/*
* Coherency fabric (Aurora) support for Armada 370 and XP platforms.
*
* Copyright (C) 2012 Marvell
*
* Yehuda Yitschak <yehuday@marvell.com>
* Gregory Clement <gregory.clement@free-electrons.com>
* Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
*
* This file is licensed under the terms of the GNU General Public
* License version 2. This program is licensed "as is" without any
* warranty of any kind, whether express or implied.
*
* The Armada 370 and Armada XP SOCs have a coherency fabric which is
* responsible for ensuring hardware coherency between all CPUs and between
* CPUs and I/O masters. This file initializes the coherency fabric and
* supplies basic routines for configuring and controlling hardware coherency
*/
#define pr_fmt(fmt) "mvebu-coherency: " fmt
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/of_address.h>
#include <linux/io.h>
#include <linux/smp.h>
#include <linux/dma-mapping.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/mbus.h>
#include <linux/clk.h>
#include <linux/pci.h>
#include <asm/smp_plat.h>
#include <asm/cacheflush.h>
#include <asm/mach/map.h>
#include "armada-370-xp.h"
#include "coherency.h"
#include "mvebu-soc-id.h"
unsigned long coherency_phys_base;
void __iomem *coherency_base;
static void __iomem *coherency_cpu_base;
/* Coherency fabric registers */
#define COHERENCY_FABRIC_CFG_OFFSET 0x4
#define IO_SYNC_BARRIER_CTL_OFFSET 0x0
enum {
COHERENCY_FABRIC_TYPE_NONE,
COHERENCY_FABRIC_TYPE_ARMADA_370_XP,
COHERENCY_FABRIC_TYPE_ARMADA_375,
COHERENCY_FABRIC_TYPE_ARMADA_380,
};
static struct of_device_id of_coherency_table[] = {
{.compatible = "marvell,coherency-fabric",
.data = (void *) COHERENCY_FABRIC_TYPE_ARMADA_370_XP },
{.compatible = "marvell,armada-375-coherency-fabric",
.data = (void *) COHERENCY_FABRIC_TYPE_ARMADA_375 },
{.compatible = "marvell,armada-380-coherency-fabric",
.data = (void *) COHERENCY_FABRIC_TYPE_ARMADA_380 },
{ /* end of list */ },
};
/* Functions defined in coherency_ll.S */
int ll_enable_coherency(void);
void ll_add_cpu_to_smp_group(void);
int set_cpu_coherent(void)
{
if (!coherency_base) {
pr_warn("Can't make current CPU cache coherent.\n");
pr_warn("Coherency fabric is not initialized\n");
return 1;
}
ll_add_cpu_to_smp_group();
return ll_enable_coherency();
}
/*
* The below code implements the I/O coherency workaround on Armada
* 375. This workaround consists in using the two channels of the
* first XOR engine to trigger a XOR transaction that serves as the
* I/O coherency barrier.
*/
static void __iomem *xor_base, *xor_high_base;
static dma_addr_t coherency_wa_buf_phys[CONFIG_NR_CPUS];
static void *coherency_wa_buf[CONFIG_NR_CPUS];
static bool coherency_wa_enabled;
#define XOR_CONFIG(chan) (0x10 + (chan * 4))
#define XOR_ACTIVATION(chan) (0x20 + (chan * 4))
#define WINDOW_BAR_ENABLE(chan) (0x240 + ((chan) << 2))
#define WINDOW_BASE(w) (0x250 + ((w) << 2))
#define WINDOW_SIZE(w) (0x270 + ((w) << 2))
#define WINDOW_REMAP_HIGH(w) (0x290 + ((w) << 2))
#define WINDOW_OVERRIDE_CTRL(chan) (0x2A0 + ((chan) << 2))
#define XOR_DEST_POINTER(chan) (0x2B0 + (chan * 4))
#define XOR_BLOCK_SIZE(chan) (0x2C0 + (chan * 4))
#define XOR_INIT_VALUE_LOW 0x2E0
#define XOR_INIT_VALUE_HIGH 0x2E4
static inline void mvebu_hwcc_armada375_sync_io_barrier_wa(void)
{
int idx = smp_processor_id();
/* Write '1' to the first word of the buffer */
writel(0x1, coherency_wa_buf[idx]);
/* Wait until the engine is idle */
while ((readl(xor_base + XOR_ACTIVATION(idx)) >> 4) & 0x3)
;
dmb();
/* Trigger channel */
writel(0x1, xor_base + XOR_ACTIVATION(idx));
/* Poll the data until it is cleared by the XOR transaction */
while (readl(coherency_wa_buf[idx]))
;
}
static void __init armada_375_coherency_init_wa(void)
{
const struct mbus_dram_target_info *dram;
struct device_node *xor_node;
struct property *xor_status;
struct clk *xor_clk;
u32 win_enable = 0;
int i;
pr_warn("enabling coherency workaround for Armada 375 Z1, one XOR engine disabled\n");
/*
* Since the workaround uses one XOR engine, we grab a
* reference to its Device Tree node first.
*/
xor_node = of_find_compatible_node(NULL, NULL, "marvell,orion-xor");
BUG_ON(!xor_node);
/*
* Then we mark it as disabled so that the real XOR driver
* will not use it.
*/
xor_status = kzalloc(sizeof(struct property), GFP_KERNEL);
BUG_ON(!xor_status);
xor_status->value = kstrdup("disabled", GFP_KERNEL);
BUG_ON(!xor_status->value);
xor_status->length = 8;
xor_status->name = kstrdup("status", GFP_KERNEL);
BUG_ON(!xor_status->name);
of_update_property(xor_node, xor_status);
/*
* And we remap the registers, get the clock, and do the
* initial configuration of the XOR engine.
*/
xor_base = of_iomap(xor_node, 0);
xor_high_base = of_iomap(xor_node, 1);
xor_clk = of_clk_get_by_name(xor_node, NULL);
BUG_ON(!xor_clk);
clk_prepare_enable(xor_clk);
dram = mv_mbus_dram_info();
for (i = 0; i < 8; i++) {
writel(0, xor_base + WINDOW_BASE(i));
writel(0, xor_base + WINDOW_SIZE(i));
if (i < 4)
writel(0, xor_base + WINDOW_REMAP_HIGH(i));
}
for (i = 0; i < dram->num_cs; i++) {
const struct mbus_dram_window *cs = dram->cs + i;
writel((cs->base & 0xffff0000) |
(cs->mbus_attr << 8) |
dram->mbus_dram_target_id, xor_base + WINDOW_BASE(i));
writel((cs->size - 1) & 0xffff0000, xor_base + WINDOW_SIZE(i));
win_enable |= (1 << i);
win_enable |= 3 << (16 + (2 * i));
}
writel(win_enable, xor_base + WINDOW_BAR_ENABLE(0));
writel(win_enable, xor_base + WINDOW_BAR_ENABLE(1));
writel(0, xor_base + WINDOW_OVERRIDE_CTRL(0));
writel(0, xor_base + WINDOW_OVERRIDE_CTRL(1));
for (i = 0; i < CONFIG_NR_CPUS; i++) {
coherency_wa_buf[i] = kzalloc(PAGE_SIZE, GFP_KERNEL);
BUG_ON(!coherency_wa_buf[i]);
/*
* We can't use the DMA mapping API, since we don't
* have a valid 'struct device' pointer
*/
coherency_wa_buf_phys[i] =
virt_to_phys(coherency_wa_buf[i]);
BUG_ON(!coherency_wa_buf_phys[i]);
/*
* Configure the XOR engine for memset operation, with
* a 128 bytes block size
*/
writel(0x444, xor_base + XOR_CONFIG(i));
writel(128, xor_base + XOR_BLOCK_SIZE(i));
writel(coherency_wa_buf_phys[i],
xor_base + XOR_DEST_POINTER(i));
}
writel(0x0, xor_base + XOR_INIT_VALUE_LOW);
writel(0x0, xor_base + XOR_INIT_VALUE_HIGH);
coherency_wa_enabled = true;
}
static inline void mvebu_hwcc_sync_io_barrier(void)
{
if (coherency_wa_enabled) {
mvebu_hwcc_armada375_sync_io_barrier_wa();
return;
}
writel(0x1, coherency_cpu_base + IO_SYNC_BARRIER_CTL_OFFSET);
while (readl(coherency_cpu_base + IO_SYNC_BARRIER_CTL_OFFSET) & 0x1);
}
static dma_addr_t mvebu_hwcc_dma_map_page(struct device *dev, struct page *page,
unsigned long offset, size_t size,
enum dma_data_direction dir,
struct dma_attrs *attrs)
{
if (dir != DMA_TO_DEVICE)
mvebu_hwcc_sync_io_barrier();
return pfn_to_dma(dev, page_to_pfn(page)) + offset;
}
static void mvebu_hwcc_dma_unmap_page(struct device *dev, dma_addr_t dma_handle,
size_t size, enum dma_data_direction dir,
struct dma_attrs *attrs)
{
if (dir != DMA_TO_DEVICE)
mvebu_hwcc_sync_io_barrier();
}
static void mvebu_hwcc_dma_sync(struct device *dev, dma_addr_t dma_handle,
size_t size, enum dma_data_direction dir)
{
if (dir != DMA_TO_DEVICE)
mvebu_hwcc_sync_io_barrier();
}
static struct dma_map_ops mvebu_hwcc_dma_ops = {
.alloc = arm_dma_alloc,
.free = arm_dma_free,
.mmap = arm_dma_mmap,
.map_page = mvebu_hwcc_dma_map_page,
.unmap_page = mvebu_hwcc_dma_unmap_page,
.get_sgtable = arm_dma_get_sgtable,
.map_sg = arm_dma_map_sg,
.unmap_sg = arm_dma_unmap_sg,
.sync_single_for_cpu = mvebu_hwcc_dma_sync,
.sync_single_for_device = mvebu_hwcc_dma_sync,
.sync_sg_for_cpu = arm_dma_sync_sg_for_cpu,
.sync_sg_for_device = arm_dma_sync_sg_for_device,
.set_dma_mask = arm_dma_set_mask,
};
static int mvebu_hwcc_notifier(struct notifier_block *nb,
unsigned long event, void *__dev)
{
struct device *dev = __dev;
if (event != BUS_NOTIFY_ADD_DEVICE)
return NOTIFY_DONE;
set_dma_ops(dev, &mvebu_hwcc_dma_ops);
return NOTIFY_OK;
}
static struct notifier_block mvebu_hwcc_nb = {
.notifier_call = mvebu_hwcc_notifier,
};
static void __init armada_370_coherency_init(struct device_node *np)
{
struct resource res;
of_address_to_resource(np, 0, &res);
coherency_phys_base = res.start;
/*
* Ensure secondary CPUs will see the updated value,
* which they read before they join the coherency
* fabric, and therefore before they are coherent with
* the boot CPU cache.
*/
sync_cache_w(&coherency_phys_base);
coherency_base = of_iomap(np, 0);
coherency_cpu_base = of_iomap(np, 1);
set_cpu_coherent();
}
/*
* This ioremap hook is used on Armada 375/38x to ensure that PCIe
* memory areas are mapped as MT_UNCACHED instead of MT_DEVICE. This
* is needed as a workaround for a deadlock issue between the PCIe
* interface and the cache controller.
*/
static void __iomem *
armada_pcie_wa_ioremap_caller(phys_addr_t phys_addr, size_t size,
unsigned int mtype, void *caller)
{
struct resource pcie_mem;
mvebu_mbus_get_pcie_mem_aperture(&pcie_mem);
if (pcie_mem.start <= phys_addr && (phys_addr + size) <= pcie_mem.end)
mtype = MT_UNCACHED;
return __arm_ioremap_caller(phys_addr, size, mtype, caller);
}
static void __init armada_375_380_coherency_init(struct device_node *np)
{
struct device_node *cache_dn;
coherency_cpu_base = of_iomap(np, 0);
arch_ioremap_caller = armada_pcie_wa_ioremap_caller;
/*
* Add the PL310 property "arm,io-coherent". This makes sure the
* outer sync operation is not used, which allows to
* workaround the system erratum that causes deadlocks when
* doing PCIe in an SMP situation on Armada 375 and Armada
* 38x.
*/
for_each_compatible_node(cache_dn, NULL, "arm,pl310-cache") {
struct property *p;
p = kzalloc(sizeof(*p), GFP_KERNEL);
p->name = kstrdup("arm,io-coherent", GFP_KERNEL);
of_add_property(cache_dn, p);
}
}
static int coherency_type(void)
{
struct device_node *np;
const struct of_device_id *match;
np = of_find_matching_node_and_match(NULL, of_coherency_table, &match);
if (np) {
int type = (int) match->data;
/* Armada 370/XP coherency works in both UP and SMP */
if (type == COHERENCY_FABRIC_TYPE_ARMADA_370_XP)
return type;
/* Armada 375 coherency works only on SMP */
else if (type == COHERENCY_FABRIC_TYPE_ARMADA_375 && is_smp())
return type;
/* Armada 380 coherency works only on SMP */
else if (type == COHERENCY_FABRIC_TYPE_ARMADA_380 && is_smp())
return type;
}
return COHERENCY_FABRIC_TYPE_NONE;
}
int coherency_available(void)
{
return coherency_type() != COHERENCY_FABRIC_TYPE_NONE;
}
int __init coherency_init(void)
{
int type = coherency_type();
struct device_node *np;
np = of_find_matching_node(NULL, of_coherency_table);
if (type == COHERENCY_FABRIC_TYPE_ARMADA_370_XP)
armada_370_coherency_init(np);
else if (type == COHERENCY_FABRIC_TYPE_ARMADA_375 ||
type == COHERENCY_FABRIC_TYPE_ARMADA_380)
armada_375_380_coherency_init(np);
return 0;
}
static int __init coherency_late_init(void)
{
int type = coherency_type();
if (type == COHERENCY_FABRIC_TYPE_NONE)
return 0;
if (type == COHERENCY_FABRIC_TYPE_ARMADA_375) {
u32 dev, rev;
if (mvebu_get_soc_id(&dev, &rev) == 0 &&
rev == ARMADA_375_Z1_REV)
armada_375_coherency_init_wa();
}
bus_register_notifier(&platform_bus_type,
&mvebu_hwcc_nb);
return 0;
}
postcore_initcall(coherency_late_init);
#if IS_ENABLED(CONFIG_PCI)
static int __init coherency_pci_init(void)
{
if (coherency_available())
bus_register_notifier(&pci_bus_type,
&mvebu_hwcc_nb);
return 0;
}
arch_initcall(coherency_pci_init);
#endif
