BMC/Intel-BMC/linux.git/drivers/clk/clk.c, branch dev-5.2

clk: Fix potential NULL dereference in clk_fetch_parent_index()

2019-09-10T09:35:17+00:00

[ Upstream commit 24876f09a7dfe36a82f53d304d8c1bceb3257a0f ] Don't compare the parent clock name with a NULL name in the clk_parent_map. This prevents a kernel crash when passing NULL core->parents[i].name to strcmp(). An example which triggered this is a mux clock with four parents when each of them is referenced in the clock driver using clk_parent_data.fw_name and then calling clk_set_parent(clk, 3rd_parent) on this mux. In this case the first parent is also the HW default so core->parents[i].hw is populated when the clock is registered. Calling clk_set_parent(clk, 3rd_parent) will then go through all parents and skip the first parent because it's hw pointer doesn't match. For the second parent no hw pointer is cached yet and clk_core_get(core, 1) returns a non-matching pointer (which is correct because we are comparing the second with the third parent). Comparing the result of clk_core_get(core, 2) with the requested parent gives a match. However we don't reach this point because right after the clk_core_get(core, 1) mismatch the old code tried to !strcmp(parent->name, NULL) (where the second argument is actually core->parents[i].name, but that was never populated by the clock driver). Signed-off-by: Martin Blumenstingl Link: https://lkml.kernel.org/r/20190815223155.21384-1-martin.blumenstingl@googlemail.com Fixes: fc0c209c147f ("clk: Allow parents to be specified without string names") Signed-off-by: Stephen Boyd Signed-off-by: Sasha Levin

clk: Fix falling back to legacy parent string matching

2019-09-10T09:35:17+00:00

[ Upstream commit 4f8c6aba37da199155a121c6cdc38505a9eb0259 ] Calls to clk_core_get() will return ERR_PTR(-EINVAL) if we've started migrating a clk driver to use the DT based style of specifying parents but we haven't made any DT updates yet. This happens when we pass a non-NULL value as the 'name' argument of of_parse_clkspec(). That function returns -EINVAL in such a situation, instead of -ENOENT like we expected. The return value comes back up to clk_core_fill_parent_index() which proceeds to skip calling clk_core_lookup() because the error pointer isn't equal to -ENOENT, it's -EINVAL. Furthermore, we blindly overwrite the error pointer returned by clk_core_get() with NULL when there isn't a legacy .name member specified in the parent map. This isn't too bad right now because we don't really care to differentiate NULL from an error, but in the future we should only try to do a legacy lookup if we know we might find something. This way DT lookups that fail don't try to lookup based on strings when there isn't any string to match, hiding the error from DT parsing. Fix both these problems so that clk provider drivers can use the new style of parent mapping without having to also update their DT at the same time. This patch is based on an earlier patch from Taniya Das which checked for -EINVAL in addition to -ENOENT return values from clk_core_get(). Fixes: 601b6e93304a ("clk: Allow parents to be specified via clkspec index") Cc: Taniya Das Cc: Jerome Brunet Cc: Chen-Yu Tsai Reported-by: Taniya Das Signed-off-by: Stephen Boyd Link: https://lkml.kernel.org/r/20190813214147.34394-1-sboyd@kernel.org Tested-by: Taniya Das Signed-off-by: Sasha Levin

clk: Do a DT parent lookup even when index < 0

2019-06-17T14:13:54+00:00

We want to allow the parent lookup to happen even if the index is some value less than 0. This may be the case if a clk provider only specifies the .name member to match a string in the "clock-names" DT property. We shouldn't require that the index be >= 0 to make this use case work. Fixes: 601b6e93304a ("clk: Allow parents to be specified via clkspec index") Reported-by: Alexandre Mergnat Cc: Jerome Brunet Cc: Chen-Yu Tsai Reviewed-by: Chen-Yu Tsai Signed-off-by: Stephen Boyd

Merge branch 'clk-parent-rewrite-1' into clk-next

2019-05-07T18:46:13+00:00

- Rewrite how clk parents can be specified to be DT/clkdev based instead of just string based * clk-parent-rewrite-1: clk: Cache core in clk_fetch_parent_index() without names clk: fixed-factor: Initialize clk_init_data on stack clk: fixed-factor: Let clk framework find parent clk: Allow parents to be specified via clkspec index clk: Look for parents with clkdev based clk_lookups clk: Allow parents to be specified without string names clk: Add of_clk_hw_register() API for early clk drivers driver core: Let dev_of_node() accept a NULL dev clk: Prepare for clk registration API that uses DT nodes clkdev: Move clk creation outside of 'clocks_mutex'

Merge branch 'clk-ti' into clk-next

2019-05-07T18:46:02+00:00

* clk-ti: clk: Remove CLK_IS_BASIC clk flag clk: ti: dra7: disable the RNG and TIMER12 clkctrl clocks on HS devices clk: ti: dra7x: prevent non-existing clkctrl clocks from registering ARM: omap2+: hwmod: drop CLK_IS_BASIC flag usage clk: ti: export the omap2_clk_is_hw_omap call

Merge branches 'clk-doc', 'clk-more-critical', 'clk-meson' and 'clk-basic-be' into clk-next

2019-05-07T18:44:42+00:00

- Remove clk_readl() and introduce BE versions of basic clk types * clk-doc: clk: Drop duplicate clk_register() documentation clk: Document and simplify clk_core_get_rate_nolock() clk: Remove 'flags' member of struct clk_fixed_rate clk: nxp: Drop 'flags' on fixed_rate clk macro clk: Document __clk_mux_determine_rate() clk: Document CLK_MUX_READ_ONLY mux flag clk: Document deprecated things clk: Collapse gpio clk kerneldoc * clk-more-critical: clk: highbank: Convert to CLK_IS_CRITICAL * clk-meson: (21 commits) clk: meson: axg-audio: add g12a support clk: meson: axg-audio: don't register inputs in the onecell data clk: meson: axg_audio: replace prefix axg by aud dt-bindings: clk: axg-audio: add g12a support clk: meson: meson8b: add the video decoder clock trees clk: meson: meson8b: add the VPU clock trees clk: meson: meson8b: add support for the GP_PLL clock on Meson8m2 clk: meson: meson8b: use a separate clock table for Meson8m2 dt-bindings: clock: meson8b: export the video decoder clocks clk: meson-g12a: add video decoder clocks dt-bindings: clock: meson8b: export the VPU clock clk: meson-g12a: add PCIE PLL clocks dt-bindings: clock: g12a-aoclk: expose CLKID_AO_CTS_OSCIN clk: meson-pll: add reduced specific clk_ops for G12A PCIe PLL dt-bindings: clock: meson8b: drop the "ABP" clock definition clk: meson: g12a: add cpu clocks dt-bindings: clk: g12a-clkc: add VDEC clock IDs dt-bindings: clock: axg-audio: unexpose controller inputs dt-bindings: clk: g12a-clkc: add PCIE PLL clock ID clk: g12a-aoclk: re-export CLKID_AO_SAR_ADC_SEL clock id ... * clk-basic-be: clk: core: replace clk_{readl,writel} with {readl,writel} clk: core: remove powerpc special handling powerpc/512x: mark clocks as big endian clk: mux: add explicit big endian support clk: multiplier: add explicit big endian support clk: gate: add explicit big endian support clk: fractional-divider: add explicit big endian support clk: divider: add explicit big endian support

clk: Cache core in clk_fetch_parent_index() without names

2019-05-03T17:38:01+00:00

If a clk has specified parents via clk_hw pointers it won't specify the globally unique names for the parents. Without the unique names, we can't fallback to comparing them against the name of the 'parent' pointer here. Therefore, do a pointer comparison against the clk_hw pointers too and cache the clk_core structure if they match. This fixes parent lookup code for clks that only specify clk_hw pointers and nothing else, like muxes that are purely inside a clk controller. Similarly, if the parent pointer isn't cached after trying to match clk_core or clk_hw pointers, lookup the pointer from DT or via clkdev lookups instead of relying purely on the globally unique clk name match. This should allow us to move away from having to specify global names for clk parents entirely. While we're in the area, add some comments so it's clearer what's going on. The if statements don't lend themselves to much clarity in their raw form. Fixes: fc0c209c147f ("clk: Allow parents to be specified without string names") Reported-by: Charles Keepax Signed-off-by: Stephen Boyd

clk: Remove CLK_IS_BASIC clk flag

2019-04-26T17:40:49+00:00

This flag was historically used to indicate that a clk is a "basic" type of clk like a mux, divider, gate, etc. This never turned out to be very useful though because it was hard to cleanly split "basic" clks from other clks in a system. This one flag was a way for type introspection and it just didn't scale. If anything, it was used by the TI clk driver to indicate that a clk_hw wasn't contained in the SoC specific clk structure. We can get rid of this define now that TI is finding those clks a different way. Cc: Tero Kristo Cc: Ralf Baechle Cc: Paul Burton Cc: James Hogan Cc: Cc: Thierry Reding Cc: Kevin Hilman Cc: Cc: Acked-by: Thierry Reding Signed-off-by: Stephen Boyd

clk: Allow parents to be specified via clkspec index

2019-04-19T21:53:19+00:00

Some clk providers are simple DT nodes that only have a 'clocks' property without having an associated 'clock-names' property. In these cases, we want to let these clk providers point to their parent clks without having to dereference the 'clocks' property at probe time to figure out the parent's globally unique clk name. Let's add an 'index' property to the parent_data structure so that clk providers can indicate that their parent is a particular index in the 'clocks' DT property. Cc: Miquel Raynal Cc: Jerome Brunet Cc: Russell King Cc: Michael Turquette Cc: Jeffrey Hugo Cc: Chen-Yu Tsai Tested-by: Jeffrey Hugo Signed-off-by: Stephen Boyd

clk: Look for parents with clkdev based clk_lookups

2019-04-19T21:53:00+00:00

In addition to looking for DT based parents, support clkdev based clk_lookups. This should allow non-DT based clk drivers to participate in the parent lookup process. Cc: Miquel Raynal Cc: Jerome Brunet Cc: Russell King Cc: Michael Turquette Cc: Jeffrey Hugo Cc: Chen-Yu Tsai Tested-by: Jeffrey Hugo Signed-off-by: Stephen Boyd