Commit Graph

6 Commits

Author SHA1 Message Date
Ivaylo Ivanov
dd303e0219 soc: samsung: usi: prevent wrong bits inversion during unconfiguring
Instead of setting bit 1 (USI_OPTION_CLKSTOP_ON) during USI unconfiguring,
all the other bits in the USI_OPTION register get inverted, which
should not happen as that means the clock will keep getting provided
to the USI IP. Remove the unnecessary tilde.

Fixes: 11e77776b5 ("soc: samsung: usi: add a routine for unconfiguring the ip")
Signed-off-by: Ivaylo Ivanov <ivo.ivanov.ivanov1@gmail.com>
Link: https://lore.kernel.org/r/20250413163755.788907-1-ivo.ivanov.ivanov1@gmail.com
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
2025-04-14 08:51:18 +02:00
Arnd Bergmann
4c57930f68 soc: samsung: include linux/array_size.h where needed
This does not necessarily get included through asm/io.h:

drivers/soc/samsung/exynos3250-pmu.c:120:18: error: use of undeclared identifier 'ARRAY_SIZE'
  120 |         for (i = 0; i < ARRAY_SIZE(exynos3250_list_feed); i++) {
      |                         ^
drivers/soc/samsung/exynos5250-pmu.c:162:18: error: use of undeclared identifier 'ARRAY_SIZE'
  162 |         for (i = 0; i < ARRAY_SIZE(exynos5_list_both_cnt_feed); i++) {
      |                         ^

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20250305211446.43772-1-arnd@kernel.org
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
2025-03-06 19:10:17 +01:00
Ivaylo Ivanov
b88cd5c854 soc: samsung: usi: implement support for USIv1 and exynos8895
USIv1 IP-core is found on some ARM64 Exynos SoCs (like Exynos8895) and
provides selectable serial protocols (one of: HSI2C0, HSI2C1, HSI2C0_1,
SPI, UART, UART_HSI2C1).

USIv1, unlike USIv2, doesn't have any known register map. Underlying
protocols that it implements have no offset, like with Exynos850.
Desired protocol can be chosen via SW_CONF register from System
Register block of the same domain as USI.

In order to select a particular protocol, the protocol has to be
selected via the System Register. Unlike USIv2, there's no need for
any setup before the given protocol becomes accessible apart from
enabling the APB clock and the protocol operating clock.

Modify the existing driver in order to allow USIv1 instances in
Exynos8895 to probe and set their protocol. While we're at it,
make use of the new mode constants in place of the old ones.

Signed-off-by: Ivaylo Ivanov <ivo.ivanov.ivanov1@gmail.com>
Link: https://lore.kernel.org/r/20250204172803.3425496-4-ivo.ivanov.ivanov1@gmail.com
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
2025-02-05 16:27:34 +01:00
Ivaylo Ivanov
11e77776b5 soc: samsung: usi: add a routine for unconfiguring the ip
Add a devm_add_action_or_reset() routine for unconfiguring the USI IP
block whenever the device gets removed.

Signed-off-by: Ivaylo Ivanov <ivo.ivanov.ivanov1@gmail.com>
Link: https://lore.kernel.org/r/20250204172803.3425496-3-ivo.ivanov.ivanov1@gmail.com
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
2025-02-05 16:25:57 +01:00
Krzysztof Kozlowski
00c1fda73d soc: samsung: Use syscon_regmap_lookup_by_phandle_args
Use syscon_regmap_lookup_by_phandle_args() which is a wrapper over
syscon_regmap_lookup_by_phandle() combined with getting the syscon
argument.  Except simpler code this annotates within one line that given
phandle has arguments, so grepping for code would be easier.

Link: https://lore.kernel.org/r/20250111185402.183793-1-krzysztof.kozlowski@linaro.org
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
2025-02-03 12:56:34 +01:00
Sam Protsenko
b603377e40 soc: samsung: Add USI driver
USIv2 IP-core is found on modern ARM64 Exynos SoCs (like Exynos850) and
provides selectable serial protocol (one of: UART, SPI, I2C). USIv2
registers usually reside in the same register map as a particular
underlying protocol it implements, but have some particular offset. E.g.
on Exynos850 the USI_UART has 0x13820000 base address, where UART
registers have 0x00..0x40 offsets, and USI registers have 0xc0..0xdc
offsets. Desired protocol can be chosen via SW_CONF register from System
Register block of the same domain as USI.

Before starting to use a particular protocol, USIv2 must be configured
properly:
  1. Select protocol to be used via System Register
  2. Clear "reset" flag in USI_CON
  3. Configure HWACG behavior (e.g. for UART Rx the HWACG must be
     disabled, so that the IP clock is not gated automatically); this is
     done using USI_OPTION register
  4. Keep both USI clocks (PCLK and IPCLK) running during USI registers
     modification

This driver implements the above behavior. Of course, USIv2 driver
should be probed before UART/I2C/SPI drivers. It can be achieved by
embedding UART/I2C/SPI nodes inside of the USI node (in Device Tree);
driver then walks underlying nodes and instantiates those. Driver also
handles USI configuration on PM resume, as register contents can be lost
during CPU suspend.

This driver is designed with different USI versions in mind. So it
should be relatively easy to add new USI revisions to it later.

Signed-off-by: Sam Protsenko <semen.protsenko@linaro.org>
Link: https://lore.kernel.org/r/20211204195757.8600-3-semen.protsenko@linaro.org
Tested-by: Chanho Park <chanho61.park@samsung.com>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
2021-12-18 11:55:56 +01:00