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authorGabriel Somlo <gsomlo@gmail.com>2021-01-12 12:31:40 -0500
committerStafford Horne <shorne@gmail.com>2021-01-14 09:52:54 +0900
commit9d93a9e8aab3f82b6742dd034a6a81d4025cd82e (patch)
tree8846dbce998521fc20ad7212a5397dfef3dcc4f5 /drivers
parent131172a4a8ce3fccfd4a9f0f8b3c0d0e59222f1d (diff)
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drivers/soc/litex: move generic accessors to litex.h
Move generic LiteX CSR (MMIO) register accessors to litex.h and declare them as "static inline", in preparation for supporting 32-bit CSR subregisters and 64-bit CPUs. NOTE: this is a non-functional change. Signed-off-by: Gabriel Somlo <gsomlo@gmail.com> Signed-off-by: Stafford Horne <shorne@gmail.com>
Diffstat (limited to 'drivers')
-rw-r--r--drivers/soc/litex/litex_soc_ctrl.c73
1 files changed, 0 insertions, 73 deletions
diff --git a/drivers/soc/litex/litex_soc_ctrl.c b/drivers/soc/litex/litex_soc_ctrl.c
index 1217cafdfd4d..65977526d68e 100644
--- a/drivers/soc/litex/litex_soc_ctrl.c
+++ b/drivers/soc/litex/litex_soc_ctrl.c
@@ -16,79 +16,6 @@
#include <linux/errno.h>
#include <linux/io.h>
-/*
- * LiteX SoC Generator, depending on the configuration, can split a single
- * logical CSR (Control&Status Register) into a series of consecutive physical
- * registers.
- *
- * For example, in the configuration with 8-bit CSR Bus, 32-bit aligned (the
- * default one for 32-bit CPUs) a 32-bit logical CSR will be generated as four
- * 32-bit physical registers, each one containing one byte of meaningful data.
- *
- * For details see: https://github.com/enjoy-digital/litex/wiki/CSR-Bus
- *
- * The purpose of `litex_set_reg`/`litex_get_reg` is to implement the logic
- * of writing to/reading from the LiteX CSR in a single place that can be
- * then reused by all LiteX drivers.
- */
-
-/**
- * litex_set_reg() - Writes the value to the LiteX CSR (Control&Status Register)
- * @reg: Address of the CSR
- * @reg_size: The width of the CSR expressed in the number of bytes
- * @val: Value to be written to the CSR
- *
- * In the currently supported LiteX configuration (8-bit CSR Bus, 32-bit aligned),
- * a 32-bit LiteX CSR is generated as 4 consecutive 32-bit physical registers,
- * each one containing one byte of meaningful data.
- *
- * This function splits a single possibly multi-byte write into a series of
- * single-byte writes with a proper offset.
- */
-void litex_set_reg(void __iomem *reg, unsigned long reg_size,
- unsigned long val)
-{
- unsigned long shifted_data, shift, i;
-
- for (i = 0; i < reg_size; ++i) {
- shift = ((reg_size - i - 1) * LITEX_SUBREG_SIZE_BIT);
- shifted_data = val >> shift;
-
- WRITE_LITEX_SUBREGISTER(shifted_data, reg, i);
- }
-}
-EXPORT_SYMBOL_GPL(litex_set_reg);
-
-/**
- * litex_get_reg() - Reads the value of the LiteX CSR (Control&Status Register)
- * @reg: Address of the CSR
- * @reg_size: The width of the CSR expressed in the number of bytes
- *
- * Return: Value read from the CSR
- *
- * In the currently supported LiteX configuration (8-bit CSR Bus, 32-bit aligned),
- * a 32-bit LiteX CSR is generated as 4 consecutive 32-bit physical registers,
- * each one containing one byte of meaningful data.
- *
- * This function generates a series of single-byte reads with a proper offset
- * and joins their results into a single multi-byte value.
- */
-unsigned long litex_get_reg(void __iomem *reg, unsigned long reg_size)
-{
- unsigned long shifted_data, shift, i;
- unsigned long result = 0;
-
- for (i = 0; i < reg_size; ++i) {
- shifted_data = READ_LITEX_SUBREGISTER(reg, i);
-
- shift = ((reg_size - i - 1) * LITEX_SUBREG_SIZE_BIT);
- result |= (shifted_data << shift);
- }
-
- return result;
-}
-EXPORT_SYMBOL_GPL(litex_get_reg);
-
#define SCRATCH_REG_OFF 0x04
#define SCRATCH_REG_VALUE 0x12345678
#define SCRATCH_TEST_VALUE 0xdeadbeef