From: Dario Binacchi dariobin@libero.it
[ Upstream commit 24b5b1978cd5a80db58e2a19db2f9c36fe8d4f7a ]
Enabling the framebuffer leads to a system hang. Running, as a debug hack, the store_pan() function in drivers/video/fbdev/core/fbsysfs.c without taking the console_lock, allows to see the crash backtrace on the serial line.
~ # echo 0 0 > /sys/class/graphics/fb0/pan
[ 9.719414] Unhandled exception: IPSR = 00000005 LR = fffffff1 [ 9.726937] CPU: 0 PID: 49 Comm: sh Not tainted 5.13.0-rc5 #9 [ 9.733008] Hardware name: STM32 (Device Tree Support) [ 9.738296] PC is at clk_gate_is_enabled+0x0/0x28 [ 9.743426] LR is at stm32f4_pll_div_set_rate+0xf/0x38 [ 9.748857] pc : [<0011e4be>] lr : [<0011f9e3>] psr: 0100000b [ 9.755373] sp : 00bc7be0 ip : 00000000 fp : 001f3ac4 [ 9.760812] r10: 002610d0 r9 : 01efe920 r8 : 00540560 [ 9.766269] r7 : 02e7ddb0 r6 : 0173eed8 r5 : 00000000 r4 : 004027c0 [ 9.773081] r3 : 0011e4bf r2 : 02e7ddb0 r1 : 0173eed8 r0 : 1d3267b8 [ 9.779911] xPSR: 0100000b [ 9.782719] CPU: 0 PID: 49 Comm: sh Not tainted 5.13.0-rc5 #9 [ 9.788791] Hardware name: STM32 (Device Tree Support) [ 9.794120] [<0000afa1>] (unwind_backtrace) from [<0000a33f>] (show_stack+0xb/0xc) [ 9.802421] [<0000a33f>] (show_stack) from [<0000a8df>] (__invalid_entry+0x4b/0x4c)
The `pll_num' field in the post_div_data configuration contained a wrong value which also referenced an uninitialized hardware clock when clk_register_pll_div() was called.
Fixes: 517633ef630e ("clk: stm32f4: Add post divisor for I2S & SAI PLLs") Signed-off-by: Dario Binacchi dariobin@libero.it Reviewed-by: Gabriel Fernandez gabriel.fernandez@st.com Link: https://lore.kernel.org/r/20210725160725.10788-1-dariobin@libero.it Signed-off-by: Stephen Boyd sboyd@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/clk/clk-stm32f4.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-)
diff --git a/drivers/clk/clk-stm32f4.c b/drivers/clk/clk-stm32f4.c index 96c6b6bc8f0e..46bc5f5d7134 100644 --- a/drivers/clk/clk-stm32f4.c +++ b/drivers/clk/clk-stm32f4.c @@ -453,7 +453,7 @@ struct stm32f4_pll {
struct stm32f4_pll_post_div_data { int idx; - u8 pll_num; + int pll_idx; const char *name; const char *parent; u8 flag; @@ -484,13 +484,13 @@ static const struct clk_div_table post_divr_table[] = {
#define MAX_POST_DIV 3 static const struct stm32f4_pll_post_div_data post_div_data[MAX_POST_DIV] = { - { CLK_I2SQ_PDIV, PLL_I2S, "plli2s-q-div", "plli2s-q", + { CLK_I2SQ_PDIV, PLL_VCO_I2S, "plli2s-q-div", "plli2s-q", CLK_SET_RATE_PARENT, STM32F4_RCC_DCKCFGR, 0, 5, 0, NULL},
- { CLK_SAIQ_PDIV, PLL_SAI, "pllsai-q-div", "pllsai-q", + { CLK_SAIQ_PDIV, PLL_VCO_SAI, "pllsai-q-div", "pllsai-q", CLK_SET_RATE_PARENT, STM32F4_RCC_DCKCFGR, 8, 5, 0, NULL },
- { NO_IDX, PLL_SAI, "pllsai-r-div", "pllsai-r", CLK_SET_RATE_PARENT, + { NO_IDX, PLL_VCO_SAI, "pllsai-r-div", "pllsai-r", CLK_SET_RATE_PARENT, STM32F4_RCC_DCKCFGR, 16, 2, 0, post_divr_table }, };
@@ -1489,7 +1489,7 @@ static void __init stm32f4_rcc_init(struct device_node *np) post_div->width, post_div->flag_div, post_div->div_table, - clks[post_div->pll_num], + clks[post_div->pll_idx], &stm32f4_clk_lock);
if (post_div->idx != NO_IDX)