[ Upstream commit 0370395d45 ]
Probing peripherals in the AON and PERI domains, such as the PVT thermal
sensor and the PWM controller, can lead to boot hangs or unresponsive
devices on the LPi4A board. The root cause is that their parent bus
clocks ('CLK_CPU2AON_X2H' and the 'CLK_PERISYS_APB' clocks) are
automatically gated by the kernel's power-saving mechanisms when the bus
is perceived as idle.
Alternative solutions were investigated, including modeling the parent
bus in the Device Tree with 'simple-pm-bus' or refactoring the clock
driver's parentage. The 'simple-pm-bus' approach is not viable due to
the lack of defined bus address ranges in the hardware manual and its
creation of improper dependencies on the 'pm_runtime' API for consumer
drivers.
Therefore, applying the'`CLK_IGNORE_UNUSED' flag directly to the
essential bus clocks is the most direct and targeted fix. This prevents
the kernel from auto-gating these buses and ensures peripherals remain
accessible.
This change fixes the boot hang associated with the PVT sensor and
resolves the functional issues with the PWM controller.
Link: https://lore.kernel.org/all/9e8a12db-236d-474c-b110-b3be96edf057@samsung.com/ [1]
Reviewed-by: Drew Fustini <drew@pdp7.com>
Acked-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Michal Wilczynski <m.wilczynski@samsung.com>
Signed-off-by: Drew Fustini <drew@pdp7.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit d274c77ffa ]
The "osc_12m" fixed factor clock refers the external oscillator by
setting clk_parent_data.fw_name to osc_24m, which is obviously wrong
since no clock-names property is allowed for compatible
thead,th1520-clk-ap.
Refer the oscillator as parent by index instead.
Fixes: ae81b69fd2 ("clk: thead: Add support for T-Head TH1520 AP_SUBSYS clocks")
Signed-off-by: Yao Zi <ziyao@disroot.org>
Reviewed-by: Drew Fustini <fustini@kernel.org>
Signed-off-by: Drew Fustini <fustini@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 3a43cd19f1 ]
cpu2vp_clk is a gate but was mistakenly in th1520_div_clks[] instead
of th1520_gate_clks[].
Fixes: ae81b69fd2 ("clk: thead: Add support for T-Head TH1520 AP_SUBSYS clocks")
Signed-off-by: Drew Fustini <dfustini@tenstorrent.com>
Link: https://lore.kernel.org/r/20241228034802.1573554-1-dfustini@tenstorrent.com
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 037705e94b ]
Add the CLK_IGNORE_UNUSED flag to apb_pclk, cpu2peri_x2h_clk,
perisys_apb2_hclk and perisys_apb3_hclk.
Without this flag, the boot hangs after "clk: Disabling unused clocks"
unless clk_ignore_unused is in the kernel cmdline.
Fixes: ae81b69fd2 ("clk: thead: Add support for T-Head TH1520 AP_SUBSYS clocks")
Signed-off-by: Drew Fustini <dfustini@tenstorrent.com>
Link: https://lore.kernel.org/r/20250113-th1520-clk_ignore_unused-v1-2-0b08fb813438@tenstorrent.com
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit a826e53fd7 ]
Modify the call to devm_clk_hw_register_gate_parent_data() to actually
pass the clk flags from hw.init instead of just 0. This is necessary to
allow individual clk gates to specify their own clk flags.
Fixes: ae81b69fd2 ("clk: thead: Add support for T-Head TH1520 AP_SUBSYS clocks")
Signed-off-by: Drew Fustini <dfustini@tenstorrent.com>
Link: https://lore.kernel.org/r/20250113-th1520-clk_ignore_unused-v1-1-0b08fb813438@tenstorrent.com
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit f4bf0b909a ]
In accordance with LicheePi 4A BSP the clock that comes to emmc/sdhci
is 198Mhz which is got through frequency division of source clock
VIDEO PLL by 4 [1].
But now the AP_SUBSYS driver sets the CLK EMMC SDIO to the same
frequency as the VIDEO PLL, equal to 792 MHz. This causes emmc/sdhci
to work 4 times slower.
Let's fix this issue by adding fixed factor clock that divides
VIDEO PLL by 4 for emmc/sdhci.
Link: 7563179071/drivers/clk/thead/clk-light-fm.c (L454)
Fixes: ae81b69fd2 ("clk: thead: Add support for T-Head TH1520 AP_SUBSYS clocks")
Signed-off-by: Maksim Kiselev <bigunclemax@gmail.com>
Link: https://lore.kernel.org/r/20241210083029.92620-1-bigunclemax@gmail.com
Tested-by: Xi Ruoyao <xry111@xry111.site>
Reviewed-by: Drew Fustini <dfustini@tenstorrent.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Add the CLK_IGNORE_UNUSED flag to the vp-axi clock (CLK_VP_AXI) to avoid
depending on clk_ignore_unused in the cmdline. Without this fix, the
emmc-sdio clock (CLK_EMMC_SDIO) fails to work after vp-axi is disabled.
Signed-off-by: Drew Fustini <drew@pdp7.com>
Link: https://lore.kernel.org/r/20240731061439.3807172-1-drew@pdp7.com
Fixes: ae81b69fd2 ("clk: thead: Add support for T-Head TH1520 AP_SUBSYS clocks")
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
This fails to build on 32-bit targets because of a missing __udivdi3.
IIRC the right way to fix that is to avoid the division, but I just want
a tree that builds and the only real T-Head platforms are 64-bit right
now.
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Link: https://lore.kernel.org/r/20240719151027.16152-1-palmer@rivosinc.com
Acked-by: Drew Fustini <drew@pdp7.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
