u-boot/drivers/spi/rk_spi.c
Stephen Warren 135aa95002 clk: convert API to match reset/mailbox style
The following changes are made to the clock API:
* The concept of "clocks" and "peripheral clocks" are unified; each clock
  provider now implements a single set of clocks. This provides a simpler
  conceptual interface to clients, and better aligns with device tree
  clock bindings.
* Clocks are now identified with a single "struct clk", rather than
  requiring clients to store the clock provider device and clock identity
  values separately. For simple clock consumers, this isolates clients
  from internal details of the clock API.
* clk.h is split so it only contains the client/consumer API, whereas
  clk-uclass.h contains the provider API. This aligns with the recently
  added reset and mailbox APIs.
* clk_ops .of_xlate(), .request(), and .free() are added so providers
  can customize these operations if needed. This also aligns with the
  recently added reset and mailbox APIs.
* clk_disable() is added.
* All users of the current clock APIs are updated.
* Sandbox clock tests are updated to exercise clock lookup via DT, and
  clock enable/disable.
* rkclk_get_clk() is removed and replaced with standard APIs.

Buildman shows no clock-related errors for any board for which buildman
can download a toolchain.

test/py passes for sandbox (which invokes the dm clk test amongst
others).

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Simon Glass <sjg@chromium.org>
2016-06-19 17:05:55 -06:00

380 lines
9.3 KiB
C

/*
* spi driver for rockchip
*
* (C) Copyright 2015 Google, Inc
*
* (C) Copyright 2008-2013 Rockchip Electronics
* Peter, Software Engineering, <superpeter.cai@gmail.com>.
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <clk.h>
#include <dm.h>
#include <errno.h>
#include <spi.h>
#include <asm/errno.h>
#include <asm/io.h>
#include <asm/arch/clock.h>
#include <asm/arch/periph.h>
#include <dm/pinctrl.h>
#include "rk_spi.h"
DECLARE_GLOBAL_DATA_PTR;
/* Change to 1 to output registers at the start of each transaction */
#define DEBUG_RK_SPI 0
struct rockchip_spi_platdata {
s32 frequency; /* Default clock frequency, -1 for none */
fdt_addr_t base;
uint deactivate_delay_us; /* Delay to wait after deactivate */
uint activate_delay_us; /* Delay to wait after activate */
};
struct rockchip_spi_priv {
struct rockchip_spi *regs;
struct clk clk;
unsigned int max_freq;
unsigned int mode;
ulong last_transaction_us; /* Time of last transaction end */
u8 bits_per_word; /* max 16 bits per word */
u8 n_bytes;
unsigned int speed_hz;
unsigned int last_speed_hz;
unsigned int tmode;
uint input_rate;
};
#define SPI_FIFO_DEPTH 32
static void rkspi_dump_regs(struct rockchip_spi *regs)
{
debug("ctrl0: \t\t0x%08x\n", readl(&regs->ctrlr0));
debug("ctrl1: \t\t0x%08x\n", readl(&regs->ctrlr1));
debug("ssienr: \t\t0x%08x\n", readl(&regs->enr));
debug("ser: \t\t0x%08x\n", readl(&regs->ser));
debug("baudr: \t\t0x%08x\n", readl(&regs->baudr));
debug("txftlr: \t\t0x%08x\n", readl(&regs->txftlr));
debug("rxftlr: \t\t0x%08x\n", readl(&regs->rxftlr));
debug("txflr: \t\t0x%08x\n", readl(&regs->txflr));
debug("rxflr: \t\t0x%08x\n", readl(&regs->rxflr));
debug("sr: \t\t0x%08x\n", readl(&regs->sr));
debug("imr: \t\t0x%08x\n", readl(&regs->imr));
debug("isr: \t\t0x%08x\n", readl(&regs->isr));
debug("dmacr: \t\t0x%08x\n", readl(&regs->dmacr));
debug("dmatdlr: \t0x%08x\n", readl(&regs->dmatdlr));
debug("dmardlr: \t0x%08x\n", readl(&regs->dmardlr));
}
static void rkspi_enable_chip(struct rockchip_spi *regs, bool enable)
{
writel(enable ? 1 : 0, &regs->enr);
}
static void rkspi_set_clk(struct rockchip_spi_priv *priv, uint speed)
{
uint clk_div;
clk_div = clk_get_divisor(priv->input_rate, speed);
debug("spi speed %u, div %u\n", speed, clk_div);
writel(clk_div, &priv->regs->baudr);
priv->last_speed_hz = speed;
}
static int rkspi_wait_till_not_busy(struct rockchip_spi *regs)
{
unsigned long start;
start = get_timer(0);
while (readl(&regs->sr) & SR_BUSY) {
if (get_timer(start) > ROCKCHIP_SPI_TIMEOUT_MS) {
debug("RK SPI: Status keeps busy for 1000us after a read/write!\n");
return -ETIMEDOUT;
}
}
return 0;
}
static void spi_cs_activate(struct udevice *dev, uint cs)
{
struct udevice *bus = dev->parent;
struct rockchip_spi_platdata *plat = bus->platdata;
struct rockchip_spi_priv *priv = dev_get_priv(bus);
struct rockchip_spi *regs = priv->regs;
debug("activate cs%u\n", cs);
writel(1 << cs, &regs->ser);
if (plat->activate_delay_us)
udelay(plat->activate_delay_us);
}
static void spi_cs_deactivate(struct udevice *dev, uint cs)
{
struct udevice *bus = dev->parent;
struct rockchip_spi_platdata *plat = bus->platdata;
struct rockchip_spi_priv *priv = dev_get_priv(bus);
struct rockchip_spi *regs = priv->regs;
debug("deactivate cs%u\n", cs);
writel(0, &regs->ser);
/* Remember time of this transaction so we can honour the bus delay */
if (plat->deactivate_delay_us)
priv->last_transaction_us = timer_get_us();
}
static int rockchip_spi_ofdata_to_platdata(struct udevice *bus)
{
struct rockchip_spi_platdata *plat = bus->platdata;
struct rockchip_spi_priv *priv = dev_get_priv(bus);
const void *blob = gd->fdt_blob;
int node = bus->of_offset;
int ret;
plat->base = dev_get_addr(bus);
ret = clk_get_by_index(bus, 0, &priv->clk);
if (ret < 0) {
debug("%s: Could not get clock for %s: %d\n", __func__,
bus->name, ret);
return ret;
}
plat->frequency = fdtdec_get_int(blob, node, "spi-max-frequency",
50000000);
plat->deactivate_delay_us = fdtdec_get_int(blob, node,
"spi-deactivate-delay", 0);
plat->activate_delay_us = fdtdec_get_int(blob, node,
"spi-activate-delay", 0);
debug("%s: base=%x, max-frequency=%d, deactivate_delay=%d\n",
__func__, (uint)plat->base, plat->frequency,
plat->deactivate_delay_us);
return 0;
}
static int rockchip_spi_probe(struct udevice *bus)
{
struct rockchip_spi_platdata *plat = dev_get_platdata(bus);
struct rockchip_spi_priv *priv = dev_get_priv(bus);
int ret;
debug("%s: probe\n", __func__);
priv->regs = (struct rockchip_spi *)plat->base;
priv->last_transaction_us = timer_get_us();
priv->max_freq = plat->frequency;
/*
* Use 99 MHz as our clock since it divides nicely into 594 MHz which
* is the assumed speed for CLK_GENERAL.
*/
ret = clk_set_rate(&priv->clk, 99000000);
if (ret < 0) {
debug("%s: Failed to set clock: %d\n", __func__, ret);
return ret;
}
priv->input_rate = ret;
debug("%s: rate = %u\n", __func__, priv->input_rate);
priv->bits_per_word = 8;
priv->tmode = TMOD_TR; /* Tx & Rx */
return 0;
}
static int rockchip_spi_claim_bus(struct udevice *dev)
{
struct udevice *bus = dev->parent;
struct rockchip_spi_priv *priv = dev_get_priv(bus);
struct rockchip_spi *regs = priv->regs;
u8 spi_dfs, spi_tf;
uint ctrlr0;
/* Disable the SPI hardware */
rkspi_enable_chip(regs, 0);
switch (priv->bits_per_word) {
case 8:
priv->n_bytes = 1;
spi_dfs = DFS_8BIT;
spi_tf = HALF_WORD_OFF;
break;
case 16:
priv->n_bytes = 2;
spi_dfs = DFS_16BIT;
spi_tf = HALF_WORD_ON;
break;
default:
debug("%s: unsupported bits: %dbits\n", __func__,
priv->bits_per_word);
return -EPROTONOSUPPORT;
}
if (priv->speed_hz != priv->last_speed_hz)
rkspi_set_clk(priv, priv->speed_hz);
/* Operation Mode */
ctrlr0 = OMOD_MASTER << OMOD_SHIFT;
/* Data Frame Size */
ctrlr0 |= spi_dfs << DFS_SHIFT;
/* set SPI mode 0..3 */
if (priv->mode & SPI_CPOL)
ctrlr0 |= SCOL_HIGH << SCOL_SHIFT;
if (priv->mode & SPI_CPHA)
ctrlr0 |= SCPH_TOGSTA << SCPH_SHIFT;
/* Chip Select Mode */
ctrlr0 |= CSM_KEEP << CSM_SHIFT;
/* SSN to Sclk_out delay */
ctrlr0 |= SSN_DELAY_ONE << SSN_DELAY_SHIFT;
/* Serial Endian Mode */
ctrlr0 |= SEM_LITTLE << SEM_SHIFT;
/* First Bit Mode */
ctrlr0 |= FBM_MSB << FBM_SHIFT;
/* Byte and Halfword Transform */
ctrlr0 |= spi_tf << HALF_WORD_TX_SHIFT;
/* Rxd Sample Delay */
ctrlr0 |= 0 << RXDSD_SHIFT;
/* Frame Format */
ctrlr0 |= FRF_SPI << FRF_SHIFT;
/* Tx and Rx mode */
ctrlr0 |= (priv->tmode & TMOD_MASK) << TMOD_SHIFT;
writel(ctrlr0, &regs->ctrlr0);
return 0;
}
static int rockchip_spi_release_bus(struct udevice *dev)
{
struct udevice *bus = dev->parent;
struct rockchip_spi_priv *priv = dev_get_priv(bus);
rkspi_enable_chip(priv->regs, false);
return 0;
}
static int rockchip_spi_xfer(struct udevice *dev, unsigned int bitlen,
const void *dout, void *din, unsigned long flags)
{
struct udevice *bus = dev->parent;
struct rockchip_spi_priv *priv = dev_get_priv(bus);
struct rockchip_spi *regs = priv->regs;
struct dm_spi_slave_platdata *slave_plat = dev_get_parent_platdata(dev);
int len = bitlen >> 3;
const u8 *out = dout;
u8 *in = din;
int toread, towrite;
int ret;
debug("%s: dout=%p, din=%p, len=%x, flags=%lx\n", __func__, dout, din,
len, flags);
if (DEBUG_RK_SPI)
rkspi_dump_regs(regs);
/* Assert CS before transfer */
if (flags & SPI_XFER_BEGIN)
spi_cs_activate(dev, slave_plat->cs);
while (len > 0) {
int todo = min(len, 0xffff);
rkspi_enable_chip(regs, false);
writel(todo - 1, &regs->ctrlr1);
rkspi_enable_chip(regs, true);
toread = todo;
towrite = todo;
while (toread || towrite) {
u32 status = readl(&regs->sr);
if (towrite && !(status & SR_TF_FULL)) {
writel(out ? *out++ : 0, regs->txdr);
towrite--;
}
if (toread && !(status & SR_RF_EMPT)) {
u32 byte = readl(regs->rxdr);
if (in)
*in++ = byte;
toread--;
}
}
ret = rkspi_wait_till_not_busy(regs);
if (ret)
break;
len -= todo;
}
/* Deassert CS after transfer */
if (flags & SPI_XFER_END)
spi_cs_deactivate(dev, slave_plat->cs);
rkspi_enable_chip(regs, false);
return ret;
}
static int rockchip_spi_set_speed(struct udevice *bus, uint speed)
{
struct rockchip_spi_priv *priv = dev_get_priv(bus);
if (speed > ROCKCHIP_SPI_MAX_RATE)
return -EINVAL;
if (speed > priv->max_freq)
speed = priv->max_freq;
priv->speed_hz = speed;
return 0;
}
static int rockchip_spi_set_mode(struct udevice *bus, uint mode)
{
struct rockchip_spi_priv *priv = dev_get_priv(bus);
priv->mode = mode;
return 0;
}
static const struct dm_spi_ops rockchip_spi_ops = {
.claim_bus = rockchip_spi_claim_bus,
.release_bus = rockchip_spi_release_bus,
.xfer = rockchip_spi_xfer,
.set_speed = rockchip_spi_set_speed,
.set_mode = rockchip_spi_set_mode,
/*
* cs_info is not needed, since we require all chip selects to be
* in the device tree explicitly
*/
};
static const struct udevice_id rockchip_spi_ids[] = {
{ .compatible = "rockchip,rk3288-spi" },
{ }
};
U_BOOT_DRIVER(rockchip_spi) = {
.name = "rockchip_spi",
.id = UCLASS_SPI,
.of_match = rockchip_spi_ids,
.ops = &rockchip_spi_ops,
.ofdata_to_platdata = rockchip_spi_ofdata_to_platdata,
.platdata_auto_alloc_size = sizeof(struct rockchip_spi_platdata),
.priv_auto_alloc_size = sizeof(struct rockchip_spi_priv),
.probe = rockchip_spi_probe,
};