linux/drivers/clk/at91/at91sam9n12.c
Ahmad Fatoum 153bc1c66a clk: at91: fix possible dead lock in new drivers
syscon_node_to_regmap() will make the created regmap get and enable the
first clock it can parse from the device tree. This clock is not needed to
access the registers and should not be enabled at that time.

Use device_node_to_regmap to resolve this as it looks up the regmap in
the same list but doesn't care about the clocks. This issue is detected
by lockdep when booting the sama5d3 with a device tree containing the
new clk bindings.

This fix already happened in 6956eb33ab ("clk: at91: fix possible
deadlock") for the drivers that had been migrated to the new clk binding
back then. This does the same for the new drivers as well.

Fixes: 01e2113de9 ("clk: at91: add sam9x60 pmc driver")
Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Link: https://lore.kernel.org/r/20200703073236.23923-1-a.fatoum@pengutronix.de
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2020-07-24 02:18:42 -07:00

245 lines
6.3 KiB
C

// SPDX-License-Identifier: GPL-2.0
#include <linux/clk-provider.h>
#include <linux/mfd/syscon.h>
#include <linux/slab.h>
#include <dt-bindings/clock/at91.h>
#include "pmc.h"
static const struct clk_master_characteristics mck_characteristics = {
.output = { .min = 0, .max = 133333333 },
.divisors = { 1, 2, 4, 3 },
.have_div3_pres = 1,
};
static u8 plla_out[] = { 0, 1, 2, 3, 0, 1, 2, 3 };
static u16 plla_icpll[] = { 0, 0, 0, 0, 1, 1, 1, 1 };
static const struct clk_range plla_outputs[] = {
{ .min = 745000000, .max = 800000000 },
{ .min = 695000000, .max = 750000000 },
{ .min = 645000000, .max = 700000000 },
{ .min = 595000000, .max = 650000000 },
{ .min = 545000000, .max = 600000000 },
{ .min = 495000000, .max = 555000000 },
{ .min = 445000000, .max = 500000000 },
{ .min = 400000000, .max = 450000000 },
};
static const struct clk_pll_characteristics plla_characteristics = {
.input = { .min = 2000000, .max = 32000000 },
.num_output = ARRAY_SIZE(plla_outputs),
.output = plla_outputs,
.icpll = plla_icpll,
.out = plla_out,
};
static u8 pllb_out[] = { 0 };
static const struct clk_range pllb_outputs[] = {
{ .min = 30000000, .max = 100000000 },
};
static const struct clk_pll_characteristics pllb_characteristics = {
.input = { .min = 2000000, .max = 32000000 },
.num_output = ARRAY_SIZE(pllb_outputs),
.output = pllb_outputs,
.out = pllb_out,
};
static const struct {
char *n;
char *p;
u8 id;
} at91sam9n12_systemck[] = {
{ .n = "ddrck", .p = "masterck", .id = 2 },
{ .n = "lcdck", .p = "masterck", .id = 3 },
{ .n = "uhpck", .p = "usbck", .id = 6 },
{ .n = "udpck", .p = "usbck", .id = 7 },
{ .n = "pck0", .p = "prog0", .id = 8 },
{ .n = "pck1", .p = "prog1", .id = 9 },
};
static const struct clk_pcr_layout at91sam9n12_pcr_layout = {
.offset = 0x10c,
.cmd = BIT(12),
.pid_mask = GENMASK(5, 0),
.div_mask = GENMASK(17, 16),
};
struct pck {
char *n;
u8 id;
};
static const struct pck at91sam9n12_periphck[] = {
{ .n = "pioAB_clk", .id = 2, },
{ .n = "pioCD_clk", .id = 3, },
{ .n = "fuse_clk", .id = 4, },
{ .n = "usart0_clk", .id = 5, },
{ .n = "usart1_clk", .id = 6, },
{ .n = "usart2_clk", .id = 7, },
{ .n = "usart3_clk", .id = 8, },
{ .n = "twi0_clk", .id = 9, },
{ .n = "twi1_clk", .id = 10, },
{ .n = "mci0_clk", .id = 12, },
{ .n = "spi0_clk", .id = 13, },
{ .n = "spi1_clk", .id = 14, },
{ .n = "uart0_clk", .id = 15, },
{ .n = "uart1_clk", .id = 16, },
{ .n = "tcb_clk", .id = 17, },
{ .n = "pwm_clk", .id = 18, },
{ .n = "adc_clk", .id = 19, },
{ .n = "dma0_clk", .id = 20, },
{ .n = "uhphs_clk", .id = 22, },
{ .n = "udphs_clk", .id = 23, },
{ .n = "lcdc_clk", .id = 25, },
{ .n = "sha_clk", .id = 27, },
{ .n = "ssc0_clk", .id = 28, },
{ .n = "aes_clk", .id = 29, },
{ .n = "trng_clk", .id = 30, },
};
static void __init at91sam9n12_pmc_setup(struct device_node *np)
{
struct clk_range range = CLK_RANGE(0, 0);
const char *slck_name, *mainxtal_name;
struct pmc_data *at91sam9n12_pmc;
const char *parent_names[6];
struct regmap *regmap;
struct clk_hw *hw;
int i;
bool bypass;
i = of_property_match_string(np, "clock-names", "slow_clk");
if (i < 0)
return;
slck_name = of_clk_get_parent_name(np, i);
i = of_property_match_string(np, "clock-names", "main_xtal");
if (i < 0)
return;
mainxtal_name = of_clk_get_parent_name(np, i);
regmap = device_node_to_regmap(np);
if (IS_ERR(regmap))
return;
at91sam9n12_pmc = pmc_data_allocate(PMC_PLLBCK + 1,
nck(at91sam9n12_systemck), 31, 0, 2);
if (!at91sam9n12_pmc)
return;
hw = at91_clk_register_main_rc_osc(regmap, "main_rc_osc", 12000000,
50000000);
if (IS_ERR(hw))
goto err_free;
bypass = of_property_read_bool(np, "atmel,osc-bypass");
hw = at91_clk_register_main_osc(regmap, "main_osc", mainxtal_name,
bypass);
if (IS_ERR(hw))
goto err_free;
parent_names[0] = "main_rc_osc";
parent_names[1] = "main_osc";
hw = at91_clk_register_sam9x5_main(regmap, "mainck", parent_names, 2);
if (IS_ERR(hw))
goto err_free;
at91sam9n12_pmc->chws[PMC_MAIN] = hw;
hw = at91_clk_register_pll(regmap, "pllack", "mainck", 0,
&at91rm9200_pll_layout, &plla_characteristics);
if (IS_ERR(hw))
goto err_free;
hw = at91_clk_register_plldiv(regmap, "plladivck", "pllack");
if (IS_ERR(hw))
goto err_free;
at91sam9n12_pmc->chws[PMC_PLLACK] = hw;
hw = at91_clk_register_pll(regmap, "pllbck", "mainck", 1,
&at91rm9200_pll_layout, &pllb_characteristics);
if (IS_ERR(hw))
goto err_free;
at91sam9n12_pmc->chws[PMC_PLLBCK] = hw;
parent_names[0] = slck_name;
parent_names[1] = "mainck";
parent_names[2] = "plladivck";
parent_names[3] = "pllbck";
hw = at91_clk_register_master(regmap, "masterck", 4, parent_names,
&at91sam9x5_master_layout,
&mck_characteristics);
if (IS_ERR(hw))
goto err_free;
at91sam9n12_pmc->chws[PMC_MCK] = hw;
hw = at91sam9n12_clk_register_usb(regmap, "usbck", "pllbck");
if (IS_ERR(hw))
goto err_free;
parent_names[0] = slck_name;
parent_names[1] = "mainck";
parent_names[2] = "plladivck";
parent_names[3] = "pllbck";
parent_names[4] = "masterck";
for (i = 0; i < 2; i++) {
char name[6];
snprintf(name, sizeof(name), "prog%d", i);
hw = at91_clk_register_programmable(regmap, name,
parent_names, 5, i,
&at91sam9x5_programmable_layout);
if (IS_ERR(hw))
goto err_free;
at91sam9n12_pmc->pchws[i] = hw;
}
for (i = 0; i < ARRAY_SIZE(at91sam9n12_systemck); i++) {
hw = at91_clk_register_system(regmap, at91sam9n12_systemck[i].n,
at91sam9n12_systemck[i].p,
at91sam9n12_systemck[i].id);
if (IS_ERR(hw))
goto err_free;
at91sam9n12_pmc->shws[at91sam9n12_systemck[i].id] = hw;
}
for (i = 0; i < ARRAY_SIZE(at91sam9n12_periphck); i++) {
hw = at91_clk_register_sam9x5_peripheral(regmap, &pmc_pcr_lock,
&at91sam9n12_pcr_layout,
at91sam9n12_periphck[i].n,
"masterck",
at91sam9n12_periphck[i].id,
&range);
if (IS_ERR(hw))
goto err_free;
at91sam9n12_pmc->phws[at91sam9n12_periphck[i].id] = hw;
}
of_clk_add_hw_provider(np, of_clk_hw_pmc_get, at91sam9n12_pmc);
return;
err_free:
kfree(at91sam9n12_pmc);
}
/*
* The TCB is used as the clocksource so its clock is needed early. This means
* this can't be a platform driver.
*/
CLK_OF_DECLARE_DRIVER(at91sam9n12_pmc, "atmel,at91sam9n12-pmc",
at91sam9n12_pmc_setup);