u-boot/drivers/misc/p2sb-uclass.c
Simon Glass 5bee27aa41 pci: Add support for p2sb uclass
The Primary-to-Sideband bus (P2SB) is used to access various peripherals
through memory-mapped I/O in a large chunk of PCI space. The space is
segmented into different channels and peripherals are accessed by
device-specific means within those channels. Devices should be added in
the device tree as subnodes of the p2sb.

This adds a uclass and enables it for sandbox.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
2019-12-15 11:44:11 +08:00

216 lines
5.1 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Uclass for Primary-to-sideband bus, used to access various peripherals
*
* Copyright 2019 Google LLC
* Written by Simon Glass <sjg@chromium.org>
*/
#include <common.h>
#include <dm.h>
#include <mapmem.h>
#include <p2sb.h>
#include <spl.h>
#include <asm/io.h>
#include <dm/uclass-internal.h>
#define PCR_COMMON_IOSF_1_0 1
static void *_pcr_reg_address(struct udevice *dev, uint offset)
{
struct p2sb_child_platdata *pplat = dev_get_parent_platdata(dev);
struct udevice *p2sb = dev_get_parent(dev);
struct p2sb_uc_priv *upriv = dev_get_uclass_priv(p2sb);
uintptr_t reg_addr;
/* Create an address based off of port id and offset */
reg_addr = upriv->mmio_base;
reg_addr += pplat->pid << PCR_PORTID_SHIFT;
reg_addr += offset;
return map_sysmem(reg_addr, 4);
}
/*
* The mapping of addresses via the SBREG_BAR assumes the IOSF-SB
* agents are using 32-bit aligned accesses for their configuration
* registers. For IOSF versions greater than 1_0, IOSF-SB
* agents can use any access (8/16/32 bit aligned) for their
* configuration registers
*/
static inline void check_pcr_offset_align(uint offset, uint size)
{
const size_t align = PCR_COMMON_IOSF_1_0 ? sizeof(uint32_t) : size;
assert(IS_ALIGNED(offset, align));
}
uint pcr_read32(struct udevice *dev, uint offset)
{
void *ptr;
uint val;
/* Ensure the PCR offset is correctly aligned */
assert(IS_ALIGNED(offset, sizeof(uint32_t)));
ptr = _pcr_reg_address(dev, offset);
val = readl(ptr);
unmap_sysmem(ptr);
return val;
}
uint pcr_read16(struct udevice *dev, uint offset)
{
/* Ensure the PCR offset is correctly aligned */
check_pcr_offset_align(offset, sizeof(uint16_t));
return readw(_pcr_reg_address(dev, offset));
}
uint pcr_read8(struct udevice *dev, uint offset)
{
/* Ensure the PCR offset is correctly aligned */
check_pcr_offset_align(offset, sizeof(uint8_t));
return readb(_pcr_reg_address(dev, offset));
}
/*
* After every write one needs to perform a read an innocuous register to
* ensure the writes are completed for certain ports. This is done for
* all ports so that the callers don't need the per-port knowledge for
* each transaction.
*/
static void write_completion(struct udevice *dev, uint offset)
{
readl(_pcr_reg_address(dev, ALIGN_DOWN(offset, sizeof(uint32_t))));
}
void pcr_write32(struct udevice *dev, uint offset, uint indata)
{
/* Ensure the PCR offset is correctly aligned */
assert(IS_ALIGNED(offset, sizeof(indata)));
writel(indata, _pcr_reg_address(dev, offset));
/* Ensure the writes complete */
write_completion(dev, offset);
}
void pcr_write16(struct udevice *dev, uint offset, uint indata)
{
/* Ensure the PCR offset is correctly aligned */
check_pcr_offset_align(offset, sizeof(uint16_t));
writew(indata, _pcr_reg_address(dev, offset));
/* Ensure the writes complete */
write_completion(dev, offset);
}
void pcr_write8(struct udevice *dev, uint offset, uint indata)
{
/* Ensure the PCR offset is correctly aligned */
check_pcr_offset_align(offset, sizeof(uint8_t));
writeb(indata, _pcr_reg_address(dev, offset));
/* Ensure the writes complete */
write_completion(dev, offset);
}
void pcr_clrsetbits32(struct udevice *dev, uint offset, uint clr, uint set)
{
uint data32;
data32 = pcr_read32(dev, offset);
data32 &= ~clr;
data32 |= set;
pcr_write32(dev, offset, data32);
}
void pcr_clrsetbits16(struct udevice *dev, uint offset, uint clr, uint set)
{
uint data16;
data16 = pcr_read16(dev, offset);
data16 &= ~clr;
data16 |= set;
pcr_write16(dev, offset, data16);
}
void pcr_clrsetbits8(struct udevice *dev, uint offset, uint clr, uint set)
{
uint data8;
data8 = pcr_read8(dev, offset);
data8 &= ~clr;
data8 |= set;
pcr_write8(dev, offset, data8);
}
int p2sb_get_port_id(struct udevice *dev)
{
struct p2sb_child_platdata *pplat = dev_get_parent_platdata(dev);
return pplat->pid;
}
int p2sb_set_port_id(struct udevice *dev, int portid)
{
struct udevice *ps2b;
struct p2sb_child_platdata *pplat;
if (!CONFIG_IS_ENABLED(OF_PLATDATA))
return -ENOSYS;
uclass_find_first_device(UCLASS_P2SB, &ps2b);
if (!ps2b)
return -EDEADLK;
dev->parent = ps2b;
/*
* We must allocate this, since when the device was bound it did not
* have a parent.
* TODO(sjg@chromium.org): Add a parent pointer to child devices in dtoc
*/
dev->parent_platdata = malloc(sizeof(*pplat));
if (!dev->parent_platdata)
return -ENOMEM;
pplat = dev_get_parent_platdata(dev);
pplat->pid = portid;
return 0;
}
static int p2sb_child_post_bind(struct udevice *dev)
{
#if !CONFIG_IS_ENABLED(OF_PLATDATA)
struct p2sb_child_platdata *pplat = dev_get_parent_platdata(dev);
int ret;
u32 pid;
ret = dev_read_u32(dev, "intel,p2sb-port-id", &pid);
if (ret)
return ret;
pplat->pid = pid;
#endif
return 0;
}
static int p2sb_post_bind(struct udevice *dev)
{
if (spl_phase() > PHASE_TPL && !CONFIG_IS_ENABLED(OF_PLATDATA))
return dm_scan_fdt_dev(dev);
return 0;
}
UCLASS_DRIVER(p2sb) = {
.id = UCLASS_P2SB,
.name = "p2sb",
.per_device_auto_alloc_size = sizeof(struct p2sb_uc_priv),
.post_bind = p2sb_post_bind,
.child_post_bind = p2sb_child_post_bind,
.per_child_platdata_auto_alloc_size =
sizeof(struct p2sb_child_platdata),
};