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linux/drivers/clk/clk-aspeed.c
Andrew Jeffery 801b787a69 clk: aspeed: Add RMII RCLK gates for both AST2500 MACs 
RCLK is a fixed 50MHz clock derived from HPLL that is described by a
single gate for each MAC.

Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Link: https://lkml.kernel.org/r/20191010020655.3776-3-andrew@aj.id.au
Reviewed-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2019-11-26 10:02:48 -08:00

743 lines
20 KiB
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// SPDX-License-Identifier: GPL-2.0+
// Copyright IBM Corp
#define pr_fmt(fmt) "clk-aspeed: " fmt
#include <linux/mfd/syscon.h>
#include <linux/of_address.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/slab.h>
#include <dt-bindings/clock/aspeed-clock.h>
#include "clk-aspeed.h"
#define ASPEED_NUM_CLKS 38
#define ASPEED_RESET2_OFFSET 32
#define ASPEED_RESET_CTRL 0x04
#define ASPEED_CLK_SELECTION 0x08
#define ASPEED_CLK_STOP_CTRL 0x0c
#define ASPEED_MPLL_PARAM 0x20
#define ASPEED_HPLL_PARAM 0x24
#define AST2500_HPLL_BYPASS_EN BIT(20)
#define AST2400_HPLL_PROGRAMMED BIT(18)
#define AST2400_HPLL_BYPASS_EN BIT(17)
#define ASPEED_MISC_CTRL 0x2c
#define UART_DIV13_EN BIT(12)
#define ASPEED_MAC_CLK_DLY 0x48
#define ASPEED_STRAP 0x70
#define CLKIN_25MHZ_EN BIT(23)
#define AST2400_CLK_SOURCE_SEL BIT(18)
#define ASPEED_CLK_SELECTION_2 0xd8
#define ASPEED_RESET_CTRL2 0xd4
/* Globally visible clocks */
static DEFINE_SPINLOCK(aspeed_clk_lock);
/* Keeps track of all clocks */
static struct clk_hw_onecell_data *aspeed_clk_data;
static void __iomem *scu_base;
/* TODO: ask Aspeed about the actual parent data */
static const struct aspeed_gate_data aspeed_gates[] = {
/* clk rst name parent flags */
[ASPEED_CLK_GATE_ECLK] = { 0, 6, "eclk-gate", "eclk", 0 }, /* Video Engine */
[ASPEED_CLK_GATE_GCLK] = { 1, 7, "gclk-gate", NULL, 0 }, /* 2D engine */
[ASPEED_CLK_GATE_MCLK] = { 2, -1, "mclk-gate", "mpll", CLK_IS_CRITICAL }, /* SDRAM */
[ASPEED_CLK_GATE_VCLK] = { 3, -1, "vclk-gate", NULL, 0 }, /* Video Capture */
[ASPEED_CLK_GATE_BCLK] = { 4, 8, "bclk-gate", "bclk", CLK_IS_CRITICAL }, /* PCIe/PCI */
[ASPEED_CLK_GATE_DCLK] = { 5, -1, "dclk-gate", NULL, CLK_IS_CRITICAL }, /* DAC */
[ASPEED_CLK_GATE_REFCLK] = { 6, -1, "refclk-gate", "clkin", CLK_IS_CRITICAL },
[ASPEED_CLK_GATE_USBPORT2CLK] = { 7, 3, "usb-port2-gate", NULL, 0 }, /* USB2.0 Host port 2 */
[ASPEED_CLK_GATE_LCLK] = { 8, 5, "lclk-gate", NULL, 0 }, /* LPC */
[ASPEED_CLK_GATE_USBUHCICLK] = { 9, 15, "usb-uhci-gate", NULL, 0 }, /* USB1.1 (requires port 2 enabled) */
[ASPEED_CLK_GATE_D1CLK] = { 10, 13, "d1clk-gate", NULL, 0 }, /* GFX CRT */
[ASPEED_CLK_GATE_YCLK] = { 13, 4, "yclk-gate", NULL, 0 }, /* HAC */
[ASPEED_CLK_GATE_USBPORT1CLK] = { 14, 14, "usb-port1-gate", NULL, 0 }, /* USB2 hub/USB2 host port 1/USB1.1 dev */
[ASPEED_CLK_GATE_UART1CLK] = { 15, -1, "uart1clk-gate", "uart", 0 }, /* UART1 */
[ASPEED_CLK_GATE_UART2CLK] = { 16, -1, "uart2clk-gate", "uart", 0 }, /* UART2 */
[ASPEED_CLK_GATE_UART5CLK] = { 17, -1, "uart5clk-gate", "uart", 0 }, /* UART5 */
[ASPEED_CLK_GATE_ESPICLK] = { 19, -1, "espiclk-gate", NULL, 0 }, /* eSPI */
[ASPEED_CLK_GATE_MAC1CLK] = { 20, 11, "mac1clk-gate", "mac", 0 }, /* MAC1 */
[ASPEED_CLK_GATE_MAC2CLK] = { 21, 12, "mac2clk-gate", "mac", 0 }, /* MAC2 */
[ASPEED_CLK_GATE_RSACLK] = { 24, -1, "rsaclk-gate", NULL, 0 }, /* RSA */
[ASPEED_CLK_GATE_UART3CLK] = { 25, -1, "uart3clk-gate", "uart", 0 }, /* UART3 */
[ASPEED_CLK_GATE_UART4CLK] = { 26, -1, "uart4clk-gate", "uart", 0 }, /* UART4 */
[ASPEED_CLK_GATE_SDCLK] = { 27, 16, "sdclk-gate", NULL, 0 }, /* SDIO/SD */
[ASPEED_CLK_GATE_LHCCLK] = { 28, -1, "lhclk-gate", "lhclk", 0 }, /* LPC master/LPC+ */
};
static const char * const eclk_parent_names[] = {
"mpll",
"hpll",
"dpll",
};
static const struct clk_div_table ast2500_eclk_div_table[] = {
{ 0x0, 2 },
{ 0x1, 2 },
{ 0x2, 3 },
{ 0x3, 4 },
{ 0x4, 5 },
{ 0x5, 6 },
{ 0x6, 7 },
{ 0x7, 8 },
{ 0 }
};
static const struct clk_div_table ast2500_mac_div_table[] = {
{ 0x0, 4 }, /* Yep, really. Aspeed confirmed this is correct */
{ 0x1, 4 },
{ 0x2, 6 },
{ 0x3, 8 },
{ 0x4, 10 },
{ 0x5, 12 },
{ 0x6, 14 },
{ 0x7, 16 },
{ 0 }
};
static const struct clk_div_table ast2400_div_table[] = {
{ 0x0, 2 },
{ 0x1, 4 },
{ 0x2, 6 },
{ 0x3, 8 },
{ 0x4, 10 },
{ 0x5, 12 },
{ 0x6, 14 },
{ 0x7, 16 },
{ 0 }
};
static const struct clk_div_table ast2500_div_table[] = {
{ 0x0, 4 },
{ 0x1, 8 },
{ 0x2, 12 },
{ 0x3, 16 },
{ 0x4, 20 },
{ 0x5, 24 },
{ 0x6, 28 },
{ 0x7, 32 },
{ 0 }
};
static struct clk_hw *aspeed_ast2400_calc_pll(const char *name, u32 val)
{
unsigned int mult, div;
if (val & AST2400_HPLL_BYPASS_EN) {
/* Pass through mode */
mult = div = 1;
} else {
/* F = 24Mhz * (2-OD) * [(N + 2) / (D + 1)] */
u32 n = (val >> 5) & 0x3f;
u32 od = (val >> 4) & 0x1;
u32 d = val & 0xf;
mult = (2 - od) * (n + 2);
div = d + 1;
}
return clk_hw_register_fixed_factor(NULL, name, "clkin", 0,
mult, div);
};
static struct clk_hw *aspeed_ast2500_calc_pll(const char *name, u32 val)
{
unsigned int mult, div;
if (val & AST2500_HPLL_BYPASS_EN) {
/* Pass through mode */
mult = div = 1;
} else {
/* F = clkin * [(M+1) / (N+1)] / (P + 1) */
u32 p = (val >> 13) & 0x3f;
u32 m = (val >> 5) & 0xff;
u32 n = val & 0x1f;
mult = (m + 1) / (n + 1);
div = p + 1;
}
return clk_hw_register_fixed_factor(NULL, name, "clkin", 0,
mult, div);
}
static const struct aspeed_clk_soc_data ast2500_data = {
.div_table = ast2500_div_table,
.eclk_div_table = ast2500_eclk_div_table,
.mac_div_table = ast2500_mac_div_table,
.calc_pll = aspeed_ast2500_calc_pll,
};
static const struct aspeed_clk_soc_data ast2400_data = {
.div_table = ast2400_div_table,
.eclk_div_table = ast2400_div_table,
.mac_div_table = ast2400_div_table,
.calc_pll = aspeed_ast2400_calc_pll,
};
static int aspeed_clk_is_enabled(struct clk_hw *hw)
{
struct aspeed_clk_gate *gate = to_aspeed_clk_gate(hw);
u32 clk = BIT(gate->clock_idx);
u32 rst = BIT(gate->reset_idx);
u32 enval = (gate->flags & CLK_GATE_SET_TO_DISABLE) ? 0 : clk;
u32 reg;
/*
* If the IP is in reset, treat the clock as not enabled,
* this happens with some clocks such as the USB one when
* coming from cold reset. Without this, aspeed_clk_enable()
* will fail to lift the reset.
*/
if (gate->reset_idx >= 0) {
regmap_read(gate->map, ASPEED_RESET_CTRL, &reg);
if (reg & rst)
return 0;
}
regmap_read(gate->map, ASPEED_CLK_STOP_CTRL, &reg);
return ((reg & clk) == enval) ? 1 : 0;
}
static int aspeed_clk_enable(struct clk_hw *hw)
{
struct aspeed_clk_gate *gate = to_aspeed_clk_gate(hw);
unsigned long flags;
u32 clk = BIT(gate->clock_idx);
u32 rst = BIT(gate->reset_idx);
u32 enval;
spin_lock_irqsave(gate->lock, flags);
if (aspeed_clk_is_enabled(hw)) {
spin_unlock_irqrestore(gate->lock, flags);
return 0;
}
if (gate->reset_idx >= 0) {
/* Put IP in reset */
regmap_update_bits(gate->map, ASPEED_RESET_CTRL, rst, rst);
/* Delay 100us */
udelay(100);
}
/* Enable clock */
enval = (gate->flags & CLK_GATE_SET_TO_DISABLE) ? 0 : clk;
regmap_update_bits(gate->map, ASPEED_CLK_STOP_CTRL, clk, enval);
if (gate->reset_idx >= 0) {
/* A delay of 10ms is specified by the ASPEED docs */
mdelay(10);
/* Take IP out of reset */
regmap_update_bits(gate->map, ASPEED_RESET_CTRL, rst, 0);
}
spin_unlock_irqrestore(gate->lock, flags);
return 0;
}
static void aspeed_clk_disable(struct clk_hw *hw)
{
struct aspeed_clk_gate *gate = to_aspeed_clk_gate(hw);
unsigned long flags;
u32 clk = BIT(gate->clock_idx);
u32 enval;
spin_lock_irqsave(gate->lock, flags);
enval = (gate->flags & CLK_GATE_SET_TO_DISABLE) ? clk : 0;
regmap_update_bits(gate->map, ASPEED_CLK_STOP_CTRL, clk, enval);
spin_unlock_irqrestore(gate->lock, flags);
}
static const struct clk_ops aspeed_clk_gate_ops = {
.enable = aspeed_clk_enable,
.disable = aspeed_clk_disable,
.is_enabled = aspeed_clk_is_enabled,
};
static const u8 aspeed_resets[] = {
/* SCU04 resets */
[ASPEED_RESET_XDMA] = 25,
[ASPEED_RESET_MCTP] = 24,
[ASPEED_RESET_ADC] = 23,
[ASPEED_RESET_JTAG_MASTER] = 22,
[ASPEED_RESET_MIC] = 18,
[ASPEED_RESET_PWM] = 9,
[ASPEED_RESET_PECI] = 10,
[ASPEED_RESET_I2C] = 2,
[ASPEED_RESET_AHB] = 1,
/*
* SCUD4 resets start at an offset to separate them from
* the SCU04 resets.
*/
[ASPEED_RESET_CRT1] = ASPEED_RESET2_OFFSET + 5,
};
static int aspeed_reset_deassert(struct reset_controller_dev *rcdev,
unsigned long id)
{
struct aspeed_reset *ar = to_aspeed_reset(rcdev);
u32 reg = ASPEED_RESET_CTRL;
u32 bit = aspeed_resets[id];
if (bit >= ASPEED_RESET2_OFFSET) {
bit -= ASPEED_RESET2_OFFSET;
reg = ASPEED_RESET_CTRL2;
}
return regmap_update_bits(ar->map, reg, BIT(bit), 0);
}
static int aspeed_reset_assert(struct reset_controller_dev *rcdev,
unsigned long id)
{
struct aspeed_reset *ar = to_aspeed_reset(rcdev);
u32 reg = ASPEED_RESET_CTRL;
u32 bit = aspeed_resets[id];
if (bit >= ASPEED_RESET2_OFFSET) {
bit -= ASPEED_RESET2_OFFSET;
reg = ASPEED_RESET_CTRL2;
}
return regmap_update_bits(ar->map, reg, BIT(bit), BIT(bit));
}
static int aspeed_reset_status(struct reset_controller_dev *rcdev,
unsigned long id)
{
struct aspeed_reset *ar = to_aspeed_reset(rcdev);
u32 reg = ASPEED_RESET_CTRL;
u32 bit = aspeed_resets[id];
int ret, val;
if (bit >= ASPEED_RESET2_OFFSET) {
bit -= ASPEED_RESET2_OFFSET;
reg = ASPEED_RESET_CTRL2;
}
ret = regmap_read(ar->map, reg, &val);
if (ret)
return ret;
return !!(val & BIT(bit));
}
static const struct reset_control_ops aspeed_reset_ops = {
.assert = aspeed_reset_assert,
.deassert = aspeed_reset_deassert,
.status = aspeed_reset_status,
};
static struct clk_hw *aspeed_clk_hw_register_gate(struct device *dev,
const char *name, const char *parent_name, unsigned long flags,
struct regmap *map, u8 clock_idx, u8 reset_idx,
u8 clk_gate_flags, spinlock_t *lock)
{
struct aspeed_clk_gate *gate;
struct clk_init_data init;
struct clk_hw *hw;
int ret;
gate = kzalloc(sizeof(*gate), GFP_KERNEL);
if (!gate)
return ERR_PTR(-ENOMEM);
init.name = name;
init.ops = &aspeed_clk_gate_ops;
init.flags = flags;
init.parent_names = parent_name ? &parent_name : NULL;
init.num_parents = parent_name ? 1 : 0;
gate->map = map;
gate->clock_idx = clock_idx;
gate->reset_idx = reset_idx;
gate->flags = clk_gate_flags;
gate->lock = lock;
gate->hw.init = &init;
hw = &gate->hw;
ret = clk_hw_register(dev, hw);
if (ret) {
kfree(gate);
hw = ERR_PTR(ret);
}
return hw;
}
static int aspeed_clk_probe(struct platform_device *pdev)
{
const struct aspeed_clk_soc_data *soc_data;
struct device *dev = &pdev->dev;
struct aspeed_reset *ar;
struct regmap *map;
struct clk_hw *hw;
u32 val, rate;
int i, ret;
map = syscon_node_to_regmap(dev->of_node);
if (IS_ERR(map)) {
dev_err(dev, "no syscon regmap\n");
return PTR_ERR(map);
}
ar = devm_kzalloc(dev, sizeof(*ar), GFP_KERNEL);
if (!ar)
return -ENOMEM;
ar->map = map;
ar->rcdev.owner = THIS_MODULE;
ar->rcdev.nr_resets = ARRAY_SIZE(aspeed_resets);
ar->rcdev.ops = &aspeed_reset_ops;
ar->rcdev.of_node = dev->of_node;
ret = devm_reset_controller_register(dev, &ar->rcdev);
if (ret) {
dev_err(dev, "could not register reset controller\n");
return ret;
}
/* SoC generations share common layouts but have different divisors */
soc_data = of_device_get_match_data(dev);
if (!soc_data) {
dev_err(dev, "no match data for platform\n");
return -EINVAL;
}
/* UART clock div13 setting */
regmap_read(map, ASPEED_MISC_CTRL, &val);
if (val & UART_DIV13_EN)
rate = 24000000 / 13;
else
rate = 24000000;
/* TODO: Find the parent data for the uart clock */
hw = clk_hw_register_fixed_rate(dev, "uart", NULL, 0, rate);
if (IS_ERR(hw))
return PTR_ERR(hw);
aspeed_clk_data->hws[ASPEED_CLK_UART] = hw;
/*
* Memory controller (M-PLL) PLL. This clock is configured by the
* bootloader, and is exposed to Linux as a read-only clock rate.
*/
regmap_read(map, ASPEED_MPLL_PARAM, &val);
hw = soc_data->calc_pll("mpll", val);
if (IS_ERR(hw))
return PTR_ERR(hw);
aspeed_clk_data->hws[ASPEED_CLK_MPLL] = hw;
/* SD/SDIO clock divider and gate */
hw = clk_hw_register_gate(dev, "sd_extclk_gate", "hpll", 0,
scu_base + ASPEED_CLK_SELECTION, 15, 0,
&aspeed_clk_lock);
if (IS_ERR(hw))
return PTR_ERR(hw);
hw = clk_hw_register_divider_table(dev, "sd_extclk", "sd_extclk_gate",
0, scu_base + ASPEED_CLK_SELECTION, 12, 3, 0,
soc_data->div_table,
&aspeed_clk_lock);
if (IS_ERR(hw))
return PTR_ERR(hw);
aspeed_clk_data->hws[ASPEED_CLK_SDIO] = hw;
/* MAC AHB bus clock divider */
hw = clk_hw_register_divider_table(dev, "mac", "hpll", 0,
scu_base + ASPEED_CLK_SELECTION, 16, 3, 0,
soc_data->mac_div_table,
&aspeed_clk_lock);
if (IS_ERR(hw))
return PTR_ERR(hw);
aspeed_clk_data->hws[ASPEED_CLK_MAC] = hw;
if (of_device_is_compatible(pdev->dev.of_node, "aspeed,ast2500-scu")) {
/* RMII 50MHz RCLK */
hw = clk_hw_register_fixed_rate(dev, "mac12rclk", "hpll", 0,
50000000);
if (IS_ERR(hw))
return PTR_ERR(hw);
/* RMII1 50MHz (RCLK) output enable */
hw = clk_hw_register_gate(dev, "mac1rclk", "mac12rclk", 0,
scu_base + ASPEED_MAC_CLK_DLY, 29, 0,
&aspeed_clk_lock);
if (IS_ERR(hw))
return PTR_ERR(hw);
aspeed_clk_data->hws[ASPEED_CLK_MAC1RCLK] = hw;
/* RMII2 50MHz (RCLK) output enable */
hw = clk_hw_register_gate(dev, "mac2rclk", "mac12rclk", 0,
scu_base + ASPEED_MAC_CLK_DLY, 30, 0,
&aspeed_clk_lock);
if (IS_ERR(hw))
return PTR_ERR(hw);
aspeed_clk_data->hws[ASPEED_CLK_MAC2RCLK] = hw;
}
/* LPC Host (LHCLK) clock divider */
hw = clk_hw_register_divider_table(dev, "lhclk", "hpll", 0,
scu_base + ASPEED_CLK_SELECTION, 20, 3, 0,
soc_data->div_table,
&aspeed_clk_lock);
if (IS_ERR(hw))
return PTR_ERR(hw);
aspeed_clk_data->hws[ASPEED_CLK_LHCLK] = hw;
/* P-Bus (BCLK) clock divider */
hw = clk_hw_register_divider_table(dev, "bclk", "hpll", 0,
scu_base + ASPEED_CLK_SELECTION_2, 0, 2, 0,
soc_data->div_table,
&aspeed_clk_lock);
if (IS_ERR(hw))
return PTR_ERR(hw);
aspeed_clk_data->hws[ASPEED_CLK_BCLK] = hw;
/* Fixed 24MHz clock */
hw = clk_hw_register_fixed_rate(NULL, "fixed-24m", "clkin",
0, 24000000);
if (IS_ERR(hw))
return PTR_ERR(hw);
aspeed_clk_data->hws[ASPEED_CLK_24M] = hw;
hw = clk_hw_register_mux(dev, "eclk-mux", eclk_parent_names,
ARRAY_SIZE(eclk_parent_names), 0,
scu_base + ASPEED_CLK_SELECTION, 2, 0x3, 0,
&aspeed_clk_lock);
if (IS_ERR(hw))
return PTR_ERR(hw);
aspeed_clk_data->hws[ASPEED_CLK_ECLK_MUX] = hw;
hw = clk_hw_register_divider_table(dev, "eclk", "eclk-mux", 0,
scu_base + ASPEED_CLK_SELECTION, 28,
3, 0, soc_data->eclk_div_table,
&aspeed_clk_lock);
if (IS_ERR(hw))
return PTR_ERR(hw);
aspeed_clk_data->hws[ASPEED_CLK_ECLK] = hw;
/*
* TODO: There are a number of clocks that not included in this driver
* as more information is required:
* D2-PLL
* D-PLL
* YCLK
* RGMII
* RMII
* UART[1..5] clock source mux
*/
for (i = 0; i < ARRAY_SIZE(aspeed_gates); i++) {
const struct aspeed_gate_data *gd = &aspeed_gates[i];
u32 gate_flags;
/* Special case: the USB port 1 clock (bit 14) is always
* working the opposite way from the other ones.
*/
gate_flags = (gd->clock_idx == 14) ? 0 : CLK_GATE_SET_TO_DISABLE;
hw = aspeed_clk_hw_register_gate(dev,
gd->name,
gd->parent_name,
gd->flags,
map,
gd->clock_idx,
gd->reset_idx,
gate_flags,
&aspeed_clk_lock);
if (IS_ERR(hw))
return PTR_ERR(hw);
aspeed_clk_data->hws[i] = hw;
}
return 0;
};
static const struct of_device_id aspeed_clk_dt_ids[] = {
{ .compatible = "aspeed,ast2400-scu", .data = &ast2400_data },
{ .compatible = "aspeed,ast2500-scu", .data = &ast2500_data },
{ }
};
static struct platform_driver aspeed_clk_driver = {
.probe = aspeed_clk_probe,
.driver = {
.name = "aspeed-clk",
.of_match_table = aspeed_clk_dt_ids,
.suppress_bind_attrs = true,
},
};
builtin_platform_driver(aspeed_clk_driver);
static void __init aspeed_ast2400_cc(struct regmap *map)
{
struct clk_hw *hw;
u32 val, div, clkin, hpll;
const u16 hpll_rates[][4] = {
{384, 360, 336, 408},
{400, 375, 350, 425},
};
int rate;
/*
* CLKIN is the crystal oscillator, 24, 48 or 25MHz selected by
* strapping
*/
regmap_read(map, ASPEED_STRAP, &val);
rate = (val >> 8) & 3;
if (val & CLKIN_25MHZ_EN) {
clkin = 25000000;
hpll = hpll_rates[1][rate];
} else if (val & AST2400_CLK_SOURCE_SEL) {
clkin = 48000000;
hpll = hpll_rates[0][rate];
} else {
clkin = 24000000;
hpll = hpll_rates[0][rate];
}
hw = clk_hw_register_fixed_rate(NULL, "clkin", NULL, 0, clkin);
pr_debug("clkin @%u MHz\n", clkin / 1000000);
/*
* High-speed PLL clock derived from the crystal. This the CPU clock,
* and we assume that it is enabled. It can be configured through the
* HPLL_PARAM register, or set to a specified frequency by strapping.
*/
regmap_read(map, ASPEED_HPLL_PARAM, &val);
if (val & AST2400_HPLL_PROGRAMMED)
hw = aspeed_ast2400_calc_pll("hpll", val);
else
hw = clk_hw_register_fixed_rate(NULL, "hpll", "clkin", 0,
hpll * 1000000);
aspeed_clk_data->hws[ASPEED_CLK_HPLL] = hw;
/*
* Strap bits 11:10 define the CPU/AHB clock frequency ratio (aka HCLK)
* 00: Select CPU:AHB = 1:1
* 01: Select CPU:AHB = 2:1
* 10: Select CPU:AHB = 4:1
* 11: Select CPU:AHB = 3:1
*/
regmap_read(map, ASPEED_STRAP, &val);
val = (val >> 10) & 0x3;
div = val + 1;
if (div == 3)
div = 4;
else if (div == 4)
div = 3;
hw = clk_hw_register_fixed_factor(NULL, "ahb", "hpll", 0, 1, div);
aspeed_clk_data->hws[ASPEED_CLK_AHB] = hw;
/* APB clock clock selection register SCU08 (aka PCLK) */
hw = clk_hw_register_divider_table(NULL, "apb", "hpll", 0,
scu_base + ASPEED_CLK_SELECTION, 23, 3, 0,
ast2400_div_table,
&aspeed_clk_lock);
aspeed_clk_data->hws[ASPEED_CLK_APB] = hw;
}
static void __init aspeed_ast2500_cc(struct regmap *map)
{
struct clk_hw *hw;
u32 val, freq, div;
/* CLKIN is the crystal oscillator, 24 or 25MHz selected by strapping */
regmap_read(map, ASPEED_STRAP, &val);
if (val & CLKIN_25MHZ_EN)
freq = 25000000;
else
freq = 24000000;
hw = clk_hw_register_fixed_rate(NULL, "clkin", NULL, 0, freq);
pr_debug("clkin @%u MHz\n", freq / 1000000);
/*
* High-speed PLL clock derived from the crystal. This the CPU clock,
* and we assume that it is enabled
*/
regmap_read(map, ASPEED_HPLL_PARAM, &val);
aspeed_clk_data->hws[ASPEED_CLK_HPLL] = aspeed_ast2500_calc_pll("hpll", val);
/* Strap bits 11:9 define the AXI/AHB clock frequency ratio (aka HCLK)*/
regmap_read(map, ASPEED_STRAP, &val);
val = (val >> 9) & 0x7;
WARN(val == 0, "strapping is zero: cannot determine ahb clock");
div = 2 * (val + 1);
hw = clk_hw_register_fixed_factor(NULL, "ahb", "hpll", 0, 1, div);
aspeed_clk_data->hws[ASPEED_CLK_AHB] = hw;
/* APB clock clock selection register SCU08 (aka PCLK) */
regmap_read(map, ASPEED_CLK_SELECTION, &val);
val = (val >> 23) & 0x7;
div = 4 * (val + 1);
hw = clk_hw_register_fixed_factor(NULL, "apb", "hpll", 0, 1, div);
aspeed_clk_data->hws[ASPEED_CLK_APB] = hw;
};
static void __init aspeed_cc_init(struct device_node *np)
{
struct regmap *map;
u32 val;
int ret;
int i;
scu_base = of_iomap(np, 0);
if (!scu_base)
return;
aspeed_clk_data = kzalloc(struct_size(aspeed_clk_data, hws,
ASPEED_NUM_CLKS),
GFP_KERNEL);
if (!aspeed_clk_data)
return;
/*
* This way all clocks fetched before the platform device probes,
* except those we assign here for early use, will be deferred.
*/
for (i = 0; i < ASPEED_NUM_CLKS; i++)
aspeed_clk_data->hws[i] = ERR_PTR(-EPROBE_DEFER);
map = syscon_node_to_regmap(np);
if (IS_ERR(map)) {
pr_err("no syscon regmap\n");
return;
}
/*
* We check that the regmap works on this very first access,
* but as this is an MMIO-backed regmap, subsequent regmap
* access is not going to fail and we skip error checks from
* this point.
*/
ret = regmap_read(map, ASPEED_STRAP, &val);
if (ret) {
pr_err("failed to read strapping register\n");
return;
}
if (of_device_is_compatible(np, "aspeed,ast2400-scu"))
aspeed_ast2400_cc(map);
else if (of_device_is_compatible(np, "aspeed,ast2500-scu"))
aspeed_ast2500_cc(map);
else
pr_err("unknown platform, failed to add clocks\n");
aspeed_clk_data->num = ASPEED_NUM_CLKS;
ret = of_clk_add_hw_provider(np, of_clk_hw_onecell_get, aspeed_clk_data);
if (ret)
pr_err("failed to add DT provider: %d\n", ret);
};
CLK_OF_DECLARE_DRIVER(aspeed_cc_g5, "aspeed,ast2500-scu", aspeed_cc_init);
CLK_OF_DECLARE_DRIVER(aspeed_cc_g4, "aspeed,ast2400-scu", aspeed_cc_init);
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