i].size = gd->ram_size;
+	hose->regions[i].flags = PCI_REGION_MEM | PCI_REGION_MEMORY;
+
+	i = hose->region_count++;
+	hose->regions[i].bus_start = CONFIG_SYS_IMMR;
+	hose->regions[i].phys_start = CONFIG_SYS_IMMR;
+	hose->regions[i].size = 0x100000;
+	hose->regions[i].flags = PCI_REGION_MEM | PCI_REGION_MEMORY;
+
+	hose->first_busno = max_bus;
+	hose->last_busno = 0xff;
+
+	if (bus == 0)
+		hose->cfg_addr = (unsigned int *)CONFIG_SYS_PCIE1_CFG_BASE;
+	else
+		hose->cfg_addr = (unsigned int *)CONFIG_SYS_PCIE2_CFG_BASE;
+
+	pci_set_ops(hose,
+			pcie_read_config_byte,
+			pcie_read_config_word,
+			pcie_read_config_dword,
+			pcie_write_config_byte,
+			pcie_write_config_word,
+			pcie_write_config_dword);
+
+	if (!link)
+		hose->indirect_type = INDIRECT_TYPE_NO_PCIE_LINK;
+
+	pci_register_hose(hose);
+
+#ifdef CONFIG_PCI_SCAN_SHOW
+	printf("PCI:   Bus Dev VenId DevId Class Int\n");
+#endif
+	/*
+	 * Hose scan.
+	 */
+	hose->last_busno = pci_hose_scan(hose);
+	max_bus = hose->last_busno + 1;
+}
+
+#else
+
+static void mpc83xx_pcie_register_hose(int bus, struct pci_region *reg,
+				       u8 link) {}
+
+#endif /* CONFIG_83XX_GENERIC_PCIE_REGISTER_HOSES */
+
+static void mpc83xx_pcie_init_bus(int bus, struct pci_region *reg)
+{
+	immap_t *immr = (immap_t *)CONFIG_SYS_IMMR;
+	pex83xx_t *pex = &immr->pciexp[bus];
+	struct pex_outbound_window *out_win;
+	struct pex_inbound_window *in_win;
+	void *hose_cfg_base;
+	unsigned int ram_sz;
+	unsigned int barl;
+	unsigned int tar;
+	u16 reg16;
+	int i;
+
+	/* Enable pex csb bridge inbound & outbound transactions */
+	out_le32(&pex->bridge.pex_csb_ctrl,
+		in_le32(&pex->bridge.pex_csb_ctrl) | PEX_CSB_CTRL_OBPIOE |
+		PEX_CSB_CTRL_IBPIOE);
+
+	/* Enable bridge outbound */
+	out_le32(&pex->bridge.pex_csb_obctrl, PEX_CSB_OBCTRL_PIOE |
+		PEX_CSB_OBCTRL_MEMWE | PEX_CSB_OBCTRL_IOWE |
+		PEX_CSB_OBCTRL_CFGWE);
+
+	out_win = &pex->bridge.pex_outbound_win[0];
+	if (bus) {
+		out_le32(&out_win->ar, PEX_OWAR_EN | PEX_OWAR_TYPE_CFG |
+			CONFIG_SYS_PCIE2_CFG_SIZE);
+		out_le32(&out_win->bar, CONFIG_SYS_PCIE2_CFG_BASE);
+	} else {
+		out_le32(&out_win->ar, PEX_OWAR_EN | PEX_OWAR_TYPE_CFG |
+			CONFIG_SYS_PCIE1_CFG_SIZE);
+		out_le32(&out_win->bar, CONFIG_SYS_PCIE1_CFG_BASE);
+	}
+	out_le32(&out_win->tarl, 0);
+	out_le32(&out_win->tarh, 0);
+
+	for (i = 0; i < 2; i++, reg++) {
+		u32 ar;
+
+		if (reg->size == 0)
+			break;
+
+		out_win = &pex->bridge.pex_outbound_win[i + 1];
+		out_le32(&out_win->bar, reg->phys_start);
+		out_le32(&out_win->tarl, reg->bus_start);
+		out_le32(&out_win->tarh, 0);
+		ar = PEX_OWAR_EN | (reg->size & PEX_OWAR_SIZE);
+		if (reg->flags & PCI_REGION_IO)
+			ar |= PEX_OWAR_TYPE_IO;
+		else
+			ar |= PEX_OWAR_TYPE_MEM;
+		out_le32(&out_win->ar, ar);
+	}
+
+	out_le32(&pex->bridge.pex_csb_ibctrl, PEX_CSB_IBCTRL_PIOE);
+
+	ram_sz = gd->ram_size;
+	barl = 0;
+	tar = 0;
+	i = 0;
+	while (ram_sz > 0) {
+		in_win = &pex->bridge.pex_inbound_win[i];
+		out_le32(&in_win->barl, barl);
+		out_le32(&in_win->barh, 0x0);
+		out_le32(&in_win->tar, tar);
+		if (ram_sz >= 0x10000000) {
+			/* The maxium windows size is 256M */
+			out_le32(&in_win->ar, PEX_IWAR_EN | PEX_IWAR_NSOV |
+				PEX_IWAR_TYPE_PF | 0x0FFFF000);
+			barl += 0x10000000;
+			tar += 0x10000000;
+			ram_sz -= 0x10000000;
+		} else {
+			/* The UM  is not clear here.
+			 * So, round up to even Mb boundary */
+
+			ram_sz = ram_sz >> (20 +
+					((ram_sz & 0xFFFFF) ? 1 : 0));
+			if (!(ram_sz % 2))
+				ram_sz -= 1;
+			out_le32(&in_win->ar, PEX_IWAR_EN | PEX_IWAR_NSOV |
+				PEX_IWAR_TYPE_PF | (ram_sz << 20) | 0xFF000);
+			ram_sz = 0;
+		}
+		i++;
+	}
+
+	in_win = &pex->bridge.pex_inbound_win[i];
+	out_le32(&in_win->barl, CONFIG_SYS_IMMR);
+	out_le32(&in_win->barh, 0);
+	out_le32(&in_win->tar, CONFIG_SYS_IMMR);
+	out_le32(&in_win->ar, PEX_IWAR_EN |
+		PEX_IWAR_TYPE_NO_PF | PEX_IWAR_SIZE_1M);
+
+	/* Enable the host virtual INTX interrupts */
+	out_le32(&pex->bridge.pex_int_axi_misc_enb,
+		in_le32(&pex->bridge.pex_int_axi_misc_enb) | 0x1E0);
+
+	/* Hose configure header is memory-mapped */
+	hose_cfg_base = (void *)pex;
+
+	get_clocks();
+	/* Configure the PCIE controller core clock ratio */
+	out_le32(hose_cfg_base + PEX_GCLK_RATIO,
+		(((bus ? gd->pciexp2_clk : gd->pciexp1_clk) / 1000000) * 16)
+		/ 333);
+	udelay(1000000);
+
+	/* Do Type 1 bridge configuration */
+	out_8(hose_cfg_base + PCI_PRIMARY_BUS, 0);
+	out_8(hose_cfg_base + PCI_SECONDARY_BUS, 1);
+	out_8(hose_cfg_base + PCI_SUBORDINATE_BUS, 255);
+
+	/*
+	 * Write to Command register
+	 */
+	reg16 = in_le16(hose_cfg_base + PCI_COMMAND);
+	reg16 |= PCI_COMMAND_MASTER | PCI_COMMAND_MEMORY | PCI_COMMAND_IO |
+			PCI_COMMAND_SERR | PCI_COMMAND_PARITY;
+	out_le16(hose_cfg_base + PCI_COMMAND, reg16);
+
+	/*
+	 * Clear non-reserved bits in status register.
+	 */
+	out_le16(hose_cfg_base + PCI_STATUS, 0xffff);
+	out_8(hose_cfg_base + PCI_LATENCY_TIMER, 0x80);
+	out_8(hose_cfg_base + PCI_CACHE_LINE_SIZE, 0x08);
+
+	printf("PCIE%d: ", bus);
+
+	reg16 = in_le16(hose_cfg_base + PCI_LTSSM);
+	if (reg16 >= PCI_LTSSM_L0)
+		printf("link\n");
+	else
+		printf("No link\n");
+
+	mpc83xx_pcie_register_hose(bus, reg, reg16 >= PCI_LTSSM_L0);
+}
+
+/*
+ * The caller must have already set SCCR, SERDES and the PCIE_LAW BARs
+ * must have been set to cover all of the requested regions.
+ */
+void mpc83xx_pcie_init(int num_buses, struct pci_region **reg, int warmboot)
+{
+	int i;
+
+	/*
+	 * Release PCI RST Output signal.
+	 * Power on to RST high must be at least 100 ms as per PCI spec.
+	 * On warm boots only 1 ms is required.
+	 */
+	udelay(warmboot ? 1000 : 100000);
+
+	for (i = 0; i < num_buses; i++)
+		mpc83xx_pcie_init_bus(i, reg[i]);
+}