2023-05-16 07:43:43

by Claudiu Beznea

[permalink] [raw]
Subject: [PATCH v2] memory: atmel-sdramc: remove the driver

Driver does only clock request + enable for DDR clocks. DDR clocks are
enabled by bootloader and need to stay that way in Linux. To avoid having
these clocks disabled by clock subsystem in case there are no Linux
consumers for them the clocks were marked as critical in clock drivers
(in commit 68b3b6f1773d ("clk: at91: mark ddr clocks as critical")).
With this, there is no need to have a separate driver that only does
clock request + enable.

Signed-off-by: Claudiu Beznea <[email protected]>
---

Changes in v2:
- remove ATMEL_SDRAMC references in Kconfigs
- the patch was initially part of this series:
https://lore.kernel.org/all/[email protected]/

arch/arm/mach-at91/Kconfig | 4 --
drivers/memory/Kconfig | 11 ------
drivers/memory/Makefile | 1 -
drivers/memory/atmel-sdramc.c | 74 -----------------------------------
4 files changed, 90 deletions(-)
delete mode 100644 drivers/memory/atmel-sdramc.c

diff --git a/arch/arm/mach-at91/Kconfig b/arch/arm/mach-at91/Kconfig
index 3dd9e718661b..a8c022b4c053 100644
--- a/arch/arm/mach-at91/Kconfig
+++ b/arch/arm/mach-at91/Kconfig
@@ -97,7 +97,6 @@ config SOC_AT91SAM9
depends on ARCH_MULTI_V5
select ATMEL_AIC_IRQ
select ATMEL_PM if PM
- select ATMEL_SDRAMC
select CPU_ARM926T
select HAVE_AT91_SMD
select HAVE_AT91_USB_CLK
@@ -131,7 +130,6 @@ config SOC_SAM9X60
depends on ARCH_MULTI_V5
select ATMEL_AIC5_IRQ
select ATMEL_PM if PM
- select ATMEL_SDRAMC
select CPU_ARM926T
select HAVE_AT91_USB_CLK
select HAVE_AT91_GENERATED_CLK
@@ -213,7 +211,6 @@ config SOC_SAMA5
bool
select ATMEL_AIC5_IRQ
select ATMEL_PM if PM
- select ATMEL_SDRAMC
select MEMORY
select SOC_SAM_V7
select SRAM if PM
@@ -234,7 +231,6 @@ config SOC_SAMA7
bool
select ARM_GIC
select ATMEL_PM if PM
- select ATMEL_SDRAMC
select MEMORY
select SOC_SAM_V7
select SRAM if PM
diff --git a/drivers/memory/Kconfig b/drivers/memory/Kconfig
index 91774e6ee624..8efdd1f97139 100644
--- a/drivers/memory/Kconfig
+++ b/drivers/memory/Kconfig
@@ -30,17 +30,6 @@ config ARM_PL172_MPMC
If you have an embedded system with an AMBA bus and a PL172
controller, say Y or M here.

-config ATMEL_SDRAMC
- bool "Atmel (Multi-port DDR-)SDRAM Controller"
- default y if ARCH_AT91
- depends on ARCH_AT91 || COMPILE_TEST
- depends on OF
- help
- This driver is for Atmel SDRAM Controller or Atmel Multi-port
- DDR-SDRAM Controller available on Atmel AT91SAM9 and SAMA5 SoCs.
- Starting with the at91sam9g45, this controller supports SDR, DDR and
- LP-DDR memories.
-
config ATMEL_EBI
bool "Atmel EBI driver"
default y if ARCH_AT91
diff --git a/drivers/memory/Makefile b/drivers/memory/Makefile
index ae14ded464a8..d2e6ca9abbe0 100644
--- a/drivers/memory/Makefile
+++ b/drivers/memory/Makefile
@@ -8,7 +8,6 @@ ifeq ($(CONFIG_DDR),y)
obj-$(CONFIG_OF) += of_memory.o
endif
obj-$(CONFIG_ARM_PL172_MPMC) += pl172.o
-obj-$(CONFIG_ATMEL_SDRAMC) += atmel-sdramc.o
obj-$(CONFIG_ATMEL_EBI) += atmel-ebi.o
obj-$(CONFIG_BRCMSTB_DPFE) += brcmstb_dpfe.o
obj-$(CONFIG_BRCMSTB_MEMC) += brcmstb_memc.o
diff --git a/drivers/memory/atmel-sdramc.c b/drivers/memory/atmel-sdramc.c
deleted file mode 100644
index ea6e9e1eaf04..000000000000
--- a/drivers/memory/atmel-sdramc.c
+++ /dev/null
@@ -1,74 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-only
-/*
- * Atmel (Multi-port DDR-)SDRAM Controller driver
- *
- * Author: Alexandre Belloni <[email protected]>
- *
- * Copyright (C) 2014 Atmel
- */
-
-#include <linux/clk.h>
-#include <linux/err.h>
-#include <linux/kernel.h>
-#include <linux/init.h>
-#include <linux/of_platform.h>
-#include <linux/platform_device.h>
-
-struct at91_ramc_caps {
- bool has_ddrck;
- bool has_mpddr_clk;
-};
-
-static const struct at91_ramc_caps at91rm9200_caps = { };
-
-static const struct at91_ramc_caps at91sam9g45_caps = {
- .has_ddrck = 1,
- .has_mpddr_clk = 0,
-};
-
-static const struct at91_ramc_caps sama5d3_caps = {
- .has_ddrck = 1,
- .has_mpddr_clk = 1,
-};
-
-static const struct of_device_id atmel_ramc_of_match[] = {
- { .compatible = "atmel,at91rm9200-sdramc", .data = &at91rm9200_caps, },
- { .compatible = "atmel,at91sam9260-sdramc", .data = &at91rm9200_caps, },
- { .compatible = "atmel,at91sam9g45-ddramc", .data = &at91sam9g45_caps, },
- { .compatible = "atmel,sama5d3-ddramc", .data = &sama5d3_caps, },
- {},
-};
-
-static int atmel_ramc_probe(struct platform_device *pdev)
-{
- const struct at91_ramc_caps *caps;
- struct clk *clk;
-
- caps = of_device_get_match_data(&pdev->dev);
-
- if (caps->has_ddrck) {
- clk = devm_clk_get_enabled(&pdev->dev, "ddrck");
- if (IS_ERR(clk))
- return PTR_ERR(clk);
- }
-
- if (caps->has_mpddr_clk) {
- clk = devm_clk_get_enabled(&pdev->dev, "mpddr");
- if (IS_ERR(clk)) {
- pr_err("AT91 RAMC: couldn't get mpddr clock\n");
- return PTR_ERR(clk);
- }
- }
-
- return 0;
-}
-
-static struct platform_driver atmel_ramc_driver = {
- .probe = atmel_ramc_probe,
- .driver = {
- .name = "atmel-ramc",
- .of_match_table = atmel_ramc_of_match,
- },
-};
-
-builtin_platform_driver(atmel_ramc_driver);
--
2.34.1



2023-06-02 08:53:47

by Krzysztof Kozlowski

[permalink] [raw]
Subject: Re: [PATCH v2] memory: atmel-sdramc: remove the driver


On Tue, 16 May 2023 10:24:05 +0300, Claudiu Beznea wrote:
> Driver does only clock request + enable for DDR clocks. DDR clocks are
> enabled by bootloader and need to stay that way in Linux. To avoid having
> these clocks disabled by clock subsystem in case there are no Linux
> consumers for them the clocks were marked as critical in clock drivers
> (in commit 68b3b6f1773d ("clk: at91: mark ddr clocks as critical")).
> With this, there is no need to have a separate driver that only does
> clock request + enable.
>
> [...]

Applied, thanks!

[1/1] memory: atmel-sdramc: remove the driver
https://git.kernel.org/krzk/linux-mem-ctrl/c/d3369a4b6f0164b8869a097547846ed4e5c9c47f

Best regards,
--
Krzysztof Kozlowski <[email protected]>